Vehicle Theft Alarm Circuit Operation

CIRCUIT OPERATION
The optional Vehicle Theft Security System (VTSS) is used to protect the vehicle from theft by monitoring the vehicle doors, ignition switch, power door lock circuits, hood, and the liftgate key cylinder to determine if the horn should be sounded and the ignition system disabled.

The Body Control Module (BCM) is used as the control for the system. The inputs for the system are divided in two sections. The front or engine area and the passenger compartment. If there is a malfunction in the engine area switch the system will still ARM but the switch will not be monitored. If the switch becomes functional while the system is ARMED it will be used as an input to the BCM. A problem in any passenger compartment switch will not allow the system to ARM.

The VTSS system uses a lamp located in the message center to indicate when the system is ARMED. The lamp is supplied power on circuit M1. This is the Ignition-Off Draw circuit and is protected by a 10 amp fuse located in cavity 10 of the Power Distribution Center (PDC).

The BCM controls ground for the LED on circuit G69.