FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Principles of Operation (How Does It Work?)

PRINCIPLES OF OPERATION

The parking aid system detects objects behind the vehicle when the vehicle is in reverse gear. The parking aid module does this by calculating the distance to an object by the use of four ultrasonic sensors mounted in the rear bumper. The ultrasonic field is emitted in a semicircular area around the rear of the vehicle. The parking aid sensors can detect objects approximately 1.8 m (5.9 ft) to the rear of the vehicle, 50 cm (1.6 ft) to the rear side of the vehicle, and 16 cm (6 in) above ground. A 750 Hz variable warning tone is generated from a parking aid speaker attached to the parking aid module. The parking aid speaker increases its warning tone rate as the vehicle gets closer to 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 key is in RUN and reverse (R) gear is selected. The system can be disabled through the message center located in the instrument cluster.

The parking aid system will be disabled if a fault is detected in one of the four sensors, the parking aid speaker or the parking aid module. This will be indicated by the parking aid disabled warning. The parking aid module is on the International Standards Organization (ISO) 9141 network and can be diagnosed with a diagnostic tool.