Principles of Operation

The parking aid sensors detect objects approximately 1.6 m (5.3 ft) from the rear of the vehicle, 50 cm (1.6 ft) from the rear side of the vehicle, and 16 cm (6 in) above the ground. The Parking Aid Module (PAM) calculates the distance to an object within the 170 degree semicircular area around the rear of the vehicle. A variable rate warning tone is generated from a parking aid speaker which is integral to the PAM  . The parking aid speaker increases the warning tone rate as the vehicle gets nears an obstacle. When an object is detected within 25 cm (10 in) of the sensors, the warning tone becomes continuous.

The parking aid system is enabled when the ignition switch is in the RUN position and the REVERSE (R) gear is selected. The parking aid system is disabled if a fault is detected in 1 of the 4 sensors, the parking aid speaker or the PAM  . This condition is indicated by the parking aid disabled warning in the message center. The PAM  communicates on the MS-CAN  and can be diagnosed with a scan tool.

The PAM  communicates with the scan tool, the SJB  , the Audio Control Module (ACM) and the IC  on the MS-CAN. The following chart describes network messages used by the PAM  :