The object alarm detection system senses how close the vehicle is to an object. The distance is determined by the 4 ultrasonic sensors located in the rear bumper. The object detection system will notify the driver when backing up at speeds less than 8 km/h (5 mph), which make parking easier and helps you avoid colliding with objects such as parked vehicles.

Each object sensor is a 3-wire sensor that is both a transmitter and a receiver that comprises a signal circuit, a low reference circuit, and an 8-volt supply voltage circuit. The rear object control module supplies 8 volts to the object sensors via the object sensor supply voltage circuit and provides ground via the low reference circuit. The rear object control module triggers the sensors in a sequential loop and after each sensor transmits, the rear object control module uses the echo or signal return to calculate the distance and position of an object from the rear bumper. The rear object control module directly controls the rear parking assist (RPA) display. The RPA consists of 2 amber and one red LED that indicate the range of an object from the rear bumper. The rear object control module will also use an audible warning by sending a low speed GMLAN message to the radio.

Ignition voltage is between 9-16 volts.

The following condition must exist for 300 milliseconds:

The object alarm module has detected that one of the three indicator control circuits for the rear display is determined to be open or shorted.

Schematic Reference

Object Detection Schematics

Connector End View Reference

Object Detection Connector End Views

Electrical Information Reference

Important: When removing connectors inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector.

1. Ignition ON, use the scan tool and perform the LED Test in Special Functions. The scan tool will command each indicator to turn ON then proceed to the next one. Verify that the information center telltale indicators turn ON.

⇒	If none of the information center telltale indicators turn ON refer to Information Center Telltale Malfunction .

2. Remove the object alarm module connector.
3. The information center telltale does turn ON then remove the rear information center telltale assembly.
4. Test all the indicator circuits between information center telltale assembly indicator connector and the object alarm module for a short to voltage or an open. Verify that a short to voltage or an open does not exist.

⇒	If any of the above conditions are found make the appropriate repair.

5. Reconnect the object alarm module connector.
6. Ignition ON, connect a test lamp between the telltale assembly supply voltage circuit and each indicator control circuit on the information center telltale indicator connector one at a time. With the scan tool perform the LED Test. Verify that each indicator illuminate the test lamp.

⇒	If the test lamp does not illuminate replace the object alarm module.

7. Each indicator illuminate the test lamp then replace the information center telltale assembly replacement (rear). After replacement refer to Repair Verification.

Reconnect all components. Ignition ON, use the scan tool to clear the DTCs then recheck for DTCs. Verify DTC B0968 does not set.