The body control module (PZM) controls all of the alarm functions. When the PZM detects an unauthorized entry, the PZM applies ground to the following components:

The PZM applies ground once per second for approximately 3 minutes, or until a valid input to disarm the system is received by the PZM.

The theft deterrent system uses the door ajar switches in the door lock assembly as one method in order to activate the alarm. The body control module (PZM) monitors the door ajar switches input. The alarm mode activates when both of the following conditions are met:

A loose or corroded door ajar switch connector may activate the system intermittently. Inspect the door ajar switch connectors for proper connection. Repair or replace the switch as needed.

The rear compartment lid is equipped with a lock cylinder tamper switch. Any movement of the lock cylinder activates the tamper switch. Both or either of the following actions activate the lock cylinder tamper switch:

The following conditions may activate the system intermittently:

The front door lock cylinders are equipped with switches in order to disarm the theft deterrent system. When the lock cylinder is turned in order to unlock the door, the switch grounds the disarm input to the body control module (PZM). Service the switch separately from the lock cylinder.

The remote function actuator (RFA) system may also arm and disarm the content theft deterrent (CTD) system. When the RFA module receives a door lock or unlock signal from the key fob, the RFA module sends a message to the body control module (PZM) in order to perform the appropriate door lock/unlock command. This action is done via the class 2 serial data line. The PZM detects the message, then performs one of the following functions: