Vehicle Theft Security System: Notes

The Vehicle Theft Security System (VTSS) is divided into two basic subsystems: Vehicle Theft Alarm (VTA) and Sentry Key Immobilizer System (SKIS). A Body Control Module (BCM) is used to control and integrate many of the functions and features included in the Vehicle Theft Security System (VTSS). In the VTSS, the BCM receives inputs indicating the status of the door ajar switches, the driver cylinder lock switch, the ignition switch, the liftgate ajar switches, the liftgate flip-up glass ajar switch, the power lock switches and, in vehicles so equipped, the hood ajar switch. The programming in the BCM allows it to process the information from all of these inputs and send control outputs to energize or de-energize the combination flasher, the horn relay (except vehicles with the premium version of the VTA), and the VTSS indicator. In addition, in vehicles built for certain markets where premium versions of the VTA is required, the BCM also exchanges messages with the Intrusion Transceiver Module (ITM) over the Programmable Communications Interface (PCI) data buss network to provide the features found in this version of the VTA. The control of these inputs and outputs are what constitute all of the features of the VTSS.