Circuit/System Description
WARNING: This page is about a different car, the 2008 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.
Each object sensor is a 3-wire sensor that is both a transmitter and a receiver that includes a signal circuit, a low reference circuit, and an 8-volt supply voltage circuit. The object alarm module supplies 8 volts to the object sensors via the object sensor supply voltage circuit and provides ground via the low reference circuit. The object alarm module triggers the sensors in a sequential loop. After each sensor transmits, the object alarm module uses the echo or signal return to calculate the distance and position of an object from the rear bumper.