Parking Assist Switch: Service and Repair

OPERATION

Each time the park assist switch (also known as the PTS OFF switch) is depressed it provides a signal to the electronic circuitry of the instrument panel switch pod (also known as the Switch Bank Module/SBM or upper control panel/center console switch module/OBF control unit), which the switch pod circuitry reads through an internal pull-up. The switch pod circuitry responds by sending an electronic park assist switch pressed message to the park assist module (also known as the ParkTronic System/PTS module) over the Controller Area Network (CAN) data bus.

The park assist module responds to each park assist switch pressed message by toggling the status of the park assist system from enabled to disabled, or from disabled to enabled, then sends an electronic park assist system status message back to the switch pod over the CAN data bus. The switch pod responds to this status message by toggling a transistor that controls a voltage output to the grounded park assist switch Light Emitting Diode (LED) unit so that the LED is illuminated with the system disabled and the ignition switch in the ON position, and is extinguished with the system enabled or with the ignition switch in any position except ON.

The hard wired circuits between components related to the park assist switch may be diagnosed using conventional diagnostic tools and procedures. However, conventional diagnostic methods will not prove conclusive in the diagnosis of the electronic controls or communication between modules and other devices that provide some features of the park assist system. The most reliable, efficient, and accurate means to diagnose the park assist switch, the CAN data bus or the electronic communication related to park assist switch operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.