Perimeter Anti-Theft Alarm - System Operation and Component Description

System Operation

System Diagram

Network Message Chart

  BCM Network Input Messages

Anti-Theft - Perimeter

The BCM controls the operation of the perimeter alarm. It monitors inputs from the RKE system, the passive entry system (if equipped), the power door lock system, the PATS , the ignition status and the intrusion sensor (if equipped) to determine when to arm, activate or disarm the perimeter alarm.

The BCM monitors all of the door ajar inputs, the liftgate/luggage compartment lid ajar input, the hood ajar input and the ignition status and the intrusion sensor (if equipped) to determine when to activate the perimeter alarm. When the BCM detects an input indicating an unauthorized entry into the vehicle, the BCM activates the perimeter alarm by sounding the traffic horn (or the anti-theft alarm horn if equipped) and flashing all the turn signals at regular intervals.

Arming The Perimeter Alarm

The perimeter alarm is ready to arm any time the ignition is off. The perimeter alarm pre-arms when any of the following actions are performed:

• Pressing the lock button on a programmed RKE transmitter
• Locking the doors with the door lock control switch with the door open, and then closing the door
• Locking the vehicle with a correctly cut key blade
• Locking the vehicle with the passive entry feature (if equipped)

Once the system is pre-armed, there is an 11-second countdown before the perimeter alarm is armed. Each entry point to the vehicle (hood, door and liftgate/luggage compartment lid) is armed separately and must be closed before that entry point begins the 11-second countdown to become armed. If all entry points are closed, the turn signals flash upon locking indicating that all entry points are entering the 11-second countdown.

Perimeter Alarm Activation

The perimeter alarm activates when any of the following actions are performed:

• The driver front door is opened without first receiving an unlock command from the passive entry feature (if equipped) or a programmed RKE transmitter, or unlocking the driver door using the door key cylinder.
• Any other door, the liftgate/luggage compartment lid, or the hood is opened without first receiving an electronic unlock command from the passive entry feature (if equipped) or a programmed RKE transmitter.
• The ignition transitions to RUN without a valid PATS key read received.
• The intrusion sensor detects movement interpreted as intrusive.

Disarming The Perimeter Alarm

The perimeter alarm disarms when any of the following actions are performed:

• Pressing the unlock button on a programmed RKE transmitter
• Pressing the liftgate/luggage compartment lid release button on a programmed RKE transmitter (this only inhibits the luggage compartment entry point with the rest of the vehicle remaining armed)
• Using a programmed key to change the ignition to RUN
• Unlocking the driver door using the driver door lock cylinder
• Using the passive entry feature (if equipped)

Component Description

Hood Ajar Switch

The hood ajar switch is integrated into the hood latch and not serviceable separately. When the hood is closed, the hood ajar switch is closed. When the hood is opened, the hood ajar switch is open.

The BCM sends a voltage signal to the hood ajar switch and, based on the input, the BCM determines if the hood is open or closed.

Door Ajar Switches

The door ajar switches are integrated into the door latches and not serviceable separately. When the door is closed, the door ajar switch is closed. When the door is opened, the door ajar switch is open.

The BCM sends a voltage signal to each door ajar switch and, based on the input, the BCM determines if a door is open or closed. When the BCM detects an unauthorized entry from a door, the alarm activates.

Driver Door Arm/Disarm Switch

The driver door arm/disarm switch is integrated into the driver door latch and not serviceable separately.

The BCM monitors the driver door arm/disarm switch input to pre-arm, arm or disarm the perimeter alarm. The switch is normally open. When a key is used to lock or unlock the door with the key cylinder, the switch grounds the arm or disarm voltage signal from the BCM .

Liftgate/Luggage Compartment Lid Ajar Switch

The liftgate/luggage compartment lid ajar switch is integrated into the liftgate/luggage compartment lid latch and not serviceable separately. When the liftgate/luggage compartment lid latch is closed, the liftgate/luggage compartment lid latch ajar switch is closed. When the liftgate/luggage compartment lid latch is opened, the liftgate/luggage compartment lid latch ajar switch is open.

The BCM monitors the liftgate/luggage compartment lid ajar switch input primarily to warn the driver through the message center the liftgate/luggage compartment lid is not closed. When the perimeter alarm detects an unauthorized entry from the liftgate/luggage compartment lid, the alarm activates.

Intrusion Sensor (if equipped)

Some markets are equipped with an intrusion sensor. If equipped, the intrusion sensor is mounted above the front interior lamp.

The BCM monitors input from the intrusion sensor through a LIN circuit. The BCM activates the perimeter alarm if an unauthorized entry is detected from the intrusion sensor.

Anti-Theft Alarm Horn (if equipped)

Some markets are equipped with an anti-theft alarm horn. The anti-theft alarm horn is mounted near the right rear wheel well inside the luggage compartment area.

When the perimeter alarm activates, the BCM provides voltage to the anti-theft alarm horn.

BCM

The BCM controls the operation of the perimeter alarm. The BCM receives inputs from:

• the hood ajar switch
• the door ajar switches
• the driver door arm/disarm switch
• the liftgate/luggage compartment lid ajar switch
• the door lock control switch
• the RKE transmitters
• the PATS
• the passive entry system (if equipped)

Based on the input, the BCM arms, disarms, activates or deactivates the perimeter alarm.

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