Module, Park Assist (PAM): Operation

WARNING: This page is about a different car, the 2020 Dodge Challenger. However, it is still accessible from the selected car via links, so may be relevant.

The microcontroller within the Park Assist Module (PAM) contains the park assist system logic circuits. The PAM uses On-Board Diagnostics (OBD) and can communicate with other Electronic Control Units (ECUs) in the vehicle as well as with the diagnostic scan tool using the Controller Area Network (CAN) data bus. This method of communication is also used for park assist system diagnosis and testing through the 16-way Data Link Connector (DLC) located on the driver side lower edge of the instrument panel.

The PAM provides source current to the four park assist sensors located on the back of the rear bumper fascia. The PAM then monitors return inputs from each of the sensors on dedicated hardwired data communication circuits. These sensor inputs allow the PAM to determine when an obstacle is in the rear path of the vehicle, to calculate the relative location of the obstacle and to determine whether the distance to that obstacle is increasing or decreasing.

Pre-programmed decision algorithms and calibrations allow the PAM to determine the appropriate park assist system outputs based upon the inputs received from the park assist sensors and electronic messages received from other ECUs in the vehicle over the CAN data bus. When the programmed conditions are met, the PAM sends electronic messages to the Instrument Panel Cluster (IPC) and the radio over the CAN data bus to obtain the proper park assist system visual and audible outputs.

The PAM continuously monitors all of the park assist system electrical circuits and components to determine the system readiness. If a monitored system fault is detected, the PAM sets a Diagnostic Trouble Code (DTC) and sends the appropriate electronic messages to the IPC to control the display of the appropriate park assist system graphics and textual messages in the Electronic Vehicle Information Center (EVIC) display within the IPC and the generation of the appropriate audible warnings by the radio.

The PAM receives battery current on a fused ignition output (run) circuit through the Body Control Module (BCM). The PAM has a path to ground at all times through a ground circuit and take out of the body wire harness that is secured to the body sheet metal. These connections allow the PAM to be operational whenever the status of the ignition is ON.