Parking Aid System Operation

The PAM calculates and reports via audio tones the distance to an object within a 170 degree semicircular area (azimuth) around the rear of the vehicle. When the system is active and an object is detected within the parking aid azimuth around the rear of the vehicle, the PAM sounds a variable rate warning tone through the rear parking aid speaker.

The rear parking aid system is active only when the transmission selector lever is in reverse. To determine the selector lever position, the PAM receives the transmission gear lever position message on the HS-CAN from the PCM (gasoline vehicles) or TCM (diesel vehicles). There is a brief time delay between reverse gear selection and activation of the rear parking aid to prevent unintended activation when the selector lever is moving from park to drive.

When the rear parking aid system is active, the PAM calculates the distance to an object around the rear of the vehicle using 4 ultrasonic sensors. The parking aid sensors detect objects approximately 1, 800 mm (71 in) from the rear of the vehicle, 610 mm (24 in) from the rear side of the vehicle, and 305 mm (12 in) above the ground. To detect objects behind the vehicle, the PAM supplies voltage and ground to the rear ultrasonic sensors while monitoring a signal return circuit from each sensor. The 4 rear sensors share common voltage supply and ground circuits.

The parking aid can be disabled at any time by pressing the parking aid switch. The system remains disabled until the switch is pressed again or the ignition is turned off and back on. When the parking aid is disabled using the parking aid switch, the PAM supplies voltage to illuminate the parking aid switch LED. When a MyKey® restricted key is in use, the rear parking aid can not be disabled.

Only objects that reflect a sufficient amount of sound waves are detected by the rear parking aid sensors. The surface properties, size, and composition of an object can affect the ability of the parking aid system to detect the object. Incorrect sensor alignment or installation, dirt or ice covered sensors, heavy rain and snow can also cause objects not to be detected.

Parking Aid Audible Alert 

When reverse gear is selected and an object has been detected by the rear parking aid sensors, the PAM sounds a variable rate warning tone through the rear parking aid speaker. As the vehicle approaches the object the warning tone rate increases in frequency, becoming continuous when the vehicle is approximately 305 mm (12 in) from the object. If an object is detected within 305 mm (12 in) of the rear side of the vehicle as it's stationary or moving away, the continuous tone is only generated for 3 seconds.