412-00 Climate Control System - General Information 2014 Fiesta
Diagnosis and Testing Procedure revision date: 05/16/2013

Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC)

DTC Chart: Powertrain Control Module (PCM)

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices. For information about these practices,
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).

Network Diagnostic Trouble Codes (DTCs) (U-codes) are often a result of intermittent concerns such as damaged wiring or low battery voltage occurrences. Additionally, vehicle repair procedures, such as module reprogramming, often set network Diagnostic Trouble Codes (DTCs). Replacing a module to resolve a network DTC is unlikely to resolve the concern. To prevent repeat network DTC concerns, inspect all network wiring, especially connectors. Test the vehicle battery.
REFER to: Battery (414-01 Battery, Mounting and Cables, Diagnosis and Testing).




DTC Description Action
All Other PCM Diagnostic Trouble Codes (DTCs) not listed in this chart —
  • For 1.6L EcoBoost,
    REFER to: Electronic Engine Controls (303-14B Electronic Engine Controls - 1.6L EcoBoost (132kW/180PS) - Sigma, Diagnosis and Testing).
  • For 1.6L Duratec-16V Ti-VCT,
    REFER to: Electronic Engine Controls (303-14A Electronic Engine Controls - 1.6L Duratec-16V Ti-VCT (88kW/120PS) - Sigma, Diagnosis and Testing).
P0532 A/C Refrigerant Pressure Sensor "A" Circuit Low
P0533 A/C Refrigerant Pressure Sensor "A" Circuit High
P0645 A/C Clutch Relay Control Circuit
P0646 A/C Clutch Relay Control Circuit Low
P0647 A/C Clutch Relay Control Circuit High


DTC Chart: Instrument Panel Cluster (IPC)

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices. For information about these practices,
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).




Condition Possible Sources Actions
All Other IPC Diagnostic Trouble Codes (DTCs) not listed in this chart —  
REFER to: Instrumentation, Message Center and Warning Chimes (413-01 Instrumentation, Message Center and Warning Chimes, Diagnosis and Testing).
B1B71:11 Evaporator Temperature Sensor: Circuit Short To Ground   GO to Pinpoint Test N
B1B71:13 Evaporator Temperature Sensor: Circuit Open   GO to Pinpoint Test N


DTC Chart: Heating Ventilation Air Conditioning (HVAC) Control Module - Electronic Automatic Temperature Control (EATC)

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices. For information about these practices,
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).

Network Diagnostic Trouble Codes (DTCs) (U-codes) are often a result of intermittent concerns such as damaged wiring or low battery voltage occurrences. Additionally, vehicle repair procedures, such as module reprogramming, often set network Diagnostic Trouble Codes (DTCs). Replacing a module to resolve a network DTC is unlikely to resolve the concern. To prevent repeat network DTC concerns, inspect all network wiring, especially connectors. Test the vehicle battery.
REFER to: Battery (414-01 Battery, Mounting and Cables, Diagnosis and Testing).




DTC Description Action
B105A:11 Cabin Temperature Sensor Fan: Circuit Short To Ground   GO to Pinpoint Test O
B105A:15 Cabin Temperature Sensor Fan: Circuit Short To Battery or Open   GO to Pinpoint Test O
B1081:11 Left Temperature Damper Motor: Circuit Short To Ground   GO to Pinpoint Test K
B1081:12 Left Temperature Damper Motor: Circuit Short To Battery   GO to Pinpoint Test K
B1083:11 Recirculation Damper Motor: Circuit Short To Ground   GO to Pinpoint Test F
B1083:12 Recirculation Damper Motor: Circuit Short To Battery   GO to Pinpoint Test F
B1086:11 Air Distribution Damper Motor: Circuit Short To Ground   GO to Pinpoint Test R
B1086:12 Air Distribution Damper Motor: Circuit Short To Battery   GO to Pinpoint Test R
B10B5:11 Left Panel Air Discharge Temperature: Circuit Short To Ground   GO to Pinpoint Test Q
B10B5:15 Left Panel Air Discharge Temperature: Circuit Short To Battery or Open   GO to Pinpoint Test Q
B10B6:11 Left Floor Air Discharge Temperature: Circuit Short To Ground   GO to Pinpoint Test R
B10B6:15 Left Floor Air Discharge Temperature: Circuit Short To Battery or Open   GO to Pinpoint Test R
B10B8:97 Push Buttons: Component or System Operation Obstructed or Blocked Buttons held too long may set this DTC . ATTEMPT to clean buttons. CLEAR the Diagnostic Trouble Codes (DTCs) and REPEAT the self-test. If the DTC does not return, IGNORE the DTC and CONTINUE diagnosing other Diagnostic Trouble Codes (DTCs) or symptoms. If the DTC returns, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
B10B9:12 Blower Control: Circuit Short To Battery   GO to Pinpoint Test L
B10B9:14 Blower Control: Circuit Short To Ground or Open   GO to Pinpoint Test L
B1A59:11 Sensor 5 Volt Supply: Circuit Short To Ground   GO to Pinpoint Test S
B1A59:12 Sensor 5 Volt Supply: Circuit Short To Battery   GO to Pinpoint Test S
B1A61:11 Cabin Temperature Sensor: Circuit Short To Ground   GO to Pinpoint Test O
B1A61:15 Cabin Temperature Sensor: Circuit Short To Battery or Open   GO to Pinpoint Test O
B1A63:11 Right Solar Sensor: Circuit Short To Ground   GO to Pinpoint Test P
B1A63:15 Right Solar Sensor: Circuit Short To Battery or Open   GO to Pinpoint Test P
B1A64:11 Left Solar Sensor: Circuit Short To Ground   GO to Pinpoint Test P
B1A64:15 Left Solar Sensor: Circuit Short To Battery or Open   GO to Pinpoint Test P
U0140:00 Lost Communication With Body Control Module: No Sub Type Information   GO to Pinpoint Test T
U0155:00 Lost Communication With Instrument Panel Cluster (IPC) Control Module: No Sub Type Information   GO to Pinpoint Test U
U2100:00 Initial Configuration Not Complete: No Sub Type Information CARRY OUT PMI on the HVAC control module.
REFER to: Module Configuration - System Operation and Component Description (418-01 Module Configuration, Description and Operation).
REPEAT the self-test. If PMI is successful, the DTC will not be present. If the DTC returns, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
U2101:00 Control Module Configuration Incompatible: No Sub Type Information CHECK vehicle service history for recent service actions related to this module. This DTC sets due to incomplete or incorrect PMI procedures. If there have been recent service actions with this module, REPEAT or PERFORM the PMI procedure as directed by the scan tool.
REFER to: Module Configuration - System Operation and Component Description (418-01 Module Configuration, Description and Operation).
If there have been no recent service actions, INSTALL a new HVAC control module to correct the failure to retain configuration data.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
U3000:00 Control Module: No Sub Type Information INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
U3006:16 Control Module Input Power "A":Circuit Voltage Below Threshold   GO to Pinpoint Test V
U3006:17 Control Module Input Power "A":Circuit Voltage Above Threshold   GO to Pinpoint Test V


Symptom Chart(s)

Symptom Chart:

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices. For information about these practices,
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).




Condition Possible Sources Actions
Unable to duplicate the customer concern and no Diagnostic Trouble Codes (DTCs) present Refer to Pinpoint Test   GO to Pinpoint Test E
Reduced outlet airflow Refer to Pinpoint Test
The air inlet door is inoperative Refer to Pinpoint Test   GO to Pinpoint Test F
Incorrect or erratic direction of airflow from outlets Refer to Pinpoint Test   GO to Pinpoint Test G
Insufficient, erratic or no heat Refer to Pinpoint Test   GO to Pinpoint Test H
The A/C is inoperative Refer to Pinpoint Test   GO to Pinpoint Test I
Insufficient A/C cooling Improper refrigerant level
Temperature door actuator   GO to Pinpoint Test K
The A/C is always on — A/C mode always commanded ON Refer to Pinpoint Test   GO to Pinpoint Test J
Temperature control is inoperative or does not operate correctly Refer to Pinpoint Test   GO to Pinpoint Test K
The blower motor is inoperative Refer to Pinpoint Test   GO to Pinpoint Test L
The blower motor does not operate correctly Refer to Pinpoint Test   GO to Pinpoint Test M
A/C pressure relief valve discharging High system pressure
A/C pressure relief valve


Symptom Chart: Noise, Vibration, and Harshness (NVH)

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices. For information about these practices,
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).




Condition Possible Sources Actions
Noisy A/C compressor A/C compressor bearing worn
Excessive hissing from the plenum when the A/C is on Low refrigerant charge


Pinpoint Test(s)

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices. For information about these practices,
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).

P0532, P0533 FOR 1.6L EcoBoost


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

The A/C pressure transducer receives a ground from the PCM . A 5-volt reference voltage is supplied to the A/C pressure transducer from the PCM . The A/C pressure transducer then sends a voltage to the PCM to indicate the A/C pressure.



  Diagnostic Trouble Code (DTC) Fault Trigger Conditions


DTC Description Fault Trigger Conditions
P0532 A/C Refrigerant Pressure Sensor "A" Circuit Low The A/C pressure transducer inputs a feedback voltage to the PCM . This DTC sets if the feedback voltage is less than 0.620 volt for at least 1 second and the ambient air temperature is greater than 0°C (32°F).
P0533 A/C Refrigerant Pressure Sensor "A" Circuit High The A/C pressure transducer inputs a feedback voltage to the PCM . This DTC sets if the feedback voltage is greater than 4.90 volts for at least 1 second and the ambient air temperature is greater than 0°C (32°F).


Possible Sources

Visual Inspection and Diagnostic Pre-checks


PINPOINT TEST A : P0532, P0533 FOR 1.6L ECOBOOST
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
A1   COMPARE THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) PRESSURE SENSOR (ACP_PRESS) PID (PARAMETER IDENTIFICATION) WITH THE MANIFOLD GAUGE SET READINGS
  • Allow the A/C system to stabilize to the outside ambient temperature.
  • Ignition ON.
  • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
  • With the manifold gauge set connected, compare the pressure readings of the manifold gauge set and the PCM ACP_PRESS PID .

Are the pressure values of the manifold gauge set and the PCM ACP_PRESS PID within +/-15 psi (103.4 kPa)?

Yes IGNORE the Diagnostic Trouble Codes (DTCs). REFER to the Symptom Chart in this section.
No GO to A2


A2   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER VREF CIRCUIT
  • Ignition OFF.
  • Disconnect A/C Pressure Transducer C1260 .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-3   Ground



Is the voltage between 4.7 and 5.1 volts?

Yes GO to A5
No If the voltage is less than 4.7 volts, GO to A3
If the voltage is greater than 5.1 volts, REPAIR the circuit for a short to voltage.


A3   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER VREF CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect PCM C1915B .
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-3   Ground



Is the resistance greater than 10,000 ohms?

Yes GO to A4
No REPAIR the circuit.


A4   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER VREF CIRCUIT FOR AN OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-3   C1915B-14



Is the resistance less than 3 ohms?

Yes GO to A14
No REPAIR the circuit.


A5   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER SIGNAL RETURN CIRCUIT
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-1   C1260-3



Is the voltage greater than 4.7 volts?

Yes If diagnosing DTC P0532, GO to A8
If diagnosing DTC P0533, GO to A11
No GO to A6


A6   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER SIGNAL RETURN CIRCUIT FOR VOLTAGE
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-1   Ground



Is any voltage present?

Yes If the voltage is less than 5.1 volts, REPAIR the signal return circuit for a short to the vref circuit. If the voltage is greater than 5.1 volts, REPAIR the signal return circuit for a short to voltage.
No GO to A7


A7   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER SIGNAL RETURN CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect PCM C1915B .
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-1   C1915B-17



Is the resistance less than 3 ohms?

Yes GO to A14
No REPAIR the circuit.


A8   CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) PRESSURE SENSOR VOLTAGE (ACP_V) PID (PARAMETER IDENTIFICATION) WITH THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER SHORTED
  • Connect a fused jumper wire between:


    Positive Lead Measurement / Action Negative Lead
      C1260-2   C1260-3


  • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
  • Monitor the PCM ACP_V PID .

Does the PID voltage display between 4.7 and 5.1 volts?

Yes INSTALL a new A/C pressure transducer.
REFER to: Air Conditioning (A/C) Pressure Transducer - 1.6L EcoBoost (132kW/180PS) - Sigma (412-00 Climate Control System - General Information, Removal and Installation).
No REMOVE the fused jumper wire. GO to A9


A9   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR A SHORT TO THE SIGNAL RETURN CIRCUIT
  • Ignition OFF.
  • Disconnect PCM C1915B .
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-2   C1260-1



Is the resistance greater than 10,000 ohms?

Yes GO to A10
No REPAIR the circuits.


A10   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR AN OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-2   C1915B-52



Is the resistance less than 3 ohms?

Yes GO to A14
No REPAIR the circuit.


A11   CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) PRESSURE SENSOR VOLTAGE (ACP_V) PID (PARAMETER IDENTIFICATION)
  • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
  • Monitor the PCM ACP_V PID .

Does the PID voltage display 0 volts?

Yes INSTALL a new A/C pressure transducer.
REFER to: Air Conditioning (A/C) Pressure Transducer - 1.6L EcoBoost (132kW/180PS) - Sigma (412-00 Climate Control System - General Information, Removal and Installation).
No GO to A12


A12   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR VOLTAGE
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-2   Ground



Is any voltage present?

Yes GO to A13
No GO to A14


A13   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect PCM C1915B .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-2   Ground



Is any voltage present?

Yes REPAIR the circuit.
No REPAIR the vref circuit for a short to the feedback circuit.


A14   CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION
  • Ignition OFF.
  • Disconnect and inspect all PCM connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the PCM connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new PCM .
REFER to: Powertrain Control Module (PCM) (303-14B Electronic Engine Controls - 1.6L EcoBoost (132kW/180PS) - Sigma, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



P0532, P0533 For 1.6L Duratec-16V Ti-VCT


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

The A/C pressure transducer receives a ground from the PCM . A 5-volt reference voltage is supplied to the A/C pressure transducer from the PCM . The A/C pressure transducer then sends a voltage to the PCM to indicate the A/C pressure.



  Diagnostic Trouble Code (DTC) Fault Trigger Conditions


DTC Description Fault Trigger Conditions
P0532 A/C Refrigerant Pressure Sensor "A" Circuit Low The A/C pressure transducer inputs a feedback voltage to the PCM . This DTC sets if the feedback voltage is less than 0.620 volt for at least 1 second and the ambient air temperature is greater than 0°C (32°F).
P0533 A/C Refrigerant Pressure Sensor "A" Circuit High The A/C pressure transducer inputs a feedback voltage to the PCM . This DTC sets if the feedback voltage is greater than 4.90 volts for at least 1 second and the ambient air temperature is greater than 0°C (32°F).


Possible Sources

Visual Inspection and Diagnostic Pre-checks


PINPOINT TEST B : P0532, P0533 FOR 1.6L DURATEC-16V TI-VCT
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
B1   COMPARE THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) PRESSURE SENSOR (ACP_PRESS) PID (PARAMETER IDENTIFICATION) WITH THE MANIFOLD GAUGE SET READINGS
  • Allow the A/C system to stabilize to the outside ambient temperature.
  • Ignition ON.
  • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
  • With the manifold gauge set connected, compare the pressure readings of the manifold gauge set and the PCM ACP_PRESS PID .

Are the pressure values of the manifold gauge set and the PID within +/-15 psi (103.4 kPa)?

Yes IGNORE the Diagnostic Trouble Codes (DTCs). REFER to the Symptom Chart in this section.
No GO to B2


B2   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER VREF CIRCUIT
  • Ignition OFF.
  • Disconnect A/C Pressure Transducer C1260 .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-3   Ground



Is the voltage between 4.7 and 5.1 volts?

Yes GO to B5
No If the voltage is less than 4.7 volts, GO to B3
If the voltage is greater than 5.1 volts, REPAIR the circuit for a short to voltage.


B3   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER VREF CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect PCM C175B .
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-3   Ground



Is the resistance greater than 10,000 ohms?

Yes GO to B4
No REPAIR the circuit.


B4   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER VREF CIRCUIT FOR AN OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-3   C175B-16



Is the resistance less than 3 ohms?

Yes GO to B14
No REPAIR the circuit.


B5   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER SIGNAL RETURN CIRCUIT
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-1   C1260-3



Is the voltage greater than 4.7 volts?

Yes If diagnosing DTC P0532, GO to B8
If diagnosing DTC P0533, GO to B11
No GO to B6


B6   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER SIGNAL RETURN CIRCUIT FOR VOLTAGE
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-1   Ground



Is any voltage present?

Yes If the voltage is less than 5.1 volts, REPAIR the signal return circuit for a short to the vref circuit. If the voltage is greater than 5.1 volts, REPAIR the signal return circuit for a short to voltage.
No GO to B7


B7   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER SIGNAL RETURN CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect PCM C175B .
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-1   C175B-40



Is the resistance less than 3 ohms?

Yes GO to B14
No REPAIR the circuit.


B8   CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) PRESSURE SENSOR VOLTAGE (ACP_V) PID (PARAMETER IDENTIFICATION) WITH THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER SHORTED
  • Connect a fused jumper wire between:


    Positive Lead Measurement / Action Negative Lead
      C1260-2   C1260-3


  • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
  • Monitor the PCM ACP_V PID .

Does the PID voltage read between 4.7 and 5.1 volts?

Yes INSTALL a new A/C pressure transducer.
REFER to: Air Conditioning (A/C) Pressure Transducer - 1.6L Duratec-16V Ti-VCT (88kW/120PS) - Sigma (412-00 Climate Control System - General Information, Removal and Installation).
No REMOVE the fused jumper wire. GO to B9


B9   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR A SHORT TO THE SIGNAL RETURN CIRCUIT
  • Ignition OFF.
  • Disconnect PCM C175B .
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-2   C1260-1



Is the resistance greater than 10,000 ohms?

Yes GO to B10
No REPAIR the circuits.


B10   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR AN OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-2   C175B-28



Is the resistance less than 3 ohms?

Yes GO to B14
No REPAIR the circuit.


B11   CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) PRESSURE SENSOR VOLTAGE (ACP_V) PID (PARAMETER IDENTIFICATION)
  • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
  • Monitor the PCM ACP_V PID .

Does the PID voltage display 0 volts?

Yes INSTALL a new A/C pressure transducer.
REFER to: Air Conditioning (A/C) Pressure Transducer - 1.6L Duratec-16V Ti-VCT (88kW/120PS) - Sigma (412-00 Climate Control System - General Information, Removal and Installation).
No GO to B12


B12   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR VOLTAGE
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-2   Ground



Is any voltage present?

Yes GO to B13
No GO to B14


B13   CHECK THE A/C (AIR CONDITIONING) PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect PCM C175B .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C1260-2   Ground



Is any voltage present?

Yes REPAIR the circuit.
No REPAIR the vref circuit for a short to the feedback circuit.


B14   CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION
  • Ignition OFF.
  • Disconnect and inspect all PCM connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the PCM connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new PCM .
REFER to: Powertrain Control Module (PCM) (303-14A Electronic Engine Controls - 1.6L Duratec-16V Ti-VCT (88kW/120PS) - Sigma, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



P0645, P0646, P0647 For 1.6L EcoBoost


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

Voltage is provided to the A/C clutch relay coil. When A/C is requested and A/C line pressures allow, a ground is provided to the A/C clutch relay coil from the PCM , energizing the A/C clutch relay.



  Diagnostic Trouble Code (DTC) Fault Trigger Conditions


DTC Description Fault Trigger Conditions
P0645 A/C Clutch Relay Control Circuit This DTC sets when the PCM grounds the relay circuit and more voltage than expected is detected on the relay circuit. This DTC also sets when the relay circuit is OFF and no voltage is detected on the relay circuit. The PCM expects to detect voltage coming through the relay coil to the relay circuit when it is not grounding it.
P0646 A/C Clutch Relay Control Circuit Low This DTC sets when the relay circuit is OFF and ground is detected on the relay circuit.
P0647 A/C Clutch Relay Control Circuit High This DTC sets when the PCM grounds the relay circuit and excessive current draw (short to voltage) is detected on the relay circuit while A/C is ON.


Possible Sources

Visual Inspection and Diagnostic Pre-checks


PINPOINT TEST C : P0645, P0646, P0647 FOR 1.6L ECOBOOST
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
C1   CHECK THE VOLTAGE TO THE A/C (AIR CONDITIONING) CLUTCH RELAY COIL
  • Ignition OFF.
  • Disconnect A/C Clutch Relay.
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 1     		  Ground



Is the voltage greater than 11 volts?

Yes GO to C2
No VERIFY BJB fuse 24 (10A) is OK. If OK, REPAIR circuit for an open. If not OK, REFER to the Wiring Diagrams manual to identify the possible causes of the circuit short.


C2   CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY
  • Carry out the Relay - Micro ISO component test on the A/C clutch relay.
    Refer to Wiring Diagrams Cell 149 for schematic and connector information.

Did the relay pass the component test?

Yes GO to C3
No INSTALL a new A/C clutch relay.


C3   CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY COIL CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect PCM C1915B .
  • Ignition ON.
  • Measure


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 2     		  Ground



Is any voltage present?

Yes REPAIR the circuit.
No GO to C4


C4   CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY COIL CONTROL CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Measure


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 2     		  Ground



Is the resistance greater than 10,000 ohms?

Yes GO to C5
No REPAIR the circuit.


C5   CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY COIL CONTROL CIRCUIT FOR AN OPEN
  • Measure


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 2     		  C1915B-2



Is the resistance less than 3 ohms?

Yes GO to C6
No REPAIR the circuit.


C6   CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION
  • Ignition OFF.
  • Disconnect and inspect all PCM connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the PCM connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new PCM .
REFER to: Powertrain Control Module (PCM) (303-14B Electronic Engine Controls - 1.6L EcoBoost (132kW/180PS) - Sigma, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



P0645, P0646, P0647 For 1.6L Duratec-16V Ti-VCT


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

Voltage is provided to the A/C clutch relay coil. When A/C is requested and A/C line pressures allow, a ground is provided to the A/C clutch relay coil from the PCM , energizing the A/C clutch relay.



  Diagnostic Trouble Code (DTC) Fault Trigger Conditions


DTC Description Fault Trigger Conditions
P0645 A/C Clutch Relay Control Circuit This DTC sets when the PCM grounds the relay circuit and more voltage than expected is detected on the relay circuit. This DTC also sets when the relay circuit is OFF and no voltage is detected on the relay circuit. The PCM expects to detect voltage coming through the relay coil to the relay circuit when it is not grounding it.
P0646 A/C Clutch Relay Control Circuit Low This DTC sets when the relay circuit is OFF and ground is detected on the relay circuit.
P0647 A/C Clutch Relay Control Circuit High This DTC sets when the PCM grounds the relay circuit and excessive current draw (short to voltage) is detected on the relay circuit while A/C is ON.


Possible Sources

Visual Inspection and Diagnostic Pre-checks


PINPOINT TEST D : P0645, P0646, P0647 FOR 1.6L DURATEC-16V TI-VCT
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
D1   CHECK THE VOLTAGE TO THE A/C (AIR CONDITIONING) CLUTCH RELAY COIL
  • Ignition OFF.
  • Disconnect A/C Clutch Relay.
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 1     		  Ground



Is the voltage greater than 11 volts?

Yes GO to D2
No VERIFY BJB fuse 24 (10A) is OK. If OK, REPAIR circuit for an open. If not OK, REFER to the Wiring Diagrams manual to identify the possible causes of the circuit short.


D2   CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY
  • Carry out the Relay - Micro ISO component test on the A/C clutch relay.
    Refer to Wiring Diagrams Cell 149 for schematic and connector information.

Did the relay pass the component test?

Yes GO to D3
No INSTALL a new A/C clutch relay.


D3   CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY COIL CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect PCM C175B .
  • Ignition ON.
  • Measure


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 2     		  Ground



Is any voltage present?

Yes REPAIR the circuit.
No GO to D4


D4   CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY COIL CONTROL CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Measure


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 2     		  Ground



Is the resistance greater than 10,000 ohms?

Yes GO to D5
No REPAIR the circuit.


D5   CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY COIL CONTROL CIRCUIT FOR AN OPEN
  • Measure


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 2     		  C175B-25



Is the resistance less than 3 ohms?

Yes GO to D6
No REPAIR the circuit.


D6   CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION
  • Ignition OFF.
  • Disconnect and inspect all PCM connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the PCM connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new PCM .
REFER to: Powertrain Control Module (PCM) (303-14A Electronic Engine Controls - 1.6L Duratec-16V Ti-VCT (88kW/120PS) - Sigma, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



Unable To Duplicate The Customer Concern And No Diagnostic Trouble Codes (DTCs) Present

This pinpoint test tests the functions of the HVAC system and identifies the correct HVAC symptom pinpoint test.


PINPOINT TEST E : UNABLE TO DUPLICATE THE CUSTOMER CONCERN AND NO DIAGNOSTIC TROUBLE CODES (DTCS) PRESENT
E1   CHECK THE BLOWER MOTOR OPERATION
  • Ignition ON.
  • Select PANEL mode.
  • Observe blower motor operation and select each blower motor speed.

Does the blower motor operate in all selections and change speed in each?

Yes GO to E2
No If the blower motor does not operate in any setting, GO to Pinpoint Test L
If the blower motor does not properly change speeds or shut off, GO to Pinpoint Test M


E2   CHECK AIRFLOW OPERATION
  • Select the highest blower motor setting.
  • While observing the airflow, select each of the airflow positions (PANEL, PANEL/FLOOR, FLOOR, FLOOR/DEFROST, DEFROST).

Is the airflow directed to the correct outlets?

Yes GO to E3
No GO to Pinpoint Test G


E3   VERIFY TEMPERATURE CONTROL OPERATION
  • Start the vehicle and allow it to reach normal operating temperature.
  • With the A/C off, select PANEL mode.
  • Change the temperature setting from the coldest to the warmest and back to the coldest.

Does the temperature change between very warm to cool?

Yes GO to E4
No If the temperature does not get very warm, GO to Pinpoint Test H
If the temperature does not change at all, GO to Pinpoint Test K


E4   VERIFY THE A/C (AIR CONDITIONING) CLUTCH DOES NOT ENGAGE WITH A/C (AIR CONDITIONING) OFF
  • With the engine running and the A/C off, select PANEL mode.
  • Select the coldest temperature setting.

Is the outlet temperature close to ambient temperature?

Yes GO to E5
No If the temperature is warmer than ambient temperature, GO to Pinpoint Test I
If the outlet temperature is significantly colder than ambient temperature and the A/C compressor clutch engages, GO to Pinpoint Test J


E5   VERIFY A/C (AIR CONDITIONING) CLUTCH ENGAGEMENT IN THE A/C (AIR CONDITIONING) MODE
  • Make sure the ambient air temperature is above 2°C (36°F).
  • With the engine running, select PANEL mode.
  • Press the A/C button (indicator on).

Does the A/C clutch engage when in PANEL mode and the A/C button (indicator on) is pressed?

Yes GO to E6
No GO to Pinpoint Test I


E6   CHECK THE RECIRC OPERATION
  • With the engine running, press the RECIRC button (indicator off).
  • Select PANEL mode.
  • Select the highest blower motor setting.
  • Observe airflow noise.
  • Press the RECIRC button (indicator on).

Does the airflow noise increase when the RECIRC mode is selected (indicator on)?

Yes The system is operating normally.
No GO to Pinpoint Test F



The Air Inlet Door Is Inoperative


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

Air Inlet Door Actuator,
REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description (412-00 Climate Control System - General Information, Description and Operation).



  Diagnostic Trouble Code (DTC) Fault Trigger Conditions


DTC Description Fault Trigger Conditions
B1083:11 Recirculation Damper Motor: Circuit Short To Ground The HVAC control module senses lower than expected voltage on the motor circuits, indicating a short to ground.
B1083:12 Recirculation Damper Motor: Circuit Short To Battery The HVAC control module senses greater than expected voltage on the motor circuits, indicating a short to voltage.


Possible Sources

Visual Inspection and Diagnostic Pre-checks


PINPOINT TEST F : THE AIR INLET DOOR IS INOPERATIVE
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
F1   CHECK THE AIR INLET DOOR ACTUATOR MOTOR CIRCUITS FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect Air Inlet Door Actuator C2091 .
  • Disconnect HVAC control module C228A .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2091-1   Ground
      C2091-6   Ground



Is any voltage present?

Yes REPAIR the affected circuits.
No GO to F2


F2   CHECK THE AIR INLET DOOR ACTUATOR MOTOR CIRCUITS FOR A SHORT TO GROUND
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2091-1   Ground
      C2091-6   Ground



Are the resistances greater than 10,000 ohms?

Yes GO to F3
No REPAIR the affected circuits.


F3   CHECK THE AIR INLET DOOR ACTUATOR MOTOR CIRCUITS FOR AN OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2091-1   C228A-7
      C2091-6   C228A-8



Are the resistances less than 3 ohms?

Yes GO to F4
No REPAIR the affected circuits.


F4   CHECK THE AIR INLET DOOR ACTUATOR MOTOR CIRCUITS FOR A SHORT TOGETHER
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2091-1   C2091-6



Is the resistance greater than 10,000 ohms?

Yes INSTALL a new air inlet door actuator.
REFER to: Air Inlet Door Actuator (412-00 Climate Control System - General Information, Removal and Installation).
TEST the system for normal operation. If the concern is still present, GO to F5
No REPAIR the circuits.


F5   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



Incorrect Or Erratic Direction Of Airflow From Outlets


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

Air distribution door actuator,
REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description (412-00 Climate Control System - General Information, Description and Operation).



  Diagnostic Trouble Code (DTC) Fault Trigger Conditions


DTC Description Fault Trigger Conditions
B1086:11 Air Distribution Damper Motor: Circuit Short To Ground The HVAC control module senses lower than expected voltage on the motor circuits, indicating a short to ground.
B1086:12 Air Distribution Damper Motor: Circuit Short To Battery The HVAC control module senses greater than expected voltage on the motor circuits, indicating a short to voltage.


Possible Sources

Visual Inspection and Diagnostic Pre-checks


PINPOINT TEST G : INCORRECT OR ERRATIC DIRECTION OF AIRFLOW FROM OUTLETS
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
G1   CHECK THE AIR DISTRIBUTION DOOR ACTUATOR CIRCUITS FOR A SHORT TO VOLTAGE
  • Disconnect HVAC control module C228A .
  • Disconnect Air Distribution Door Actuator C236 .
  • Disconnect Temperature Door Actuator C2092 .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C236-1   Ground
      C236-2   Ground
      C236-3   Ground
      C236-4   Ground
      C236-6   Ground



Is there any voltage present?

Yes REPAIR the circuit in question.
No GO to G2


G2   CHECK THE AIR DISTRIBUTION DOOR ACTUATOR CIRCUITS FOR A SHORT TO GROUND
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C236-1   Ground
      C236-2   Ground
      C236-3   Ground
      C236-4   Ground
      C236-6   Ground



Are the resistances greater than 10,000 ohms?

Yes GO to G3
No REPAIR the circuit in question.


G3   CHECK THE AIR DISTRIBUTION DOOR ACTUATOR CIRCUITS FOR AN OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C236-1   C228A-9
      C236-2   C228A-12
      C236-3   C228A-13
      C236-4   C228A-15
      C236-6   C228A-4



Are the resistances less than 3 ohms?

Yes INSTALL a new air distribution door actuator.
REFER to: Air Distribution Door Actuator (412-00 Climate Control System - General Information, Removal and Installation).
Operate the system and determine if the concern is still present. If the concern is still present, GO to G4
No REPAIR the circuit in question.


G4   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



Insufficient, Erratic Or No Heat


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

When the engine is at operating temperature hot coolant flows from the engine through the heater core and back to the engine. Correct coolant temperatures are critical for good heater performance.

Possible Sources

Visual Inspection and Diagnostic Pre-checks


PINPOINT TEST H : INSUFFICIENT, ERRATIC OR NO HEAT
H1   CHECK FOR CORRECT ENGINE COOLANT LEVEL
  • Ignition OFF.
  • Check the engine coolant level.

Is the engine coolant at the correct level (hot/cold) as indicated on the engine coolant recovery reservoir?

Yes GO to H2
No For 1.6L EcoBoost,
REFER to: Engine Cooling (303-03B Engine Cooling - 1.6L EcoBoost (132kW/180PS) - Sigma, Diagnosis and Testing).

For 1.6L Duratec-16V Ti-VCT,
REFER to: Engine Cooling (303-03A Engine Cooling - 1.6L Duratec-16V Ti-VCT (88kW/120PS) - Sigma, Diagnosis and Testing).


H2   CHECK FOR COOLANT FLOW TO THE HEATER CORE
  • Run the motor until it reaches normal operating temperature. Select the floor position on the control assembly. Set the temperature control to full warm and the blower to the lowest setting.
  • Using a suitable temperature measuring device, check the heater core inlet hose to see if it is hot.

Is the heater core inlet hose hot?

Yes GO to H3
No For 1.6L EcoBoost,
REFER to: Engine Cooling (303-03B Engine Cooling - 1.6L EcoBoost (132kW/180PS) - Sigma, Diagnosis and Testing).

For 1.6L Duratec-16V Ti-VCT,
REFER to: Engine Cooling (303-03A Engine Cooling - 1.6L Duratec-16V Ti-VCT (88kW/120PS) - Sigma, Diagnosis and Testing).


H3   CHECK FOR A PLUGGED OR RESTRICTED HEATER CORE
  • Using a suitable temperature measuring device, measure the heater core outlet hose temperature.

Is the heater core outlet hose temperature similar to the inlet hose temperature (within approximately 6-17°C [10-30°F])?

Yes DIAGNOSE for a temperature door actuator. GO to Pinpoint Test K
No INSTALL a new heater core.
REFER to: Heater Core (412-00 Climate Control System - General Information, Removal and Installation).



The A/C Is Inoperative


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

Control System Logic,
REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description (412-00 Climate Control System - General Information, Description and Operation).

Possible Sources

Visual Inspection and Diagnostic Pre-checks


PINPOINT TEST I : THE A/C (AIR CONDITIONING) IS INOPERATIVE
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
I1   CLEAR AND RETRIEVE DIAGNOSTIC TROUBLE CODES (DTCS)
  • Ignition ON.
  • Using a diagnostic scan tool, clear all Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • Wait 10 seconds.
  • Ignition ON.
  • Using a diagnostic scan tool, retrieve all Continuous Memory Diagnostic Trouble Codes (CMDTCs).

Are there any climate control related Diagnostic Trouble Codes (DTCs)?

Yes REFER to DTC charts in this section.
No GO to I2


I2   CHECK THE OUTSIDE AIR TEMPERATURE DISPLAY IN THE IPC (INSTRUMENT PANEL CLUSTER)
  • Ignition ON.
  • Observe the outside air temperature display in the IPC .

Is the outside air temperature display similar to the ambient temperature?

Yes GO to I3
No
REFER to: Instrumentation, Message Center and Warning Chimes (413-01 Instrumentation, Message Center and Warning Chimes, Diagnosis and Testing).


I3   CHECK THE A/C (AIR CONDITIONING) SYSTEM PRESSURE
  • Ignition OFF.
  • With the R-134a manifold gauge set connected, check the A/C system pressure.

Is the A/C system pressure above 290 kPa (42 psi)?

Yes GO to I4
No CHECK the A/C system for leaks.

REFER to: Electronic Leak Detection (412-00 Climate Control System - General Information, General Procedures).
or REFER to: Fluorescent Dye Leak Detection (412-00 Climate Control System - General Information, General Procedures).
RECHARGE the A/C system.
REFER to: Air Conditioning (A/C) System Recovery, Evacuation and Charging (412-00 Climate Control System - General Information, General Procedures).


I4   CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) PRESSURE SENSOR (ACP_PRESS) PID (PARAMETER IDENTIFICATION)
  • Ignition ON.
  • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
  • With the R-134a manifold gauge set connected, compare the pressure readings of the manifold gauge set and the PCM ACP_PRESS PID .

Are the pressure values of the manifold gauge set and the PCM ACP_PRESS PID similar?

Yes GO to I5
No INSTALL a new A/C pressure transducer.
For 1.6L EcoBoost,
REFER to: Air Conditioning (A/C) Pressure Transducer - 1.6L EcoBoost (132kW/180PS) - Sigma (412-00 Climate Control System - General Information, Removal and Installation).

For 1.6L Duratec-16V Ti-VCT,
REFER to: Air Conditioning (A/C) Pressure Transducer - 1.6L Duratec-16V Ti-VCT (88kW/120PS) - Sigma (412-00 Climate Control System - General Information, Removal and Installation).


I5   CHECK THE IPC (INSTRUMENT PANEL CLUSTER) A/C (AIR CONDITIONING) EVAPORATOR TEMPERATURE (EVAP_TEMP) PID (PARAMETER IDENTIFICATION)
  • Allow the vehicle exterior and interior to stabilize to the ambient temperature.
  • Ignition ON.
  • Using a diagnostic scan tool, view IPC Parameter Identifications (PIDs).
  • Monitor the IPC EVAP_TEMP PID .

Does the PID display similar to the ambient temperature?

Yes GO to I6
No GO to Pinpoint Test N


I6   CHECK THE HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE A/C (AIR CONDITIONING) SWITCH (A/C_SWITCH) PID (PARAMETER IDENTIFICATION) WITH THE A/C (AIR CONDITIONING) ON
  • Using a diagnostic scan tool, view HVAC Parameter Identifications (PIDs).
  • Monitor the HVAC control module A/C_SWITCH PID .
  • Select PANEL and press the A/C button (indicator on) on the HVAC controls.

Does the HVAC control module A/C_SWITCH PID display Active?

Yes GO to I7
No GO to I21


I7   CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) REQUEST SIGNAL (AC_REQ) PID (PARAMETER IDENTIFICATION) WITH THE A/C (AIR CONDITIONING) ON
  • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
  • Select PANEL and press the A/C button (indicator on) on the HVAC controls.
  • Monitor the PCM AC_REQ PID .

Does the PCM AC_REQ PID display Yes?

Yes GO to I8
No GO to I21


I8   CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) COMPRESSOR COMMANDED STATE (ACC_CMD) PID (PARAMETER IDENTIFICATION) WITH THE A/C (AIR CONDITIONING) ON
  • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
  • Select PANEL and press the A/C button (indicator on) on the HVAC controls.
  • Monitor the PCM ACC_CMD PID .

Does the PCM ACC_CMD PID display ON?

Yes GO to I9
No GO to I19


I9   CHECK THE VOLTAGE AT THE A/C (AIR CONDITIONING) COMPRESSOR CLUTCH FIELD COIL
  • Ignition OFF.
  • Disconnect A/C Compressor Clutch Field Coil C100 .
  • Start the engine.
  • Select MAX A/C on the HVAC controls.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C100-1   Ground



Is the voltage greater than 11 volts?

Yes GO to I10
No GO to I13


I10   CHECK THE GROUND AT THE A/C (AIR CONDITIONING) COMPRESSOR CLUTCH FIELD COIL
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C100-2   Ground



Is the resistance less than 3 ohms?

Yes GO to I11
No REPAIR the circuit.


I11   CHECK THE A/C (AIR CONDITIONING) COMPRESSOR CLUTCH FIELD COIL
  • Measure:


    Positive Lead Measurement / Action Negative Lead

    C100-1 (component side)

    C100-2 (component side)



Is the resistance between 2 and 5 ohms?

Yes GO to I12
No INSTALL a new A/C compressor clutch and field coil.
REFER to: Air Conditioning (A/C) Clutch and Air Conditioning (A/C) Clutch Field Coil (412-00 Climate Control System - General Information, Removal and Installation).


I12   CHECK THE A/C (AIR CONDITIONING) COMPRESSOR CLUTCH FIELD COIL FOR A SHORT TO GROUND
  • Measure:


    Positive Lead Measurement / Action Negative Lead

    C100-1 (component side)     		  Ground

    C100-2 (component side)     		  Ground



Are the resistances greater than 10,000 ohms?

Yes ADJUST the A/C compressor clutch gap.
REFER to: Air Conditioning (A/C) Clutch Air Gap Adjustment (412-00 Climate Control System - General Information, General Procedures).
No INSTALL a new A/C compressor clutch and field coil.
REFER to: Air Conditioning (A/C) Clutch and Air Conditioning (A/C) Clutch Field Coil (412-00 Climate Control System - General Information, Removal and Installation).


I13   CHECK THE VOLTAGE TO THE A/C (AIR CONDITIONING) CLUTCH RELAY COIL
  • Ignition OFF.
  • Disconnect A/C Clutch Relay.
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 1     		  Ground



Is the voltage greater than 11 volts?

Yes GO to I14
No VERIFY BJB fuse 24 (10A) is OK. If OK, REPAIR the circuit for an open. If not OK, REFER to the Wiring Diagrams manual to identify the possible causes of the circuit short.


I14   CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY

NOTICE: The following step uses a test light to simulate normal circuit loads. Use only a Rotunda Test Lamp (SGT27000) or 250-300mA incandescent bulb test lamp. To avoid connector terminal damage, use the Rotunda Flex Probe kit for the test lamp probe connection to the vehicle. Do not use the test lamp probe directly on any connector.

  • Start the engine.
  • Select PANEL and press the A/C button (indicator on) on the HVAC controls.
  • Connect a test light between:


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 1

    A/C clutch relay socket 2



Does the test light illuminate?

Yes GO to I17
No GO to I15


I15   CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY COIL CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect For 1.6L EcoBoost PCM C1915B .
  • Disconnect For 1.6L Duratec-16V Ti-VCT PCM C175B .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 2     		  Ground



Is any voltage present?

Yes REPAIR the circuit.
No GO to I16


I16   CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY COIL CONTROL CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • For 1.6L EcoBoost, measure:


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 2     		  C1915B-2


  • For 1.6L Duratec-16V Ti-VCT, measure:


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 2     		  C175B-25



Is the resistance less than 3 ohms?

Yes GO to I19
No REPAIR the circuit.


I17   CHECK THE VOLTAGE TO THE A/C (AIR CONDITIONING) CLUTCH RELAY SWITCH CONTACTS
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 3     		  Ground



Is the voltage greater than 11 volts?

Yes GO to I18
No VERIFY BJB fuse 30 (10A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the Wiring Diagrams manual to identify the possible causes of the circuit short.


I18   CHECK THE A/C (AIR CONDITIONING) COMPRESSOR CLUTCH FIELD COIL VOLTAGE CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead

    A/C clutch relay socket 5     		  C100-1



Is the resistance less than 3 ohms?

Yes INSTALL a new A/C clutch relay.
No REPAIR the circuit.


I19   CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION
  • Ignition OFF.
  • Disconnect and inspect all PCM connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the PCM connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new PCM .
For 1.6L EcoBoost
REFER to: Powertrain Control Module (PCM) (303-14B Electronic Engine Controls - 1.6L EcoBoost (132kW/180PS) - Sigma, Removal and Installation).

For 1.6L Duratec-16V Ti-VCT
REFER to: Powertrain Control Module (PCM) (303-14A Electronic Engine Controls - 1.6L Duratec-16V Ti-VCT (88kW/120PS) - Sigma, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.


I20   CHECK THE IPC (INSTRUMENT PANEL CLUSTER) OPERATION
  • Ignition OFF.
  • Disconnect and inspect the IPC connector.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the IPC connector. Make sure it seats and latches correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new IPC .
REFER to: Instrument Panel Cluster (IPC) (413-01 Instrumentation, Message Center and Warning Chimes, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.


I21   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



The A/C Is Always On – A/C Mode Always Commanded On


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

Control System Logic,
REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description (412-00 Climate Control System - General Information, Description and Operation).

Possible Sources


PINPOINT TEST J : THE A/C (AIR CONDITIONING) IS ALWAYS ON – A/C (AIR CONDITIONING) MODE ALWAYS COMMANDED ON
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
J1   PERFORM IPC (INSTRUMENT PANEL CLUSTER) SELF-TEST
  • Ignition ON.
  • Using a diagnostic scan tool, perform IPC self-test.

Are there any IPC Diagnostic Trouble Codes (DTCs) retrieved?

Yes REFER to the IPC DTC Chart in this section.
No GO to J2


J2   PERFORM PCM (POWERTRAIN CONTROL MODULE) SELF-TEST
  • Using a diagnostic scan tool, perform PCM self-test.

Are there any PCM Diagnostic Trouble Codes (DTCs) retrieved?

Yes REFER to the PCM DTC Chart in this section.
No GO to J3


J3   CHECK THE IPC (INSTRUMENT PANEL CLUSTER) A/C (AIR CONDITIONING) SWITCH (A/C_SWITCH) PID (PARAMETER IDENTIFICATION) WITH THE A/C (AIR CONDITIONING) OFF
  • Ignition ON.
  • Using a diagnostic scan tool, view IPC Parameter Identifications (PIDs).
  • Select PANEL and press the A/C button (indicator off) on the HVAC controls.
  • Monitor the IPC A/C_SWITCH PID .

Does the IPC A/C_SWITCH PID read INACTIVE?

Yes GO to J4
No GO to J6


J4   CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) REQUEST SIGNAL (AC_REQ) PID (PARAMETER IDENTIFICATION) WITH THE A/C (AIR CONDITIONING) OFF
  • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
  • Select PANEL and press the A/C button (indicator off) on the HVAC controls.
  • Monitor the PCM AC_REQ PID .

Does the PCM AC_REQ PID display NO?

Yes GO to J5
No GO to J7


J5   CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) COMPRESSOR COMMANDED STATE (ACC_CMD) PID (PARAMETER IDENTIFICATION) WITH THE A/C (AIR CONDITIONING) OFF
  • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
  • Select PANEL and press the A/C button (indicator off) on the HVAC controls.
  • Monitor the PCM ACC_CMD PID .

Does the PCM ACC_CMD PID display OFF?

Yes GO to J6
No GO to J7


J6   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.


J7   CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION
  • Ignition OFF.
  • Disconnect and inspect all PCM connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the PCM connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new PCM .
For 1.6L EcoBoost
REFER to: Powertrain Control Module (PCM) (303-14B Electronic Engine Controls - 1.6L EcoBoost (132kW/180PS) - Sigma, Removal and Installation).

For 1.6L Duratec-16V Ti-VCT
REFER to: Powertrain Control Module (PCM) (303-14A Electronic Engine Controls - 1.6L Duratec-16V Ti-VCT (88kW/120PS) - Sigma, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



Temperature Control Is Inoperative Or Does Not Operate Correctly


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

Temperature Door Actuator,
REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description (412-00 Climate Control System - General Information, Description and Operation).



  Diagnostic Trouble Code (DTC) Fault Trigger Conditions


DTC Description Fault Trigger Conditions
B1081:11 Left Temperature Damper Motor: Circuit Short To Ground The HVAC control module senses lower than expected voltage on the motor circuits, indicating a short to ground.
B1081:12 Left Temperature Damper Motor: Circuit Short To Battery The HVAC control module senses greater than expected voltage on the motor circuits, indicating a short to voltage.


Possible Sources

Visual Inspection and Diagnostic Pre-checks


PINPOINT TEST K : TEMPERATURE CONTROL IS INOPERATIVE OR DOES NOT OPERATE CORRECTLY
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
K1   CHECK THE TEMPERATURE DOOR ACTUATOR CIRCUITS FOR A SHORT TO VOLTAGE
  • Disconnect HVAC control module C228A .
  • Disconnect Temperature Door Actuator C2092 .
  • Disconnect Air Distribution Door Actuator C236 .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2092-1   Ground
      C2092-2   Ground
      C2092-3   Ground
      C2092-4   Ground
      C2092-6   Ground



Is there any voltage present?

Yes REPAIR the circuit in question.
No GO to K2


K2   CHECK THE TEMPERATURE DOOR ACTUATOR CIRCUITS FOR A SHORT TO GROUND
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2092-1   Ground
      C2092-2   Ground
      C2092-3   Ground
      C2092-4   Ground
      C2092-6   Ground



Are the resistances greater than 10,000 ohms?

Yes GO to K3
No REPAIR the circuit in question.


K3   CHECK THE TEMPERATURE DOOR ACTUATOR CIRCUITS FOR AN OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2092-1   C228A-6
      C2092-2   C228A-12
      C2092-3   C228A-13
      C2092-4   C228A-14
      C2092-6   C228A-5



Are the resistances less than 3 ohms?

Yes GO to K4
No REPAIR the circuit in question.


K4   CHECK THE TEMPERATURE DOOR ACTUATOR CIRCUITS FOR A SHORT TOGETHER
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2092-1   C2092-2
      C2092-1   C2092-3
      C2092-1   C2092-4
      C2092-1   C2092-6
      C2092-2   C2092-3
      C2092-2   C2092-4
      C2092-2   C2092-6
      C2092-3   C2092-4
      C2092-3   C2092-6
      C2092-4   C2092-6



Are the resistances less than 3 ohms?

Yes GO to K5
No REPAIR the circuit in question.


K5   CHECK FOR CORRECT TEMPERATURE DOOR ACTUATOR OPERATION
  • Ignition OFF.
  • Inspect the disconnected connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect all disconnected connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes INSTALL a new temperature door actuator.
REFER to: Temperature Door Actuator (412-00 Climate Control System - General Information, Removal and Installation).
TEST the system for normal operation. If the concern is still present, GO to K6
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.


K6   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



The Blower Motor Is Inoperative


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

Air Handling,
REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description (412-00 Climate Control System - General Information, Description and Operation).



  Diagnostic Trouble Code (DTC) Fault Trigger Conditions


DTC Description Fault Trigger Conditions
B10B9:12 Blower Control: Circuit Short to Battery This DTC sets when the HVAC control module senses excessive voltage on the blower motor control target speed signal circuit, indicating a short directly to voltage.
B10B9:14 Blower Control: Circuit Short to Ground or Open This DTC sets when the HVAC control module senses no voltage on the blower motor control target speed signal circuit, indicating an open or a short directly to ground.


Possible Sources

Visual Inspection and Diagnostic Pre-checks


PINPOINT TEST L : THE BLOWER MOTOR IS INOPERATIVE
NOTICE: The following Pinpoint Test uses a test light to simulate normal circuit loads. Use only a Rotunda Test Lamp (SGT27000) or 250-300mA incandescent bulb test lamp. To avoid connector terminal damage, use the Rotunda Flex Probe kit for the test lamp probe connection to the vehicle. Do not use the test lamp probe directly on any connector.
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
L1   CHECK THE BLOWER MOTOR RELAY FUNCTIONALITY
  • Install a known good blower motor relay.

Does the blower motor function correctly?

Yes INSTALL a new blower motor relay.
No GO to L2


L2   CHECK BLOWER MOTOR WITH A FUSED JUMPER WIRE
  • Ignition OFF.
  • Disconnect Blower Motor C2004 .
  • Connect a fused jumper wire between:


    Positive Lead Measurement / Action Negative Lead

    Blower motor C2004-1, component side

    Battery positive post





    Positive Lead Measurement / Action Negative Lead

    Blower motor C2004-2, component side

    Battery negative post



Does the blower motor operate?

Yes REMOVE the fused jumper wires. GO to L3
No INSTALL a new blower motor.
REFER to: Blower Motor (412-00 Climate Control System - General Information, Removal and Installation).


L3   CHECK THE BLOWER MOTOR RELAY COIL GROUND CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect Blower Motor Relay.
  • Connect a test light between:


    Positive Lead Measurement / Action Negative Lead

    Battery positive post

    Blower motor relay socket 2



Does the test light illuminate?

Yes GO to L4
No REPAIR the circuit.


L4   CHECK THE BLOWER MOTOR RELAY COIL AND SWITCH CONTACT SUPPLY VOLTAGES
  • Ignition ON.
  • Connect a test light between:


    Positive Lead Measurement / Action Negative Lead

    Blower motor relay socket 1

    Blower motor relay socket 2

    Blower motor relay socket 3

    Blower motor relay socket 2



Does the test light illuminate?

Yes GO to L5
No For blower motor relay socket 1, VERIFY CJB fuse 21 (7.5A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the Wiring Diagrams manual to identify the possible causes of the circuit short.
For blower motor relay socket 3, VERIFY BJB fuse 4 (40A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the Wiring Diagrams manual to identify the possible causes of the circuit short.


L5   CHECK THE BLOWER MOTOR SPEED CONTROL VOLTAGE CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect Blower Motor Speed Control C297A .
  • Measure:


    Positive Lead Measurement / Action Negative Lead

    Blower motor relay socket 5     		  C297A-4



Is the resistance less than 3 ohms?

Yes GO to L6
No REPAIR the circuit.


L6   CHECK THE BLOWER MOTOR SPEED CONTROL GROUND CIRCUIT FOR AN OPEN



  • Positive Lead Measurement / Action Negative Lead
      C297A-2   Ground



Is the resistance less than 3 ohms?

Yes GO to L7
No REPAIR the circuit.


L7   CHECK THE BLOWER CONTROL PWM (PULSE WIDTH MODULATION) CIRCUIT FOR A SHORT TO VOLTAGE
  • Disconnect HVAC control module C228B .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C297A-3   Ground



Is any voltage present?

Yes REPAIR the circuit.
No GO to L8


L8   CHECK THE BLOWER CONTROL PWM (PULSE WIDTH MODULATION) CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C297A-3   Ground



Is the resistance greater than 10,000 ohms?

Yes GO to L9
No REPAIR the circuit.


L9   CHECK THE BLOWER CONTROL PWM (PULSE WIDTH MODULATION) CIRCUIT FOR AN OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C297A-3   C228B-18



Is the resistance less than 3 ohms?

Yes GO to L10
No REPAIR the circuit.


L10   CHECK THE BLOWER MOTOR CIRCUITS FOR SHORT TO VOLTAGE
  • Disconnect Blower Motor Speed Control C297B .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C297B-1   Ground
      C297B-2   Ground



Is any voltage present?

Yes REPAIR the affected circuit.
No GO to L11


L11   CHECK THE BLOWER MOTOR CIRCUITS FOR SHORT TO GROUND
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C297B-1   Ground
      C297B-2   Ground



Are the resistances greater than 10,000 ohms?

Yes GO to L12
No REPAIR the affected circuit.


L12   CHECK THE BLOWER MOTOR CIRCUITS FOR ON OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C297B-1   C2004-1
      C297B-2   C2004-2



Are the resistances less than 3 ohms?

Yes GO to L13
No REPAIR the affected circuit.


L13   CHECK THE BLOWER MOTOR CIRCUITS FOR A SHORT TOGETHER
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2004-1   C2004-2



Is the resistance greater than 10,000 ohms?

Yes GO to L14
No REPAIR the circuits.


L14   CHECK FOR CORRECT BLOWER MOTOR SPEED CONTROL OPERATION
  • Ignition OFF.
  • Disconnect and inspect all blower motor speed control connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the blower motor speed control connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes INSTALL a new blower motor speed control.
REFER to: Blower Motor Speed Control - Vehicles With: Electronic Automatic Temperature Control (EATC) (412-00 Climate Control System - General Information, Removal and Installation).
TEST the system for normal operation. If the concern is still present, GO to L15
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.


L15   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



The Blower Motor Does Not Operate Correctly


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

Air handling,
REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description (412-00 Climate Control System - General Information, Description and Operation).


PINPOINT TEST M : THE BLOWER MOTOR DOES NOT OPERATE CORRECTLY
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
M1   CHECK THE HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE FOR DIAGNOSTIC TROUBLE CODES (DTCS)
  • Ignition ON.
  • Using a diagnostic scan tool, perform HVAC control module self-test.

Are any Diagnostic Trouble Codes (DTCs) present?

Yes REFER to the Diagnostic Trouble Code Charts in this section.
No GO to M2


M2   VERIFY THE BLOWER MOTOR OPERATION
  • Press the panel button on the HVAC controls.
  • Adjust the blower motor speed to LO and then to HI.

Does the blower motor operate in any position?

Yes If the blower motor operates in HI setting only, GO to M3
If the blower motor is always ON, CARRY OUT the Relay - Micro ISO component test on the blower motor relay.
Refer to Wiring Diagrams Cell 149 for schematic and connector information.
If the relay tests OK, GO to M5
No GO to Pinpoint Test L


M3   CHECK THE BLOWER MOTOR VOLTAGE CIRCUIT FOR A SHORT TO VOLTAGE
  • Disconnect Blower Motor C2004 .
  • Disconnect Blower Motor Speed Control C297B .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C297B-1   Ground



Is any voltage present?

Yes REPAIR the circuit.
No GO to M4


M4   CHECK THE BLOWER MOTOR GROUND CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C297B-2   Ground



Is the resistance greater than 10,000 ohms?

Yes GO to M5
No REPAIR the circuit.


M5   CHECK THE BLOWER CONTROL PWM (PULSE WIDTH MODULATION) CIRCUIT FOR AN OPEN
  • Disconnect Blower Motor Speed Control C297A .
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C297A-3   C228B-18



Is the resistance less than 3 ohms?

Yes GO to M6
No REPAIR the circuit.


M6   CHECK FOR CORRECT BLOWER MOTOR SPEED CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all blower motor speed control connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the blower motor speed control connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes INSTALL a new blower motor speed control.
REFER to: Blower Motor Speed Control - Vehicles With: Electronic Automatic Temperature Control (EATC) (412-00 Climate Control System - General Information, Removal and Installation).
TEST the system for normal operation. If the concern is still present, GO to M7
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.


M7   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



B1B71:11, B1B71:13


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

The evaporator temperature sensor,
REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description (412-00 Climate Control System - General Information, Description and Operation).



  Diagnostic Trouble Code (DTC) Fault Trigger Conditions


DTC Description Fault Trigger Conditions
B1B71:11 Evaporator Temperature Sensor: Circuit Short to Ground The IPC senses lower than expected voltage on the sensor feedback circuit, indicating a short to ground.
B1B71:13 Evaporator Temperature Sensor: Circuit Open The IPC senses greater than expected voltage on the sensor feedback circuit, indicating an open circuit or sensor.


Possible Sources


PINPOINT TEST N : B1B71:11, B1B71:13
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
N1   CHECK THE IPC (INSTRUMENT PANEL CLUSTER) OUTPUT VOLTAGE TO THE EVAPORATOR TEMPERATURE SENSOR
  • Ignition OFF.
  • Disconnect Evaporator Temperature Sensor C296 .
  • Ignition ON.
  • Select PANEL and press the A/C button (indicator on) on the HVAC controls.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C296-1   C296-3



Is the voltage between 4.7 and 5.1 volts?

Yes GO to N2
No GO to N3


N2   CHECK THE EVAPORATOR TEMPERATURE SENSOR
  • Ignition OFF.
  • Allow enough time for the evaporator to stabilize to the ambient temperature.
  • Measure:


    Positive Lead Measurement / Action Negative Lead

    C296-1 (component side)

    C296-3 (component side)


  • Compare the resistance values to the table below:


    Ambient Temperature Resistance
    0-10°C (32-50°F) 5,892-9,893 ohms
    10-20°C (50-68°F) 3,689-6,048 ohms
    20-25°C (68-77°F) 2,950-3,805 ohms
    25-30°C (77-86°F) 2,374-3,050 ohms
    30-35°C (86-95°F) 1,923-2,460 ohms
    35-40°C (95-104°F) 1,566-1,996 ohms
    40-50°C (104-122°F) 1,057-1,630 ohms



Did the evaporator temperature sensor test OK?

Yes GO to N7
No INSTALL a new evaporator temperature sensor.
REFER to: Evaporator Temperature Sensor (412-00 Climate Control System - General Information, Removal and Installation).


N3   CHECK THE EVAPORATOR TEMPERATURE SENSOR CIRCUITS FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect IPC C220A .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C296-1   Ground
      C296-3   Ground



Is there any voltage present?

Yes REPAIR the affected circuits.
No GO to N4


N4   CHECK THE EVAPORATOR TEMPERATURE SENSOR CIRCUITS FOR A SHORT TO GROUND
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C296-1   Ground
      C296-3   Ground



Are the resistances greater than 10,000 ohms?

Yes GO to N5
No REPAIR the affected circuits.


N5   CHECK THE EVAPORATOR TEMPERATURE SENSOR CIRCUITS FOR AN OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C220A-24   C296-2
      C220A-26   C296-1



Are the resistances less than 3 ohms?

Yes GO to N6
No REPAIR the affected circuits.


N6   CHECK THE EVAPORATOR TEMPERATURE SENSOR CIRCUITS FOR A SHORT TOGETHER
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C296-1   C296-3



Is the resistance less than 10,000 ohms?

Yes GO to N7
No REPAIR the circuits.


N7   CHECK THE IPC (INSTRUMENT PANEL CLUSTER) OPERATION
  • Ignition OFF.
  • Disconnect and inspect the IPC connector.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the IPC connector. Make sure it seats and latches correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new IPC .
REFER to: Instrument Panel Cluster (IPC) (413-01 Instrumentation, Message Center and Warning Chimes, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



B105A:11, B105A:15, B1A61:11, B1A61:15


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

In-vehicle temperature sensor,
REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description (412-00 Climate Control System - General Information, Description and Operation).



  Diagnostic Trouble Code (DTC) Fault Trigger Conditions


DTC Description Fault Trigger Conditions
B105A:11 Cabin Temperature Sensor Fan: Circuit Short to Ground The HVAC control module senses lower than expected voltage on the sensor feedback circuit, indicating a short to ground.
B105A:15 Cabin Temperature Sensor Fan: Circuit Short to Battery or Open The HVAC control module senses greater than expected voltage on the sensor feedback circuit, indicating a short to voltage or an open circuit or sensor.
B1A61:11 Cabin Temperature Sensor: Circuit Short to Ground The HVAC control module senses lower than expected voltage on the sensor feedback circuit, indicating a short to ground.
B1A61:15 Cabin Temperature Sensor: Circuit Short to Battery or Open The HVAC control module senses lower than expected voltage on the sensor feedback circuit, indicating a short to voltage or an open circuit or sensor.


Possible Sources


PINPOINT TEST O : B105A:11, B105A:15, B1A61:11, B1A61:15
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
O1   CHECK THE HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OUTPUT VOLTAGE TO THE IN-VEHICLE TEMPERATURE SENSOR
  • Ignition OFF.
  • Disconnect In-Vehicle Temperature Sensor C233 .
  • Ignition ON.
  • Select PANEL on the HVAC controls.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C233-1   C233-3



Is the voltage between 4.7 and 5.1 volts?

Yes GO to O2
No GO to O3


O2   CHECK THE IN-VEHICLE TEMPERATURE SENSOR RESISTANCE
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead

    C233-4 (component side)

    C233-6 (component side)


  • Compare the resistance values to the table below:


    Ambient Temperature Approximate Resistance
    -40°C (-40°F) 901,490 ohms
    -15°C (5°F) 208,450 ohms
    0°C (32°F) 95,560 ohms
    15°C (59°F) 46,750 ohms
    25°C (77°F) 30,000 ohms
    35°C (95°F) 19,720 ohms
    60°C (140°F) 7,592 ohms
    85°C (185°F) 3,286 ohms



Did the in-vehicle temperature sensor test OK?

Yes GO to O3
No INSTALL a new in-vehicle temperature sensor.
REFER to: In-Vehicle Temperature Sensor (412-00 Climate Control System - General Information, Removal and Installation).


O3   CHECK THE IN-VEHICLE TEMPERATURE SENSOR CIRCUITS FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect HVAC control module C228B .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C233-1   Ground
      C233-3   Ground
      C233-4   Ground
      C233-6   Ground



Is any voltage present?

Yes REPAIR the affected circuits.
No GO to O4


O4   CHECK THE IN-VEHICLE TEMPERATURE SENSOR CIRCUITS FOR A SHORT TO GROUND
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C233-1   Ground
      C233-3   Ground
      C233-4   Ground
      C233-6   Ground



Are the resistances greater than 10,000 ohms?

Yes GO to O5
No REPAIR the affected circuits.


O5   CHECK THE IN-VEHICLE TEMPERATURE SENSOR CIRCUITS FOR AN OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C233-1   C228B-8
      C233-3   C228B-9
      C233-4   C228B-11
      C233-6   C228B-3



Are the resistances less than 3 ohms?

Yes GO to O6
No REPAIR the affected circuits.


O6   CHECK THE IN-VEHICLE TEMPERATURE SENSOR CIRCUITS FOR A SHORT TOGETHER
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C233-1   C233-3
      C233-1   C233-4
      C233-1   C233-6
      C233-3   C233-4
      C233-3   C233-6
      C233-4   C233-6



Are the resistances greater than 10,000 ohms?

Yes GO to S1
No REPAIR the affected circuits.


O7   CHECK FOR CORRECT IN-VEHICLE TEMPERATURE SENSOR OPERATION
  • Ignition OFF.
  • Inspect the disconnected in-vehicle temperature sensor connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect all in-vehicle temperature sensor disconnected connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes INSTALL a new in-vehicle temperature sensor.
REFER to: In-Vehicle Temperature Sensor (412-00 Climate Control System - General Information, Removal and Installation).
TEST the system for normal operation. If the concern is still present, GO to O8
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.


O8   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



B1A63:11, B1A63:15, B1A64:11, B1A64:15


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

Sunload sensor,
REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description (412-00 Climate Control System - General Information, Description and Operation).



  Diagnostic Trouble Code (DTC) Fault Trigger Conditions


DTC Description Fault Trigger Conditions
B1A63:11 Right Solar Sensor: Circuit Short to Ground This DTC sets when the HVAC control module senses lower than expected voltage on the RH sensor feedback circuit, indicating a short to ground.
B1A63:15 Right Solar Sensor: Circuit Short to Battery or Open This DTC sets when the HVAC control module senses greater than expected voltage on the RH sensor feedback circuit, indicating a short to voltage or an open circuit or sensor.
B1A64:11 Left Solar Sensor: Circuit Short to Ground This DTC sets when the HVAC control module senses lower than expected voltage on the LH sensor feedback circuit, indicating a short to ground.
B1A64:15 Left Solar Sensor: Circuit Short to Battery or Open This DTC sets when the HVAC control module senses greater than expected voltage on the LH sensor feedback circuit, indicating a short to voltage or an open circuit or sensor.


Possible Sources

Visual Inspection and Diagnostic Pre-checks

Inspect loose or corroded HVAC control module and sunload sensor connections.


PINPOINT TEST P : B1A63:11, B1A63:15, B1A64:11, B1A64:15
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
P1   CHECK THE SUNLOAD SENSOR CIRCUITS FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect HVAC control module C228B .
  • Disconnect Sunload Sensor C2360 .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2360-1   Ground
      C2360-2   Ground
      C2360-3   Ground



Is any voltage present?

Yes REPAIR the affected circuits.
No GO to P2


P2   CHECK THE SUNLOAD SENSOR CIRCUITS FOR A SHORT TO GROUND
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2360-1   Ground
      C2360-2   Ground
      C2360-3   Ground



Are the resistances greater than 10,000 ohms?

Yes GO to P3
No REPAIR the affected circuits.


P3   CHECK THE SUNLOAD SENSOR CIRCUITS FOR AN OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2360-1   C228B-2
      C2360-2   C228B-1
      C2360-3   C228B-12



Are the resistances less than 3 ohms?

Yes GO to P4
No REPAIR the affected circuits.


P4   CHECK THE SUNLOAD SENSOR CIRCUITS FOR A SHORT TOGETHER
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2360-1   C2360-2
      C2360-1   C2360-3
      C2360-2   C2360-3



Are the resistances greater than 10,000 ohms?

Yes GO to P5
No REPAIR the circuits.


P5   CHECK FOR CORRECT SUNLOAD SENSOR OPERATION
  • Ignition OFF.
  • Inspect the disconnected sunload sensor connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect all disconnected sunload sensor connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes INSTALL a new sunload sensor.
REFER to: Sunload Sensor - Vehicles With: Electronic Automatic Temperature Control (EATC) (412-00 Climate Control System - General Information, Removal and Installation).
TEST the system for normal operation. If the concern is still present, GO to P6
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.


P6   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



B10B5:11, B10B5:15


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

Sensor inputs, center register air discharge temperature sensor,
REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description (412-00 Climate Control System - General Information, Description and Operation).



  Diagnostic Trouble Code (DTC) Fault Trigger Conditions


DTC Description Fault Trigger Conditions
B10B5:11 Left Panel Air Discharge Temperature: Circuit Short To Ground This DTC sets when the HVAC control module senses lower than expected voltage on the sensor feedback circuit, indicating a short to ground.
B10B5:15 Left Panel Air Discharge Temperature: Circuit Short To Battery or Open This DTC sets when the HVAC control module senses greater than expected voltage on the sensor feedback circuit, indicating a short to voltage or an open circuit or sensor.


Possible Sources

Visual Inspection and Diagnostic Pre-checks

Inspect loose or corroded HVAC control module and center register air discharge temperature sensor connections.


PINPOINT TEST Q : B10B5:11, B10B5:15
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
Q1   CHECK THE CENTER REGISTER AIR DISCHARGE TEMPERATURE SENSOR CIRCUITS FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect HVAC control module C228B .
  • Disconnect Center Register Air Discharge Temperature Sensor C2438 .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2438-1   Ground
      C2438-3   Ground



Is any voltage present?

Yes REPAIR the affected circuits.
No GO to Q2


Q2   CHECK THE CENTER REGISTER AIR DISCHARGE TEMPERATURE SENSOR CIRCUITS FOR A SHORT TO GROUND
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2438-1   Ground
      C2438-3   Ground



Are the resistances greater than 10,000 ohms?

Yes GO to Q3
No REPAIR the affected circuits.


Q3   CHECK THE CENTER REGISTER AIR DISCHARGE TEMPERATURE SENSOR CIRCUITS FOR AN OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2438-1   C228B-16
      C2438-3   C228B-15



Are the resistances less than 3 ohms?

Yes GO to Q4
No REPAIR the affected circuits.


Q4   CHECK THE CENTER REGISTER AIR DISCHARGE TEMPERATURE SENSOR CIRCUITS FOR A SHORT TOGETHER
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2438-1   C2438-3



Is the resistance greater than 10,000 ohms?

Yes GO to Q5
No REPAIR the circuits.


Q5   CHECK FOR CORRECT CENTER REGISTER AIR DISCHARGE TEMPERATURE SENSOR OPERATION
  • Ignition OFF.
  • Inspect the disconnected center register air discharge temperature sensor connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect all disconnected center register air discharge temperature sensor connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes INSTALL a new center register air discharge temperature sensor.
REFER to: Center Register Air Discharge Temperature Sensor (412-00 Climate Control System - General Information, Removal and Installation).
TEST the system for normal operation. If the concern is still present, GO to Q6
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.


Q6   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



B10B6:11, B10B6:15


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

Sensor inputs, footwell air discharge temperature sensor (footwell air discharge temperature sensor),
REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description (412-00 Climate Control System - General Information, Description and Operation).



  Diagnostic Trouble Code (DTC) Fault Trigger Conditions


DTC Description Fault Trigger Conditions
B10B6:11 Left Floor Air Discharge Temperature: Circuit Short To Ground This DTC sets when the HVAC control module senses lower than expected voltage on the LH sensor feedback circuit, indicating a short to ground.
B10B6:15 Left Floor Air Discharge Temperature: Circuit Short To Battery or Open This DTC sets when the HVAC control module senses greater than expected voltage on the LH sensor feedback circuit, indicating a short to voltage or an open circuit or sensor.


Possible Sources

Visual Inspection and Diagnostic Pre-checks

Inspect loose or corroded HVAC control module and footwell air discharge temperature sensor connections.


PINPOINT TEST R : B10B6:11, B10B6:15
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
R1   CHECK THE FOOTWELL AIR DISCHARGE TEMPERATURE SENSOR CIRCUITS FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect HVAC control module C228B .
  • Disconnect Footwell Discharge Air Temperature Sensor C2436 .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2436-1   Ground
      C2436-3   Ground



Is any voltage present?

Yes REPAIR the affected circuits.
No GO to R2


R2   CHECK THE FOOTWELL AIR DISCHARGE TEMPERATURE SENSOR CIRCUITS FOR A SHORT TO GROUND
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2436-1   Ground
      C2436-3   Ground



Are the resistances greater than 10,000 ohms?

Yes GO to R3
No REPAIR the affected circuits.


R3   CHECK THE FOOTWELL AIR DISCHARGE TEMPERATURE SENSOR CIRCUITS FOR AN OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2436-1   C228B-7
      C2436-3   C228B-6



Are the resistances less than 3 ohms?

Yes GO to R4
No REPAIR the affected circuits.


R4   CHECK THE FOOTWELL AIR DISCHARGE TEMPERATURE SENSOR CIRCUITS FOR A SHORT TOGETHER
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C2436-1   C2436-3



Is the resistance greater than 10,000 ohms?

Yes GO to R5
No REPAIR the circuits.


R5   CHECK FOR CORRECT FOOTWELL AIR DISCHARGE TEMPERATURE SENSOR OPERATION
  • Ignition OFF.
  • Inspect the disconnected footwell air discharge temperature sensor connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect all disconnected footwell air discharge temperature sensor connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes INSTALL a new footwell air discharge temperature sensor.
REFER to: Footwell Air Discharge Temperature Sensor - Vehicles With: Electronic Automatic Temperature Control (EATC) (412-00 Climate Control System - General Information, Removal and Installation).
TEST the system for normal operation. If the concern is still present, GO to R6
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.


R6   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



B1A59:11, B1A59:12


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

A 5-volt reference voltage is supplied to the temperature and air distribution door actuators from the HVAC control module.



  Diagnostic Trouble Code (DTC) Fault Trigger Conditions


DTC Description Fault Trigger Conditions
B1A59:11 Sensor 5 Volt Supply: Circuit Short To Ground This DTC sets when the HVAC control module senses lower than expected voltage on the reference voltage circuit, indicating a short to ground.
B1A59:12 Sensor 5 Volt Supply: Circuit Short To Battery This DTC sets when the HVAC control module senses greater than expected voltage on the reference voltage circuit, indicating a short to voltage or an open circuit or actuator.


Possible Sources

Visual Inspection and Diagnostic Pre-checks

Inspect loose or corroded HVAC control module connections.


PINPOINT TEST S : B1A59:11, B1A59:12
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
S1   CHECK THE HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE FOR DIAGNOSTIC TROUBLE CODES (DTCS)
  • Ignition ON.
  • Using a diagnostic scan tool, perform HVAC control module self-test.

Is DTC B1A59:11 or B1A59:12 present?

Yes For B1A59:11, GO to S2
For B1A59:12, GO to S3
No For all other Diagnostic Trouble Codes (DTCs), REFER to the HVAC control module DTC chart in this section.


S2   CHECK THE REFERENCE VOLTAGE CIRCUIT AND ACTUATORS RESISTANCE
  • Ignition OFF.
  • Disconnect HVAC control module C228A .
  • While measuring the resistance, disconnect the following components one at a time, in order. Stop disconnecting components if the measured resistance rises above 200 ohms.
    • Temperature door actuator
    • Air distribution door actuator
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C228A-13   Ground



Did the resistance rise above 200 ohms?

Yes INSTALL a new actuator (the last one to be disconnected).
REFER to: Temperature Door Actuator (412-00 Climate Control System - General Information, Removal and Installation).
or REFER to: Air Distribution Door Actuator (412-00 Climate Control System - General Information, Removal and Installation).
No REPAIR the circuit.


S3   CHECK THE REFERENCE VOLTAGE CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect HVAC control module C228A .
  • Disconnect Temperature Door Actuator C2092 .
  • Disconnect Air Distribution Door Actuator C236 .
  • Ignition ON.



  • Positive Lead Measurement / Action Negative Lead
      C228A-13   Ground



Is any voltage present?

Yes REPAIR the circuit.
No GO to S4


S4   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



U0140:00


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

Control Logic,
REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description (412-00 Climate Control System - General Information, Description and Operation).



  DTC Fault Trigger Conditions


DTC Description Fault Trigger Conditions
U0140:00 Lost Communication With Body Control Module: No Sub-Type Information This DTC sets in the HVAC control module if data messages received from the BCM are missing.


Possible Sources


PINPOINT TEST T : U0140:00
T1   CHECK THE COMMUNICATION NETWORK
  • Ignition ON.
  • Using a diagnostic scan tool, perform a network test.

Does the BCM pass the network test?

Yes GO to T2
No DIAGNOSE the no communication with the BCM .
REFER to: Communications Network (418-00 Module Communications Network, Diagnosis and Testing).


T2   RETRIEVE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE BCM (BODY CONTROL MODULE) SELF-TEST
  • Using a diagnostic scan tool, perform BCM self-test.

Is DTC U3003:16 or DTC U3003:17 recorded?

Yes
REFER to: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Diagnosis and Testing).
No GO to T3


T3   RETRIEVE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE SELF-TEST
  • Check for recorded Diagnostic Trouble Codes (DTCs) from the HVAC module self-test.

Is DTC U3006:16 or DTC U3006:17 recorded?

Yes GO to Pinpoint Test V
No GO to T4


T4   RECHECK THE HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE DIAGNOSTIC TROUBLE CODES (DTCS)
  • Clear all Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • Ignition ON.
  • Repeat the HVAC module self-test.

Is DTC U0140:00 retrieved again?

Yes GO to T5
No The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.


T5   CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0140:00 SET IN OTHER MODULES
  • Using a diagnostic scan tool, clear all Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • Wait 10 seconds.
  • Ignition ON.
  • Using a diagnostic scan tool, retrieve all Continuous Memory Diagnostic Trouble Codes (CMDTCs).

Is DTC U0140:00 set in any other modules?

Yes GO to T6
No GO to T7


T6   CHECK FOR CORRECT BCM (BODY CONTROL MODULE) OPERATION
  • Ignition OFF.
  • Disconnect and inspect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the BCM connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new BCM .
REFER to: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.


T7   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



U0155:00


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

Control Logic,
REFER to: Climate Control System - Vehicles With: Electronic Automatic Temperature Control (EATC) - System Operation and Component Description (412-00 Climate Control System - General Information, Description and Operation).



  DTC Fault Trigger Conditions


DTC Description Fault Trigger Conditions
U0155:00 Lost Communication With Instrument Panel Cluster (IPC) Control Module: No Sub Type Information This DTC sets in the HVAC control module if data messages received from the IPC module are missing.


Possible Sources


PINPOINT TEST U : U0155:00
U1   CHECK THE COMMUNICATION NETWORK
  • Ignition ON.
  • Using a diagnostic scan tool, perform network test.

Does the IPC pass the network test?

Yes GO to U2
No
REFER to: Communications Network (418-00 Module Communications Network, Diagnosis and Testing).


U2   RETRIEVE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE IPC (INSTRUMENT PANEL CLUSTER) SELF-TEST
  • Using a diagnostic scan tool, perform IPC self-test.
  • Check for Diagnostic Trouble Codes (DTCs) from the IPC self-test.

Is DTC U3006:16 or DTC U3006:17 recorded?

Yes
REFER to: Instrumentation, Message Center and Warning Chimes (413-01 Instrumentation, Message Center and Warning Chimes, Diagnosis and Testing).
No GO to U3


U3   RETRIEVE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE SELF-TEST
  • Check for recorded Diagnostic Trouble Codes (DTCs) from the HVAC module self-test.

Is DTC U3006:16 or DTC U3006:17 recorded?

Yes GO to Pinpoint Test V
No GO to U4


U4   RECHECK THE HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE DIAGNOSTIC TROUBLE CODES (DTCS)
  • Clear all Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • Ignition ON.
  • Repeat the HVAC module self-test.

Is DTC U0155:00 retrieved again?

Yes GO to U5
No The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.


U5   CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0155:00 SET IN OTHER MODULES
  • Using a diagnostic scan tool, clear all Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • Wait 10 seconds.
  • Ignition ON.
  • Using a diagnostic scan tool, retrieve all Continuous Memory Diagnostic Trouble Codes (CMDTCs).

Is DTC U0155:00 set in any other modules?

Yes GO to U6
No GO to U7


U6   CHECK FOR CORRECT IPC (INSTRUMENT PANEL CLUSTER) OPERATION
  • Ignition OFF.
  • Disconnect and inspect the IPC connector.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the IPC connector. Make sure it seats and latches correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW Technical Service Bulletin (TSB) instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new IPC .
REFER to: Instrument Panel Cluster (IPC) (413-01 Instrumentation, Message Center and Warning Chimes, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.


U7   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



U3006:16, U3006:17


Refer to Wiring Diagrams Cell 55 for schematic and connector information.

Normal Operation and Fault Conditions

The HVAC control module is supplied constant voltage and ground. Excessive resistance or an open in one or more of these circuits, a discharged battery or an inoperative charging system will result in the HVAC control module setting a DTC .



  DTC Fault Trigger Conditions


DTC Description Fault Trigger Conditions
U3006:16 Control Module Input Power "A": Circuit Voltage Below Threshold This DTC sets when the HVAC control module senses lower than expected voltage.
U3006:17 Control Module Input Power "A": Circuit Voltage Above Threshold This DTC sets when the HVAC control module senses greater than expected voltage.


Possible Sources


PINPOINT TEST V : U3006:16, U3006:17
NOTICE: Use the Rotunda Flex Probe kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
V1   CARRY OUT THE HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE SELF-TEST
  • Ignition ON.
  • Using a diagnostic scan tool, clear Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • Wait 10 seconds.
  • Start the engine.
  • Using a diagnostic scan tool, perform HVAC control module self-test.

Is DTC U3006:16 or U3006:17 still present?

Yes GO to V2
No The system is operating correctly at this time. The DTC may have been set due to a previous low battery voltage condition.


V2   RETRIEVE PCM (POWERTRAIN CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Start the engine.
  • Using a diagnostic scan tool, perform PCM self-test.

Are any charging system Diagnostic Trouble Codes (DTCs) present in the PCM ?

Yes
REFER to: Charging System - 1.6L EcoBoost (132kW/180PS) - Sigma (414-00 Charging System - General Information, Diagnosis and Testing).


REFER to: Charging System - 1.6L Duratec-16V Ti-VCT (88kW/120PS) - Sigma (414-00 Charging System - General Information, Diagnosis and Testing).
No GO to V3


V3   CHECK BATTERY CONDITION
  • Ignition OFF.
  • Carry out the battery condition test.
    REFER to: Battery (414-01 Battery, Mounting and Cables, Diagnosis and Testing).

Does the battery pass the condition test?

Yes For DTC U3006:16, GO to V4
For DTC U3006:17, GO to V6
No INSTALL a new battery.
REFER to: Battery (414-01 Battery, Mounting and Cables, Removal and Installation).


V4   CHECK THE HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE VOLTAGE SUPPLY CIRCUIT FOR HIGH RESISTANCE
  • Ignition OFF.
  • Disconnect HVAC Control Module C228A .
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C228A-10   Ground



Is the voltage greater than 11 volts?

Yes GO to V5
No VERIFY CJB fuse 12 (7.5A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the Wiring Diagrams manual to identify the possible causes of the circuit short.


V5   CHECK THE HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE GROUND CIRCUIT FOR HIGH RESISTANCE
  • Ignition OFF.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C228A-3   Ground



Is the resistance less than 3 ohms?

Yes GO to V6
No REPAIR the circuit.


V6   CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect all HVAC control module connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Connect the HVAC control module connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?

Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module.
REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module (412-00 Climate Control System - General Information, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.



Refrigerant System Tests Diagnostic Table

  1. NOTE: The following table is used to guide diagnosis of the refrigerant system if operating pressures are outside normal limits.

    NOTE: Variable compressors operate at lower pressures and are dependent on correct system charge for normal operation.

    Refer to the chart below.



High (Discharge) Pressure Low (Suction) Pressure Component — Causes
High Normal to High
  • Condenser — inadequate airflow.
  • Engine — overheating.
Normal to High Normal
  • Refrigerant overcharge — air in refrigerant.
Normal to Low High
  • A/C Compressor — low performance.
    • Before condemning the A/C compressor verify the refrigerant system has the correct system charge.
Normal to Low Normal to High
  • A/C suction line — partially restricted or plugged. a
Normal to Low Low
  • Low refrigerant charge — leak in system.
  • A/C suction line — partially restricted or plugged. b
Erratic Operation or Compressor Not Running
  • Ambient Air Temperature (AAT) sensor — poor connection.
  • A/C pressure transducer — poor connection.
  • Evaporator temperature sensor — poor connection.
  • Low refrigerant charge — leak in system.
Additional Possible Components or Causes Associated With Inadequate Compressor Operation
  • Compressor Drive Belt — loose
  • Compressor Clutch — slipping
  • Clutch Coil Open — shorted, or loose mounting
  • Control Assembly Switch — dirty contacts or sticking open
  • Clutch Wiring Circuit — high resistance, open or blown fuse
  • Compressor Operation Interrupted by Engine Computer
Additional Possible Components or Causes Associated With a Damaged Compressor
  • Incorrect Clutch Air-gap
  • Suction Accumulator — refrigerant oil bleed hose plugged
  • Refrigerant Leaks

a Low pressure reading will be normal to high if restriction is downstream of service access valve.

b Low pressure reading will be low if restriction is upstream of service access valve.




Copyright © Ford Motor Company