Intrusion Sensor: Operation: Receiver

The intrusion sensor receiver operates only when it is energized by the intrusion module. The receiver monitors ultrasonic signals generated in the vehicle cabin by the intrusion sensor transmitter through a receive transducer. The receiver listens to the ultrasonic signals as they bounce off of objects in the vehicle interior and provides input signals to the intrusion module. If an object is moving in the interior, a detection circuit in the intrusion module senses this movement through the modulation of the returning signals that occur due to the Doppler effect. The intrusion module monitors the current draw of the receiver circuits to determine the condition of the receiver and, if the draw is too high or too low, it will store a Diagnostic Trouble Code (DTC) for any fault that is detected.

The hard wired circuits for the receiver may be diagnosed and tested using conventional diagnostic tools and procedures. However, conventional diagnostic methods will not prove conclusive in the diagnosis of the intrusion module, the Controller Area Network (CAN) data bus, or the electronic message inputs to and outputs from the intrusion module. The most reliable, efficient, and accurate means to diagnose the intrusion sensor receiver, the intrusion module, the CAN data bus and the message inputs to and outputs from the intrusion module requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.