501-20B Supplemental Restraint System 2014 Fiesta
Diagnosis and Testing Procedure revision date: 05/6/2013

Pinpoint Test - DTC: F

B0050:11, B0050:12, B0050:13 and B0050:1D


Refer to Wiring Diagrams Cell 46 for schematic and connector information.

Normal Operation and Fault Conditions

The RCM monitors the driver safety belt buckle switch circuits for the following faults:

If a fault is detected, the RCM stores DTC B0050:11, B0050:12, B0050:13 or B0050:1D in memory and sends a message to the IPC to illuminate the airbag warning indicator.



  DTC Fault Trigger Conditions


  DTC Description Fault Trigger Conditions
B0050:11 Driver Seatbelt Sensor: Circuit Short to Ground A fault is indicated when the RCM senses a short to ground on the driver safety belt buckle switch circuit.
B0050:12 Driver Seatbelt Sensor: Circuit Short to Battery A fault is indicated when the RCM senses a short to voltage on the driver safety belt buckle switch circuit.
B0050:13 Driver Seatbelt Sensor: Circuit Open A fault is indicated when the RCM senses an open on either driver safety belt buckle switch circuit.
B0050:1D Driver Seatbelt Sensor: Circuit Current Out of Range A fault is indicated when the RCM senses current out of an acceptable range between the driver safety belt buckle switch circuits.


Possible Causes

Visual Inspection and Diagnostic Pre-checks


PINPOINT TEST A : B0050:11, B0050:12, B0050:13 AND B0050:1D
NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the pinpoint test.
NOTE: Only disconnect or reconnect SRS components when instructed to do so within a pinpoint test step. Failure to follow this instruction may result in incorrect diagnosis of the SRS .
NOTE: Always make sure the correct SRS component is being installed. Parts released for other vehicles may not be compatible even if they appear physically similar. Check the part number listed in the Ford parts catalog to make sure the correct component is being installed. If an incorrect SRS component is installed, Diagnostic Trouble Codes (DTCs) may set.
NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
A1   RETRIEVE RCM (RESTRAINTS CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Ignition ON.
  • Using a diagnostic scan tool, perform RCM self-test.

Was DTC B0050:11, B0050:12, B0050:13 or B0050:1D retrieved on-demand during self-test?

Yes This fault cannot be cleared until it is corrected and the DTC is no longer retrieved on-demand during self-test.
For DTC B0050:11 or B0050:1D, GO to A2
For DTC B0050:12, GO to A4
For DTC B0050:13, GO to A5
No This is an intermittent fault when present as a Continuous Memory Diagnostic Trouble Code (CMDTC) only. GO to A10


A2   CHECK THE DRIVER SEATBELT SENSOR DTC (DIAGNOSTIC TROUBLE CODE) FOR A FAULT STATUS CHANGE (SHORT TO GROUND OR CURRENT OUT OF RANGE INDICATED)

NOTE: This pinpoint test step attempts to change the fault reported by the RCM by inducing a different fault condition. If the reported fault changes, this indicates the RCM is functioning correctly and is not the source of the fault.

  • Ignition OFF.
  • Disconnect: Driver Safety Belt Buckle C3065.
  • Ignition ON.
  • Using a diagnostic scan tool, perform RCM self-test.
  • DIAGNOSTIC TIP: When viewing Diagnostic Trouble Codes (DTCs) with the driver safety belt buckle switch disconnected, an open circuit fault is normally retrieved.

Did the on-demand DTC change from B0050:11 or B0050:1D to B0050:13?

Yes GO to A8
No For DTC B0050:11, GO to A3
For DTC B0050:1D, GO to A9


A3   CHECK THE DRIVER SAFETY BELT BUCKLE SWITCH CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect: RCM C310A and C310B.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C3065-2   Ground



Is the resistance greater than 10,000 ohms?

Yes GO to A9
No REPAIR the circuit.
Refer to Wiring Diagrams Cell 5 for schematic and connector information.
GO to A11


A4   CHECK THE DRIVER SAFETY BELT BUCKLE SWITCH CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: RCM C310A and C310B.
  • Disconnect: Driver Side Airbag C367.
  • Disconnect: Driver Safety Belt Buckle C3065.
  • Ignition ON.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C3065-2   Ground



Is any voltage present?

Yes REPAIR the circuit.
Refer to Wiring Diagrams Cell 5 for schematic and connector information.
GO to A11
No GO to A9


A5   CHECK THE DRIVER SEATBELT SENSOR DTC (DIAGNOSTIC TROUBLE CODE) FOR A FAULT STATUS CHANGE (OPEN INDICATED)

NOTE: This pinpoint test step attempts to change the fault reported by the RCM by inducing a different fault condition. If the reported fault changes, this indicates the RCM is functioning correctly and is not the source of the fault.

  • Ignition OFF.
  • Disconnect: Driver Side Airbag C367.
  • Disconnect: Driver Safety Belt Buckle C3065.
  • Connect a fused jumper wire:


    Lead 1 Measurement / Action Lead 2
      C3065-2   C3065-1


  • Ignition ON.
  • Using a diagnostic scan tool, perform RCM self-test.
  • DIAGNOSTIC TIP: When viewing Diagnostic Trouble Codes (DTCs) with the driver safety belt buckle switch circuits shorted together, a short to ground fault is normally retrieved.

Did the on-demand DTC change from B0050:13 to B0050:11?

Yes REMOVE the fused jumper wire and GO to A8
No REMOVE the fused jumper wire and GO to A6


A6   CHECK THE DRIVER SAFETY BELT BUCKLE SWITCH CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect: RCM C310A and C310B.
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C310B-54   C3065-2



Is the resistance less than 0.5 ohm?

Yes GO to A7
No REPAIR the circuit.
Refer to Wiring Diagrams Cell 5 for schematic and connector information.
GO to A11


A7   CHECK THE DRIVER SAFETY BELT BUCKLE SWITCH GROUND CIRCUIT FOR AN OPEN
  • Measure:


    Positive Lead Measurement / Action Negative Lead
      C3065-1   C310B-53



Is the resistance less than 3 ohms?

Yes GO to A9
No REPAIR the circuit.
Refer to Wiring Diagrams Cell 5 for schematic and connector information.
GO to A11


A8   CONFIRM THE DRIVER SAFETY BELT BUCKLE SWITCH FAULT

NOTE: Make sure all SRS components and the RCM electrical connectors are connected before carrying out the self-test. If not, Diagnostic Trouble Codes (DTCs) will be recorded.

  • Ignition OFF.
  • Prior to reconnecting any previously disconnected SRS component:
    • inspect connector(s) (including any inline connectors) for pushed-out, loose or spread terminals and loose or frayed wire connections at terminals.
    • inspect wire harness for any damaged, pinched, cut or pierced wires.
    • inspect RCM C310A and C310B Connector Position Assurance (CPA) lever/lock for correct operation.
    • repair any concerns found.
      Refer to Wiring Diagrams Cell 5 for schematic and connector information.
  • Connect: RCM C310A and C310B.
  • Connect: Driver Side Airbag C367.
  • Connect: Driver Safety Belt Buckle C3065.
  • Ignition ON.
  • Using a diagnostic scan tool, perform RCM self-test.

Was the original DTC retrieved on-demand during self-test?

Yes INSTALL a new driver safety belt buckle.
REFER to: Front Safety Belt Buckle (501-20A Safety Belt System, Removal and Installation).
GO to A11
No In the process of diagnosing the fault, the fault condition has become intermittent. Do not install any new SRS components at this time. Install SRS components only when directed to do so in the pinpoint test. GO to A10


A9   CONFIRM THE RCM (RESTRAINTS CONTROL MODULE) FAULT

NOTE: Make sure all SRS components and the RCM electrical connectors are connected before carrying out the self-test. If not, Diagnostic Trouble Codes (DTCs) will be recorded.

  • Ignition OFF.
  • Prior to reconnecting any previously disconnected SRS component:
    • inspect connector(s) (including any inline connectors) for pushed-out, loose or spread terminals and loose or frayed wire connections at terminals.
    • inspect wire harness for any damaged, pinched, cut or pierced wires.
    • inspect RCM C310A and C310B Connector Position Assurance (CPA) lever/lock for correct operation.
    • repair any concerns found.
      Refer to Wiring Diagrams Cell 5 for schematic and connector information.
  • Connect: RCM C310A and C310B.
  • Connect: Driver Side Airbag C367.
  • Connect: Driver Safety Belt Buckle C3065.
  • Ignition ON.
  • Using a diagnostic scan tool, perform RCM self-test.

Was the original DTC retrieved on-demand during self-test?

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 RCM .
REFER to: Restraints Control Module (RCM) (501-20B Supplemental Restraint System, Removal and Installation).
GO to A11
No In the process of diagnosing the fault, the fault condition has become intermittent. Do not install any new SRS components at this time. Install SRS components only when directed to do so in the pinpoint test. GO to A10


A10   CHECK FOR AN INTERMITTENT FAULT
  • Ignition OFF.
  • Disconnect Driver Safety Belt Buckle C3065 .
    • Inspect connector(s) (including any inline connectors) for corrosion, loose or spread terminals and loose or frayed wire connections at terminals.
    • Inspect wire harness for any damage, pinched, cut or pierced wires.
    • Repair any concerns found.
      Refer to Wiring Diagrams Cell 5 for schematic and connector information.
  • Inspect RCM C310A and C310B Connector Position Assurance (CPA) lever/lock for correct operation.
  • Connect all previously disconnected component(s) / connector(s).
  • Ignition ON.
  • Using a diagnostic scan tool, perform RCM self-test.

Was DTC B0050:11, B0050:12, B0050:13 or B0050:1D retrieved on-demand during self-test?

Yes This fault cannot be cleared until it is corrected and the DTC is no longer retrieved on-demand during self-test.
For DTC B0050:11 or B0050:1D, GO to A2
For DTC B0050:12, GO to A4
For DTC B0050:13, GO to A5
No The fault is not present and cannot be recreated at this time. Do not install any new SRS components at this time. Install SRS components only when directed to do so in the pinpoint test. GO to A11


A11   CHECK FOR ADDITIONAL SRS (SUPPLEMENTAL RESTRAINT SYSTEM) DIAGNOSTIC TROUBLE CODES (DTCS)

WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.

  • Ignition OFF.
  • Reconnect all SRS components (if previously disconnected).
  • Ignition ON.
  • NOTE: When selecting Restraints from the Self Test menu, DTCs are retrieved from the RCM and OCSM .

    Using a diagnostic scan tool, perform Restraints self-test.

Are any RCM and/or OCSM Diagnostic Trouble Codes (DTCs) retrieved on-demand during self-test?

Yes Do not clear any Diagnostic Trouble Codes (DTCs) until all Diagnostic Trouble Codes (DTCs) have been resolved. DIAGNOSE and REPAIR the RCM and/or OCSM Diagnostic Trouble Codes (DTCs).
REFER to: Airbag Supplemental Restraint System (SRS) (501-20B Supplemental Restraint System, Diagnosis and Testing).
No CLEAR Continuous Memory Diagnostic Trouble Codes (CMDTCs) from all modules. PROVE OUT the SRS . The repair is complete. RETURN the vehicle to the customer.





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