Anti-Theft - Perimeter

Anti-Theft

Principles of Operation

The Body Control Module (BCM) controls the operation of the perimeter alarm based on the following inputs:

- door ajar switches

- hood ajar

- driver door lock cylinder

- door lock control switch

- Passive Anti-Theft System (PATS) input

- and the Remote Keyless Entry (RKE) transmitters

On vehicles equipped with Intelligent Access (IA) the BCM (Body Control Module) receives the RKE (Remote Keyless Entry) transmitter and IA (Intelligent Access) input from the Remote Function Actuator (RFA) module over the Medium Speed Controller Area Network (MS-CAN). If the perimeter alarm is armed, and the BCM (Body Control Module) receives an input indicating an unauthorized entry into the vehicle or the ignition is turned to the RUN position without a programmed PATS (Passive Anti-Theft System) key, the BCM (Body Control Module) activates the perimeter alarm. When the perimeter alarm is activated, the anti-theft horn sounds and the turn signals flash in regular intervals. The traffic horn does not sound during a perimeter alarm event.

Battery Disconnect

If the battery is disconnected and then reconnected, the perimeter alarm remains in the same state (disarmed, pre-armed, armed, or activated) it was prior to the battery disconnect.

Alarm Event PIDs

The BCM (Body Control Module) has PIDs available that show what caused the last alarm events. The 5 BCM (Body Control Module) alarm event PIDs are ALARM_1 through 5. The cause for the most recent alarm activation is always listed in the first alarm event PID. These PIDs display what caused the alarm to activate and can be a very useful tool when trying to identify the cause of a false alarm activation.