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Principles of Operation

PRINCIPLES OF OPERATION

The parking aid system detects objects behind the vehicle when the vehicle is in REVERSE. The parking aid module does this by calculating the distance to an object using 4 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 (6 feet) to the rear of the vehicle, 50 cm (1.6 feet) to the rear side of the vehicle, and 16 cm (6 inches) 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 20 cm (8 inches) of the sensors, the warning tone becomes continuous.

The parking aid system is enabled when the ignition switch is in RUN or START position and when REVERSE is selected. The system can be disabled through the parking aid disable switch.

The parking aid module will prove out the indicator, located in the parking aid disable switch, by constantly illuminating the indicator for 3 seconds. If the parking aid module detects a failure it constantly illuminates the indicator for as long as the failure condition exists and the ignition switch is in the RUN position. The parking aid module is on the International Standards Organization (ISO) 9141 network and can be diagnosed with a diagnostic tool.