Park Assist System

Fig 1: Park Assist System

Courtesy of DAIMLERCHRYSLER CORP.

The Park Assist System is an electronic parking aid that alerts the driver to obstacles which are located immediately behind the vehicle. Objects are sensed using ultrasonic sound waves. When an object is detected, the system will give the driver visual and audible warnings. The system can be turned OFF and ON with a disable switch located in the upper instrument panel switch pod, in the instrument panel center stack, just above the radio. The system is enabled from the factory as a default.

The major components of the park assist system are:

• Park Assist Module (3)  - supplies voltage to the object detection sensors and park assist display. It triggers the sensors, analyzes the echo delay times and calculates obstacle distances. It sends display information to the park assist display, performs system diagnostics, and communicates via the Controller Area Network (CAN) date bus network.
• Park Assist Sensors (5)  - there are four sensors located in the rear bumper that generate ultrasonic pulses when triggered by the park assist module. The sensors signal the park assist module when reflected ultrasonic pulses are received.
• Park Assist Display (4)  - there are sixteen Light Emitting Diode (LED) indicators which provide indication of relative distance to obstacles. When the system is engaged and no obstacles are detected, the two outermost yellow LED's are lit at reduced brightness to show the system is working. As the distance to a detected obstacle decreases, more yellow LED's towards the center of the display illuminate.
• Park Assist OFF Switch (2)  - this is so the park assist system can be disabled/enabled if the system is not desired (I.E. during off road use where large objects are common). When the system is disabled, the EVIC display in the EMIC (1) will display "Park Assist Disabled".

For diagnosis and testing of the park assist system, use a scan tool and the appropriate body diagnostic information.