Intrusion Transceiver Module

An Intrusion Transceiver Module (ITM) is part of the premium version of the Vehicle Theft Alarm (VTA) in the Vehicle Theft Security System (VTSS). The premium version of the VTA is only available in vehicles built for certain markets, where the additional features offered by this system are required. The ITM is located in the passenger compartment. This unit is designed to provide interior motion detection, and serve as an interface between the Body Control Module (BCM) and the alarm siren module. The ITM is concealed beneath a dedicated molded plastic trim cover that approximates the size and shape of a typical dome lamp housing. However, rather than a lens, the ITM features three sets of louvered openings. One set of louvered openings is located at each outboard end of the center rib, while the third set is centered. Each of the louvered openings is covered on the inside by a sight shield that extends the length of the center rib. The module is secured to a mounting bracket above the headliner. Concealed within the housing is the circuitry of the ITM which includes a microprocessor and an ultrasonic receive transducer. Both the transmit transducer on the right side of the module and the receive transducer on the ITM circuit board are aimed through two small round holes in the sight shield of the trim cover. The ITM is connected to the vehicle electrical system by a take out and connector of the overhead wire harness that is integral to the headliner. The ITM unit cannot be adjusted or repaired and if faulty or damaged, it must be replaced. The ITM is serviced as a unit with the trim cover.