Object Detection System - Park Assist System GMC Sierra 2500

Scheme 1

Scheme 2

Scheme 3

Scheme 4

Scheme 5

Diagnostic Code Index

DIAGNOSTIC CODE INDEX

Diagnostic Instructions

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

Circuit/System Description

The body control module (BCM) supplies B+ to the rearview camera when the transmission is placed into reverse.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts

Conditions for Setting the DTC

The BCM detects there is a short to ground or an open circuit.

Action Taken When the DTC Sets

Rearview camera is disabled.

Conditions for Clearing

1. The DTC will transition to history when the fault is no longer present.
2. A history DTC will clear after 100 malfunction-free ignition cycles.

Reference Information

Schematic Reference

Object Detection Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

Object Detection Description and Operation (UVC) , Object Detection Description and Operation (UD7)

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the rearview camera.
2. Ignition ON, park brake applied, transmission in REVERSE, test for B+ between the B+ circuit terminal 3 and ground. If less than the specified value, test the B+ circuit for a short to ground or an open/high resistance.
3. If all circuits test normal, replace the BCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using the diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

Diagnostic Fault Information

The object alarm sensors are 3-wire sensors that are used to determine the distance between the vehicle and an object of interest. The rear object sensor control module supplies 8 V to the object alarm sensors via the 8 V reference circuit and provides ground via the low reference circuit. The rear object sensor control module triggers the sensors in a sequential loop. After each sensor transmits, the rear object sensor control module uses the sensor echo received through the signal circuit to calculate the distance and position of an object.

1. DTC B1325 is not set
2. Ignition voltage is between 9-16 V
3. Transmission in REVERSE

B0958 01, B0959 01, B0960 01, or B0961 01

Voltage seen on the object alarm sensor signal circuit is greater than 11.5 V or the object alarm sensor is not grounded.

B0958 06, B0959 06, B0960 06, or B0961 06

Voltage seen on the object alarm sensor signal circuit is less than 0.5 V.

B0958 08, B0959 08, B0960 08, or B0961 08

An invalid signal is received by the rear object sensor control module.

B0958 3A, B0959 3A, B0960 3A, B0961 3A

The rear object sensor control module determines there is an incorrect sensor installed.

1. The parking assist system is disabled.
2. The rear object sensor control module sends a serial data message to the instrument panel cluster (IPC) to display SERVICE PARK ASSIST message in the driver information center (DIC).

Conditions for Clearing the DTC

1. The DTC will transition to history when the fault is no longer present.
2. A history DTC will clear after 100 malfunction-free ignition cycles.

Diagnostic Aids

Make sure the object alarm sensors located on the rear vehicle bumper are clear. Remove any snow, mud or ice that is blocking the sensors.

Schematic Reference

Object Detection Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

Object Detection Description and Operation (UVC) , Object Detection Description and Operation (UD7)

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
3. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)
4. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Verify that DTC B1405 is not set. If DTC is set, refer to «DTC B1405»(/gmc/sierra-2500/2012-2012/remont/collisionavoidance/#object-detection-system-park-assist-system) .
2. Verify that DTC B0958 3A, B0959 3A, B0960 3A, or B0961 3A is not set. If DTC is set, replace the appropriate object alarm sensor.

Single Object Alarm Sensor DTC Set

1. Ignition OFF, disconnect the harness connector at the appropriate object alarm sensor.
2. Ignition OFF for 30 seconds, test for less than 20 ohms between the low reference circuit terminal 2 and ground. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the rear object sensor control module.
3. Ignition ON, transmission in REVERSE, test for 8.0-9.0 V between the voltage reference circuit terminal 1 and ground. If greater than the specified range, test the voltage reference circuit for a short to voltage. If the circuit tests normal, replace the rear object sensor control module. If less than the specified range, test the voltage reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the rear object sensor control module.
4. Ignition OFF, remove the malfunctioning object alarm sensor and swap locations with another properly functioning object alarm sensor.
5. Connect the harness connector at both sensors.
6. Ignition ON, verify DTC is set for the new location in which the malfunctioning object alarm sensor is installed. If the DTC does not set for the new location, test the signal circuit terminal 3 for a short to voltage, short to ground, or an open/high resistance. If the circuit tests normal, replace the rear object sensor control module.
7. If the DTC sets for the new location in which the malfunctioning object alarm sensor is installed, replace the appropriate object alarm sensor.

Multiple Object Alarm Sensor DTCs Set

1. Ignition OFF, disconnect the harness connector at each of the object alarm sensors.
2. Ignition OFF for 30 seconds, test for less than 20 ohms between the low reference circuit terminal 2 and ground. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the rear object sensor control module.
3. Ignition ON, transmission in REVERSE, test for 8.0-9.0 V between the voltage reference circuit terminal 1 and ground. If greater than the specified range, test the voltage reference circuit for a short to voltage. If the circuit tests normal, replace the rear object sensor control module. If less than the specified range, test the voltage reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the rear object sensor control module.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Rear Parking Assist Alarm Sensor Replacement»(/gmc/sierra-2500/2012-2012/remont/collisionavoidance/#object-detection-system-park-assist-system)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for object alarm module replacement, programming and setup

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The parking assist system can be disabled by pressing the parking assist disable switch. When pressed, the parking assist disable signal circuit is pulled to ground. When the parking assist system is disabled, the rear object sensor control module will ground the parking assist disable indicator control circuit, illuminating the indicator.

1. DTC B1325 is not set
2. Ignition voltage is between 9-16 volts.

The rear object sensor control module has detected that the parking assist disable switch signal circuit is shorted to ground.

1. The parking assist system is disabled.
2. The parking assist disable indicator is not illuminated.
3. The rear object sensor control module sends a serial data message to the instrument panel cluster (IPC) to display SERVICE PARK ASSIST message in the driver information center (DIC).

1. The DTC will transition to history when the fault is no longer present.
2. A history DTC will clear after 100 malfunction-free ignition cycles.

If the parking aid switch is continuously pressed for greater than 5 seconds the DTC will set.

Schematic Reference

Object Detection Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

Object Detection Description and Operation (UVC) , Object Detection Description and Operation (UD7)

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the scan tool Park Assist Switch parameter while cycling the parking assist disable switch. The parameter should change between Active and Inactive.

1. Ignition OFF, disconnect the harness connector at the I/P multifunction switch.
2. Test for less than 1.0 ohms between the ground circuit terminal 3 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify that the scan tool Park Assist Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the rear object sensor control module.
4. Ignition OFF, connect a 3A fused jumper wire between signal circuit terminal 2 and ground.
5. Ignition ON, verify that the scan tool Park Assist Switch parameter is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the rear object sensor control module.
6. If all circuits test normal, test or replace the I/P multifunction switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Accessory Switch Replacement (without RPO SLT)»(/gmc/sierra-2500/2012-2012/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges) , «Accessory Switch Replacement (with RPO SLT)»(/gmc/sierra-2500/2012-2012/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for Object Alarm Module replacement, setup, and programming.

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The parking assist system can be disabled by pressing the parking assist disable switch. When the parking assist system is disabled the rear object sensor control module will ground the parking assist disable indicator control circuit, illuminating the indicator.

1. DTC B1325 is not set
2. Ignition voltage is between 9-16 V

The rear object sensor control module detects the parking assist disable indicator control circuit is shorted to ground, shorted to voltage or open.

1. The parking assist system is disabled.
2. The rear object sensor control module sends a serial data message to the instrument panel cluster (IPC) to display SERVICE PARK ASSIST message in the driver information center (DIC).

1. The DTC will transition to history when the fault is no longer present.
2. A history DTC will clear after 100 malfunction-free ignition cycles.

Schematic Reference

Object Detection Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

Object Detection Description and Operation (UVC) , Object Detection Description and Operation (UD7)

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the scan tool Park Assist Switch LED parameter while pressing and releasing the park assist disable switch. The parameter should change between On and Off.

1. Ignition OFF, disconnect the harness connector at the I/P multifunction switch.
2. Ignition ON, verify a test lamp illuminates between the ignition circuit terminal 6 and ground. If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
3. Ignition OFF, connect the harness connector at the I/P multifunction switch. Disconnect the X2 harness connector at the rear object sensor control module.
4. Ignition ON, verify the park assist disable LED is not illuminated. If the LED is illuminated, test the control circuit for a short to ground. If the circuit tests normal, test or replace the I/P multifunction switch.
5. Install a 10 A fused jumper wire between the control circuit terminal 3 and ground. Verify the park assist disable LED is illuminated. If the LED is not illuminated, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the I/P multifunction switch.
6. If all circuits test normal, replace the rear object sensor control module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Accessory Switch Replacement (without RPO SLT)»(/gmc/sierra-2500/2012-2012/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges) , «Accessory Switch Replacement (with RPO SLT)»(/gmc/sierra-2500/2012-2012/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for object alarm module replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When the ignition is turned ON, the rear object sensor control module receives the vehicle identification number (VIN) from the body control module (BCM). The rear object sensor control module will compare the VIN received to the VIN stored in memory.

1. DTC B1325 is not set
2. Ignition voltage is between 9-16 volts

The VIN stored in the rear object sensor control module does not match the received VIN.

1. The parking assist system is disabled.
2. The rear object sensor control module sends a serial data message to the instrument panel cluster (IPC) to display SERVICE PARK ASSIST message in the driver information center (DIC).

1. The DTC will transition to history when the fault is no longer present.
2. A history DTC will clear after 100 malfunction-free ignition cycles.

Schematic Reference

Object Detection Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

Object Detection Description and Operation (UVC) , Object Detection Description and Operation (UD7)

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Verify that DTC B1015 is not set.

1. If the DTC is set, program the rear object sensor control module. If the DTC resets, replace the rear object sensor control module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for Object Alarm Module replacement, setup, and programming.

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The object sensors are 3-wire sensors that are used to determine the distance between the vehicle and an object of interest. The parking assist control module supplies 8 V to the object sensors via the 8 V reference circuit and provides ground via the low reference circuit. The parking assist control module triggers the sensors in a sequential loop. After each sensor transmits, the parking assist control module uses the sensor echo received through the signal circuit to calculate the distance and position of an object.

1. Ignition ON
2. Transmission in REVERSE

B1405 02

The parking assist control module has detected the 8 V reference circuit is shorted to ground.

B1405 03

The parking assist control module has detected the 8 V reference circuit is less than 6.3 V.

B1405 07

The parking assist control module has detected the 8 V reference circuit is greater than 10.4 V.

1. The parking assist is disabled.
2. The driver information center displays SERVICE PARK ASSIST.

The condition for setting the DTC is no longer present.

Schematic Reference

Object Detection Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

Object Detection Description and Operation (UVC) , Object Detection Description and Operation (UD7)

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, transmission in REVERSE, observe the scan tool Sensor Feed Voltage Output parameter. The reading should be between 6.3-10.4 V.

1. Ignition OFF, disconnect the harness connector at each of the object sensors.
2. Ignition ON, transmission in REVERSE, test for 6.3-10.4 V between the 8 V reference circuit terminal 1 at the rear object sensor harness connector and ground. If less than the specified range, test the 8 V reference circuit for a short to ground. If the circuit tests normal, replace the rear object alarm module. If greater than the specified range, test the 8 V reference circuit for a short to voltage. If the circuit tests normal, replace the rear object alarm module.
3. Install each object alarm sensor harness connector one at a time, checking DTCs after each sensor is connected. Verify DTC B1405 is not set as current. If the DTC is set, replace the object alarm sensor that was connected immediately before the DTC set.
4. If all circuits test normal, replace the rear object alarm module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Rear Parking Assist Alarm Sensor Replacement»(/gmc/sierra-2500/2012-2012/remont/collisionavoidance/#object-detection-system-park-assist-system)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for rear object alarm module replacement, setup and programming

Symptoms - Object Detection

Note. Review the system operation in order to familiarize yourself with the system functions. Refer to Object Detection Description and Operation (UVC) , Object Detection Description and Operation (UD7) .

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the system. Refer to «Checking Aftermarket Accessories»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__checking-aftermarket-accessories) .
2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
3. Make sure the object alarm sensors located on the vehicle rear bumper are clear. Remove any snow, mud or ice that is blocking the sensors.
4. Make sure the rear vision camera is clear. Remove any snow, mud or ice that is blocking the rear vision camera.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections .

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom

1. «Parking Assist System Malfunction»(/gmc/sierra-2500/2012-2012/remont/collisionavoidance/#object-detection-system-park-assist-system)
2. «Rear Vision Camera System Malfunction (UVC with Navigational Radio)»(/gmc/sierra-2500/2012-2012/remont/collisionavoidance/#object-detection-system-park-assist-system) , «Rear Vision Camera System Malfunction (SPO without Navigational Radio)»(/gmc/sierra-2500/2012-2012/remont/collisionavoidance/#object-detection-system-park-assist-system) , «Rear Vision Camera System Malfunction (SPO with Navigational Radio)»(/gmc/sierra-2500/2012-2012/remont/collisionavoidance/#object-detection-system-park-assist-system) , «Rear Vision Camera System Malfunction (UVC without Navigational Radio)»(/gmc/sierra-2500/2012-2012/remont/collisionavoidance/#object-detection-system-park-assist-system)

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The parking assist system is designed to identify and notify the driver of an object in the vehicle's path when reversing at speeds of less than 8 km/h (5 mph). The distance and location of the object is determined by four object alarm sensors located in the rear bumper. The parking assist system will notify the driver using an audible signal through the radio speakers.

When the "PARK ASST BLOCKED SEE OWNERS MANUAL" or "PARK ASSIST BLOCKED SEE OWNERS MANUAL" message is displayed in the DIC the disable reason is stored in the Park Assist Disable History.

The scan tool Park Assist Disable History parameters are a list of the seven previous reasons the parking assist system was disabled. These parameters may help in the diagnosis of an intermittent concern or a customer concern which is the result of normal system operation. The following table is a brief description of potential causes and corrective action which may aid in diagnosis

Note. After the detected cause has been addressed the vehicle must be driven at speed greater than 40 km/h (25 mph).

1. Verify the "PARK ASST BLOCKED SEE OWNERS MANUAL" or "PARK ASSIST BLOCKED SEE OWNERS MANUAL" message is not ON for one of the reasons listed in table above. Perform the following steps: If the message is ON and "operating as designed" column is "Yes" per table above The park assist system is functioning correctly and requires no repairs, correct the condition causing the message to be ON and explain normal operation to the customer. If the message is ON and "operating as designed" column is "No" per table above
2. Perform appropriate action listed in the Corrective Action column per the table above. If the message is not ON
3. All OK.

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The parking assist system is designed to identify and notify the driver of an object in the vehicle's path when reversing at speeds of less than 8 km/h (5 mph). The distance and location of the object is determined by four object alarm sensors located in the rear bumper. The parking assist system will notify the driver using an audible signal through the radio speakers.

When the "Park Assist Off", "Park Asst Blocked See Owners Manual", or "Park Assist Blocked See Owners Manual" message is displayed in the DIC the disable reason is stored in the Park Assist Disable History.

The scan tool Park Assist Disable History parameters are a list of the seven previous reasons the parking assist system was disabled. These parameters may help in the diagnosis of an intermittent concern or a customer concern which is the result of normal system operation. The following is a brief description of potential causes which may aid in diagnosis

Park Assist Off

1. Manual Disable - The parking assist system has been disabled by the vehicle operator using the parking assist disable switch.
2. Reverse Overspeed - The vehicle is traveling too fast in reverse at speeds of greater than 8 km/h (5 mph).
3. Inhibit - The rear object sensor control module has lost or received invalid GMLAN signal(s).

Park Asst Blocked See Owners Manual or Park Assist Blocked See Owners Manual

1. Hitch/Object Attached - The rear object sensor control module is detecting an object that is attached to the vehicle or the endgate is lowered. Common items such as a hitch receiver, trailer, object hanging out of endgate, or a bicycle rack may cause this concern. Additionally, damage to the rear of the vehicle or a misaligned sensor may cause this concern. If the vehicle is damaged in a manner that causes the sensor to detect the bumper itself, the rear object sensor control module will interpret this as an attached object and disable the system. Carefully inspect the bumper, bumper mounting surface, and sensor retainers before continuing with normal diagnosis. After the detected cause has been addressed the vehicle must be driven at speed greater than 40 km/h (25 mph).
2. Sensor Disturbance - An outside interference is causing sensor movement. Such interference may be caused by a heavy pounding, like that of a nearby jackhammer, or large changes in pressure, such as a large truck's air brakes.
3. Sensor Ring Time - If the sensor fails its own diagnostic initialization the rear object sensor control module will set this error. After the detected cause has been addressed the vehicle must be driven at speed greater than 40 km/h (25 mph). The following is a list of reasons this cause may have set: One or more of the sensors may be blocked by snow, mud, ice, or other debris. This might happen after going through a car wash in cold weather. Silicone insulator surrounding sensor maybe missing, cut, or twisted. Improperly installed sensor, sensor maybe be crooked due to a tight wire harness. One or more of the sensors may be scratched or the paint maybe chipped. Excessive paint thickness on a sensor may cause an excessive sensor ring time. When replacing or refinishing a sensor, do not apply an excessive amount of paint or clear coat.

Schematic Reference

Object Detection Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

Object Detection Description and Operation (UVC) , Object Detection Description and Operation (UD7)

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON, verify the parking assist system is enabled through the DIC. If the parking assist system is manually disabled, enable the system. Refer to the vehicle owners manual for instructions on enabling the system.
2. Verify Park Assist Blocked See Owners Manual message is not displayed on DIC. If Park Assist Blocked See Owners Manual message is displayed, refer to «Parking Assist System Malfunction»(/gmc/sierra-2500/2012-2012/remont/collisionavoidance/#object-detection-system-park-assist-system) .
3. Observe the scan tool Park Assist Switch parameter while pressing and releasing the park assist disable switch. The parameter should change between Active and Inactive. If the parameter does not cycle between the specified values, refer to Park Assist Disable Switch Circuit Malfunction below.
4. Observe the scan tool Park Assist Switch LED parameter while pressing and releasing the park assist disable switch. The parameter should change between On and Off. If the parameter does not cycle between the specified values, refer to Park Assist Disable LED Circuit Malfunction below.
5. Transmission in REVERSE, verify one audible beep sounds and the scan tool Park Assist System Status parameter is Enable. NOTE: After completing the next step the vehicle might need to be driven in the forward direction at speed greater than 40 km/h (25 mph). If not the specified values, refer to Diagnostic Aids above and the scan tool Park Assist Disable History parameters to determine the cause of the inhibit.

Park Assist Disable Switch Circuit Malfunction

1. Ignition OFF, disconnect the harness connector at the I/P multifunction switch.
2. Test for less than 10 ohms between the ground circuit terminal 3 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool Park Assist Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the rear object sensor control module.
4. Install a 3 A fused jumper wire between the signal circuit terminal 2 and ground. Verify the scan tool Park Assist Switch parameter is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the rear object sensor control module.
5. If all circuits test normal, test or replace the I/P multifunction switch.

Park Assist Disable LED Circuit Malfunction

1. Ignition OFF, disconnect the harness connector at the I/P multifunction switch.
2. Ignition ON, verify a test lamp illuminates between the ignition circuit terminal 6 and ground. If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
3. Ignition OFF, connect the harness connector at the I/P multifunction switch assembly. Disconnect the X2 harness connector at the rear object sensor control module.
4. Ignition ON, verify the park assist disable LED is not illuminate. If the LED is illuminated, test the control circuit for a short to ground. If the circuit tests normal, test or replace the I/P multifunction switch.
5. Install a 10 A fused jumper wire between the control circuit terminal 3 and ground. Verify the park assist disable LED is illuminated. If the LED is not illuminated, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the I/P multifunction switch.
6. If all circuits test normal, replace the rear object sensor control module.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Accessory Switch Replacement (without RPO SLT)»(/gmc/sierra-2500/2012-2012/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges) , «Accessory Switch Replacement (with RPO SLT)»(/gmc/sierra-2500/2012-2012/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for Object Alarm Module replacement, programming and setup

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When the transmission is placed into REVERSE while engine is running, a 12 V signal is sent to the rearview camera indicating that camera operation is requested. Ignition voltage and ground are supplied to the rearview camera. The rearview camera sends video information to the radio through a video signal + and a video signal - circuit. A grounded shielding also wraps the video signal circuits to reduce electronic interference which may degrade the video signal and cause a distorted or otherwise degraded image.

A poor video image can be caused by ice, snow, and mud buildup on the lens of the rearview camera. Also, extreme lighting conditions can affect performance, such as operating in the dark or with bright sunlight shining on the camera. Extreme high or low temperatures can also affect the image quality.

Schematic Reference

Object Detection Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

Object Detection Description and Operation (UVC) , Object Detection Description and Operation (UD7)

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Inspect the rearview camera and verify there is no debris on the lens and that the bezel or bezel seal is not damaged. If debris is found on the lens, clean the lens. If the lens, bezel, or bezel seal are damaged, replace as necessary.
2. Engine running, vehicle in PARK, verify the backup lamps are off. If the backup lamps are illuminated, refer to Rearview Camera System Always On below.
3. Vehicle in REVERSE, engine running, verify backup lamps are on. If the backup lamps are not illuminated, refer to «Backup Lamps Malfunction (Manual Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) , «Backup Lamps Malfunction (Automatic Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) .
4. Vehicle in REVERSE, engine running, verify a clear rear vision image is displayed on the radio. If a clear image is not displayed, refer to Rearview Camera System Does Not Display below.

Rearview Camera System Always On

1. Ignition OFF, disconnect the harness connector X1 at the rearview camera.
2. Ignition ON, vehicle in PARK, verify a test lamp does not illuminate between the control circuit X1 terminal 3 and ground. If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, refer to «Backup Lamps Malfunction (Manual Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) , «Backup Lamps Malfunction (Automatic Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) .
3. If all circuits test normal, test or replace the rearview camera.

Rearview Camera System Does Not Display

1. Ignition OFF, disconnect the harness connectors X1 and X2 at the rearview camera.
2. Test for less than 10 ohms between the ground circuit X1 terminal 2 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
3. Engine running, verify a test lamp illuminates between the ignition circuit X2 terminal 4 and ground. If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
4. Park brake applied, transmission in REVERSE, engine running, verify a test lamp illuminates between control circuit X1 terminal 3 and ground. If test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
5. Ignition OFF, disconnect the X4 harness connector at the radio.
6. Engine running, test for less than 1 V between the following signal circuit terminals at the rearview camera harness connector and ground: Signal (+) circuit X2 terminal 1 Signal (-) circuit X1 terminal 1 If greater than the specified range, test the signal circuit for a short to voltage.
7. Test for infinite resistance between the following circuit terminals at the rearview camera harness connector and ground: Signal (+) circuit X2 terminal 1 Signal (-) circuit X1 terminal 1 If not the specified value, test the circuit for a short to ground.
8. Test for less than 2 ohms between the signal (+) circuit X2 terminal 1 at the rearview camera harness connector and the signal (+) circuit terminal 6 at the radio harness connector If greater than the specified range, test the signal circuit for an open/high resistance.
9. Test for less than 2 ohms between the signal (-) circuit X1 terminal 1 at the rearview camera harness connector and the signal (-) circuit terminal 7 at the radio harness connector. If greater than the specified range, test the signal circuit for an open/high resistance.
10. If all circuits test normal, test or replace the rearview camera.
11. Engine running, transmission in REVERSE, verify a clear rear vision image is displayed on the radio. If a clear rear vision image is not displayed, replace the radio.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Rearview Camera Replacement»(/gmc/sierra-2500/2012-2012/remont/collisionavoidance/#object-detection-system-park-assist-system)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio replacement, programming and setup

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When the transmission is placed into REVERSE while engine is running, a 12 V signal is sent to the rearview camera indicating that camera operation is requested. Ignition voltage and ground are supplied to the rearview camera. The rearview camera sends video information to the radio through a video signal + and a video signal - circuit. A grounded shielding also wraps the video signal circuits to reduce electronic interference which may degrade the video signal and cause a distorted or otherwise degraded image.

A poor video image can be caused by ice, snow, and mud buildup on the lens of the rearview camera. Also, extreme lighting conditions can affect performance, such as operating in the dark or with bright sunlight shining on the camera. Extreme high or low temperatures can also affect the image quality.

Schematic Reference

Object Detection Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

Object Detection Description and Operation (UVC) , Object Detection Description and Operation (UD7)

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Inspect the rearview camera and verify there is no debris on the lens and that the bezel or bezel seal is not damaged. If debris is found on the lens, clean the lens. If the lens, bezel, or bezel seal are damaged, replace as necessary.
2. Engine running, vehicle in PARK, verify the backup lamps are off. If the backup lamps are illuminated, refer to Rearview Camera System Always On below.
3. Vehicle in REVERSE, engine running, verify backup lamps are on. If the backup lamps are not illuminated, refer to «Backup Lamps Malfunction (Manual Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) , «Backup Lamps Malfunction (Automatic Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) .
4. Vehicle in REVERSE, engine running, verify a clear rear vision image is displayed on the radio. If a clear image is not displayed, refer to Rearview Camera System Does Not Display below.

Rearview Camera System Always On

1. Ignition OFF, disconnect the harness connector at the rearview camera.
2. Ignition ON, vehicle in PARK, verify a test lamp does not illuminate between the control circuit terminal 3 and ground. If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, refer to «Backup Lamps Malfunction (Manual Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) , «Backup Lamps Malfunction (Automatic Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) .
3. If all circuits test normal, test or replace the rearview camera.

Rearview Camera System Does Not Display

1. Ignition OFF, disconnect the harness connector at the rearview camera.
2. Test for less than 10 ohms between the ground circuit terminal 5 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
3. Engine running, verify a test lamp illuminates between the ignition circuit terminal 6 and ground. If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
4. Park brake applied, transmission in REVERSE, engine running, verify a test lamp illuminates between control circuit terminal 3 and ground. If test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
5. Ignition OFF, disconnect the X4 harness connector at the radio.
6. Engine running, test for less than 1 V between the following signal circuit terminals at the rearview camera harness connector and ground: Signal (+) circuit terminal 1 Signal (-) circuit terminal 4 If greater than the specified range, test the signal circuit for a short to voltage.
7. Test for infinite resistance between the following circuit terminals at the rearview camera harness connector and ground: Signal (+) circuit terminal 1 Signal (-) circuit terminal 4 If not the specified value, test the circuit for a short to ground.
8. Test for less than 2 ohms between the signal (+) circuit terminal 1 at the rearview camera harness connector and the signal (+) circuit terminal 6 at the radio harness connector If greater than the specified range, test the signal circuit for an open/high resistance.
9. Test for less than 2 ohms between the signal (-) circuit terminal 4 at the rearview camera harness connector and the signal (-) circuit terminal 7 at the radio harness connector. If greater than the specified range, test the signal circuit for an open/high resistance.
10. If all circuits test normal, test or replace the rearview camera.
11. Engine running, transmission in REVERSE, verify a clear rear vision image is displayed on the radio. If a clear rear vision image is not displayed, replace the radio.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Rearview Camera Replacement»(/gmc/sierra-2500/2012-2012/remont/collisionavoidance/#object-detection-system-park-assist-system)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio replacement, programming and setup

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When the transmission is placed into REVERSE while engine is running, a 12 V signal is sent to the inside rearview mirror and rearview camera indicating that camera operation is requested. Ignition voltage and ground are supplied to the rearview camera; the inside rearview mirror is supplied a common ignition voltage and ground source that is shared with other mirror operations. The rearview camera sends video information to the inside rearview mirror through a video signal + and a video signal - circuit. A grounded shielding also wraps the video signal circuits to reduce electronic interference which may degrade the video signal and cause a distorted or otherwise degraded image.

A poor video image can be caused by ice, snow, and mud buildup on the lens of the rearview camera. Also, extreme lighting conditions can affect performance, such as operating in the dark or with bright sunlight shining on the camera. Extreme high or low temperatures can also affect the image quality.

Schematic Reference

Object Detection Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

Object Detection Description and Operation (UVC) , Object Detection Description and Operation (UD7)

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

1. Verify there is no debris on the rearview camera lens. If debris is found on the lens Clean the debris from the lens. If no debris is found on the lens
2. Engine running, transmission in park.
3. Verify the backup lamps are not ON. If the backup lamps are ON Refer to Rearview Camera System Always On below. If the backup lamps are not ON
4. Engine running with the drive wheels chocked, set the park brake and place the transmission in reverse.
5. Verify backup lamps are ON. If the backup lamps are not ON Refer to «Backup Lamps Malfunction (Manual Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) , «Backup Lamps Malfunction (Automatic Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) . If the backup lamps are ON
6. Verify a clear rear vision image is displayed on the inside rearview mirror. If a clear image is not displayed Refer to Rearview Camera System Does Not Display below. If a clear image is displayed
7. All OK.

Rearview Camera System Always On

1. Ignition OFF and all vehicle systems OFF, disconnect the X1 harness connector at the Rearview Camera.
2. Engine running, transmission in park.
3. Verify a test lamp does not illuminate between the control circuit terminal 3 and ground. If the test lamp illuminates Ignition OFF, disconnect the harness connector at the body control module (BCM) and Inside Rearview Mirror, ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage in the circuit. If less than 1 V, refer to «Backup Lamps Malfunction (Manual Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) , «Backup Lamps Malfunction (Automatic Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) . If the test lamp does not illuminate
4. Replace the Rearview Camera.

Rearview Camera System Does Not Display

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the Inside Rearview Mirror. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for less than 5 ohms between the ground circuit terminal 8 and ground. If 5 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 5 ohms
3. Engine running with the drive wheels chocked, set the park brake and place the transmission in reverse.
4. Verify a test lamp illuminates between the control circuit terminal 9 and ground. If the test lamp does not illuminate Ignition OFF, disconnect the X7 harness connector at the BCM and the X1 harness connector at the Rearview Camera Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, refer to «Backup Lamps Malfunction (Manual Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) , «Backup Lamps Malfunction (Automatic Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) . If the test lamp illuminates
5. Ignition OFF, connect a DMM between the signal circuit terminal 6 and the signal circuit terminal 7. Set the DMM to the AC voltage mode and press the Hz button to measure frequency.
6. Engine running with the drive wheels chocked, set the park brake and place the transmission in reverse.
7. Verify the frequency is between 1k-100 kHz. If the frequency is not between 1k-100 kHz Ignition OFF, disconnect the X1 harness connector at the Rearview Camera. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 5 ohms between the ground circuit terminal 2 and ground. If 5 ohms or greater, test the ground circuit for an open/high resistance. If less than 5 ohms Ignition ON. Verify a test lamp illuminates between the ignition circuit terminal 4 and ground. If the test lamp does not illuminate and the circuit fuse is good, test the ignition circuit for an open/high resistance. If the test lamp does not illuminate and the circuit fuse is open, test the ignition circuit for a short to ground. If the circuit tests normal, replace the Rearview Camera. If the test lamp illuminates Engine running with the drive wheels chocked, set the park brake and place the transmission in reverse. Verify a test lamp illuminates between the control circuit terminal 3 and ground. If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM. If the test lamp illuminates. Ignition ON. Test for less than 1 V between the signal circuits listed below and ground. Terminal 1 X2 Terminal 1 X1 If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V. Ignition OFF. Test for infinite resistance between the signal circuits listed below and ground. Terminal 1 X2 Terminal 1 X1 If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance. Test for less than 2 ohms between the terminals listed below. Rearview Camera signal circuit terminal 1 X2 and the Inside Rearview Mirror signal circuit terminal 6 Rearview Camera signal circuit terminal 1 X1 and the Inside Rearview Mirror signal circuit terminal 7 If 2 ohms or greater, repair the open/high resistance on the circuit. If less than 2 ohms. Replace the Rearview Camera. If the frequency is between 1k-100 kHz
8. Connect the harness connector at the Inside Rearview Mirror.
9. Engine running with the drive wheels chocked, set the park brake and place the transmission in reverse.
10. Verify a clear rear vision image is displayed on the Inside Rearview Mirror. If a clear image is not displayed Replace the Inside Rearview Mirror. If a clear image is displayed
11. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Rearview Camera Replacement»(/gmc/sierra-2500/2012-2012/remont/collisionavoidance/#object-detection-system-park-assist-system)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for inside rearview mirror replacement, programming and setup

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When the transmission is placed into REVERSE while engine is running, a 12 V signal is sent to the inside rearview mirror and rearview camera indicating that camera operation is requested. Ignition voltage and ground are supplied to the rearview camera; the inside rearview mirror is supplied a common ignition voltage and ground source that is shared with other mirror operations. The rearview camera sends video information to the inside rearview mirror through a video signal + and a video signal - circuit. A grounded shielding also wraps the video signal circuits to reduce electronic interference which may degrade the video signal and cause a distorted or otherwise degraded image.

A poor video image can be caused by ice, snow, and mud buildup on the lens of the rearview camera. Also, extreme lighting conditions can affect performance, such as operating in the dark or with bright sunlight shining on the camera. Extreme high or low temperatures can also affect the image quality.

Schematic Reference

Object Detection Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

Object Detection Description and Operation (UVC) , Object Detection Description and Operation (UD7)

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

1. Inspect the rearview camera and verify there are no debris on the lens and that the bezel or bezel seal is not damaged. If debris are found on the lens, clean the lens. If the lens, bezel, or bezel seal are damaged, replace as necessary.
2. Engine running, vehicle in PARK, verify the backup lamps are off. If the backup lamps are illuminated, refer to Rearview Camera System Always On below.
3. Vehicle in REVERSE, engine running, verify backup lamps are on. If the backup lamps are not illuminated, refer to «Backup Lamps Malfunction (Manual Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) , «Backup Lamps Malfunction (Automatic Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) .
4. Park brake applied, transmission in REVERSE, engine running, verify a clear rear vision image is displayed on the inside rearview mirror. If a clear image is not displayed, refer to Rearview Camera System Does Not Display below.

Rearview Camera System Always On

1. Ignition OFF, disconnect the harness connector at the rearview camera.
2. Engine running, transmission in PARK, verify a test lamp does not illuminate between the control circuit terminal 3 and ground. If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, refer to «Backup Lamps Malfunction (Manual Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) , «Backup Lamps Malfunction (Automatic Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) .
3. If all circuits test normal, test or replace the rearview camera.

Rearview Camera System Does Not Display

1. Ignition OFF, disconnect the harness connector at the rearview camera.
2. Test for less than 10 ohms between the ground circuit terminal 5 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
3. Engine running, verify a test lamp illuminates between the ignition circuit terminal 6 and ground. If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
4. Park brake applied, transmission in REVERSE, engine running, verify a test lamp illuminates between control circuit terminal 3 and ground. If test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
5. Ignition OFF, disconnect the harness connector at the inside rearview mirror.
6. Test for less than 10 ohms between the ground circuit terminal 8 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
7. Park brake applied, transmission in REVERSE, engine running, test for B+ between the control terminal 9 and ground. If less than the specified value, test the control circuit for an open/high resistance. If the circuit tests normal, refer to «Backup Lamps Malfunction (Manual Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) , «Backup Lamps Malfunction (Automatic Transmission)»(/gmc/sierra-2500/2012-2012/remont/exterior-lights/#lighting-system) .
8. Engine running, test for less than 1 V between the following signal circuit terminals at the rearview camera harness connector and ground: Signal (+) circuit terminal 1 Signal (-) circuit terminal 4 If greater than the specified range, test the signal circuit for a short to voltage.
9. Test for infinite resistance between the following circuit terminals at the rearview camera harness connector and ground: Signal (+) circuit terminal 1 Signal (-) circuit terminal 4 If not the specified value, test the circuit for a short to ground.
10. Test for less than 2 ohms between the signal (+) circuit terminal 1 at the rearview camera harness connector and the signal (+) circuit terminal 6 at the inside rearview mirror harness connector. If greater than the specified range, test the signal circuit for an open/high resistance.
11. Test for less than 2 ohms between the signal (-) circuit terminal 4 at the rearview camera harness connector and the signal (-) circuit terminal 7 at the inside rearview mirror harness connector. If greater than the specified range, test the signal circuit for an open/high resistance.
12. If all circuits test normal, test or replace the rearview camera.
13. Engine running, transmission in REVERSE, verify a clear rear vision image is displayed on the inside rearview mirror. If a clear rear vision image is not displayed, replace the inside rearview mirror.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Rearview Camera Replacement»(/gmc/sierra-2500/2012-2012/remont/collisionavoidance/#object-detection-system-park-assist-system)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for inside rearview mirror replacement, programming and setup

Scheme 6

Rear Object Alarm Control Module Replacement

Scheme 7

Information Center Telltale Assembly Replacement

Removal Procedure

1. Disconnect electrical from the rear object sensor.
2. Lift the locking tabs on the housing and remove the rear object sensor.

Installation Procedure

1. Paint the rear object sensor. Refer to «Basecoat/Clearcoat Paint Systems»(/gmc/sierra-2500/2012-2012/remont/paintcoatings/#paint-and-coatings__basecoatclearcoat-paint-systems) .
2. Ensure the paint does not exceed 6 mils. Use a paint thickness gauge suitable for non-ferrous metals. Refer to «Paint Gauges»(/gmc/sierra-2500/2012-2012/remont/paintcoatings/#paint-and-coatings__paint-gauges) .
3. Insert the sensor into the housing.
4. Connect the electrical connector to the rear object sensor.

Scheme 8

Rear Object Sensor Housing Replacement (Sierra/Silverado)

Rear Object Sensor Housing Replacement (All Other Vehicles)

1. Remove the center rear bumper step pad or the rear bumper impact bar end cap. Refer to «Rear Bumper Step Center Pad Replacement»(/gmc/sierra-2500/2012-2012/remont/exterior-body-panels/#bumpers-and-fascias) , or «Rear Bumper Impact Bar End Cap Replacement»(/gmc/sierra-2500/2012-2012/remont/exterior-body-panels/#bumpers-and-fascias) .
2. Disconnect the sensor harness.
3. Remove the sensor from the sensor housing. The sensor housing must be painted if replaced. If reinstalled, painting will not be necessary.
4. Sand/grind sonic weld plastic residue from the fascia.
5. Apply structural adhesive epoxy, Lord Fusor™ 127EZ or equivalent, to fascia at mating surface.
6. Using the alignment tabs, install the sensor housing to the fascia.
7. Allow adhesive to cure according to manufacturer's directions.
8. Install the sensor to the sensor housing.
9. Connect the electrical harness.
10. Install the center rear bumper step pad or the rear bumper impact bar end cap. Refer to «Rear Bumper Step Center Pad Replacement»(/gmc/sierra-2500/2012-2012/remont/exterior-body-panels/#bumpers-and-fascias) , or «Rear Bumper Impact Bar End Cap Replacement»(/gmc/sierra-2500/2012-2012/remont/exterior-body-panels/#bumpers-and-fascias) .

Scheme 9

Rearview Camera Replacement

Rear Vision Camera System Operation (without UVB)

The components used in the rear vision camera system are the camera, located at the rear of the vehicle, and the inside rearview mirror, which houses the LCD display.

When the vehicle is placed in REVERSE while engine is running, the body control module (BCM) sends a 12 volt signal to the inside rearview mirror and the rearview camera. This signal indicates that rear vision camera operation is required. Upon receipt of this signal, the mirror will begin the power up cycle for the LCD display and the camera will also power up. The rear vision camera transmits the video signal to the inside rearview mirror through discrete + and - signal circuits. A metallic foil encases the video signal circuits and is tied to a shield ground circuit. This shield is designed to reduce electronic interference which may degrade the video signal and cause a distorted or otherwise degraded image.

If desired, the rear vision camera may be manually disabled. Refer to the navigation system owners manual for instructions on manually disabling and enabling the rear vision camera system. The following conditions may cause a degraded rear vision camera image

1. Ice, snow, or mud has built up on the rear vision camera
2. Dark conditions
3. Extreme light conditions, such as glare from the sun or the headlights of another vehicle
4. Damage to the rear of the vehicle
5. Extreme high or low temperatures or extreme temperature changes

Rear Vision Camera System Operation (with UVB)

The components used in the rear vision camera system are the camera, located at the rear of the vehicle, and the navigation radio.

When the vehicle is placed in REVERSE while engine is running, the body control module (BCM) sends a 12 volt signal to the rearview camera. This signal indicates that rear vision camera operation is required. Upon receipt of this signal, the camera will begin the power up cycle. A serial data message is also received by the navigation radio indicating the vehicle is in REVERSE. Upon receipt of this message, the navigation radio will also begin a power up cycle for the display. The rear vision camera transmits the video signal to the navigation radio through discrete + and - signal circuits. A metallic foil encases the video signal circuits and is tied to a shield ground circuit. This shield is designed to reduce electronic interference which may degrade the video signal and cause a distorted or otherwise degraded image.

If desired, the rear vision camera may be manually disabled through the navigation system menu. Refer to the navigation system owners manual for instructions on manually disabling and enabling the rear vision camera system. The following conditions may cause a degraded rear vision camera image

1. Ice, snow, or mud has built up on the rear vision camera
2. Dark conditions
3. Extreme light conditions, such as glare from the sun or the headlights of another vehicle
4. Damage to the rear of the vehicle
5. Extreme high or low temperatures or extreme temperature changes

If a malfunction is detected in the system, Service Rear Vision Camera may be displayed on the navigation radio as an indicator to the customer that a problem exists that requires service.

Object Detection Description and Operation (UD7)

The parking assist system is designed to identify and notify the driver of an object in the vehicle's path when reversing at speeds of less than 8 km/h (5 mph). The distance and location of the object is determined by four object alarm sensors located in the rear bumper. The parking assist system will notify the driver using an audible signal through the radio speakers. The audible signal will vary depending on the distance the object is from the vehicle.

The parking assist system is made up of the following components

1. Rear object sensor control module
2. Object alarm sensors
3. Parking assist disable switch

Rear Object Sensor Control Module

The rear object sensor control module provides an 8 V reference and a low reference to the four object alarm sensors. The rear object sensor control module receives individual signals from each of the four sensors and determines the location and distance of an object based on these inputs. When an object is detected, the rear object sensor control module will send a serial data message to the radio requesting an audible alert.

Object Alarm Sensor

The object alarm sensors are located in the rear bumper of the vehicle. The sensors are used to determine the distance between an object and rear bumper. Each sensor emits an ultrasonic frequency which is reflected off an object located behind the vehicle. These reflections are received by the sensors. The time difference between when the frequency was emitted and when the reflection is received, known as sensor echo, is used to determine the distance to the object. The sensors report this information to the rear object sensor control module.

Rear Parking Assist Operation

When the vehicle is first placed into reverse, an audible beep will sound to indicate the system is working.

When backing up at speed of less than 8 km/h (5 mph), the system is constantly monitoring for object of interest located behind the vehicle. The parking assist system can detect objects greater than 7.6 cm (3 in) wide and 25.4 cm (10 in) tall. The system cannot detect objects below the bumper or underneath the vehicle. If an object is detected within 2.5 m (8 ft) away from the rear bumper, there will be an audible beep out of the speakers. As the vehicle gets closer to an object, the time between the beeps becomes shorter. If the vehicle stops and there is an object within 2.5 m (8 ft) away from the rear bumper the beeping will stop after 5 seconds. When the distance between the object and the vehicle starts to decrease again the beeping will start again.

If the parking assist system detects a malfunction when the vehicle is placed into reverse there will be no audible beep and a DTC will be stored. The rear object sensor control module will send a serial data message to the instrument panel cluster (IPC) to display the SERVICE PARK ASSIST message on the driver information center (DIC).

Rear Parking Assist System DIC Messages

SERVICE PARK ASSIST

The driver information center (DIC) displays SERVICE PARK ASSIST when the rear object sensor control module detects a malfunction in the parking assist system and the system is disabled. The DIC also displays SERVICE PARK ASSIST when a loss of communication occurs with the rear object sensor control module.

PARK ASSIST OFF

The PARK ASSIST OFF message is displayed in the DIC when the parking assist system is disabled manually using the parking assist disable switch.

PARK ASST BLOCKED SEE OWNERS MANUAL

The PARK ASST BLOCKED SEE OWNERS MANUAL message is displayed in the DIC when the parking assist system is disabled due to conditions that disable or inhibit the system.

See also:
• Diagnostic System Check - Vehicle
• Strategy Based Diagnosis
• Diagnostic Procedure Instructions
• WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX
• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs
• Diagnostic Repair Verification
• Control Module References
• Accessory Switch Replacement (without RPO SLT)
• Checking Aftermarket Accessories
• Backup Lamps Malfunction (Manual Transmission)
• Front Seat Replacement - Bucket
• Fastener Caution
• Center Pillar Upper Garnish Molding Replacement
• Basecoat/Clearcoat Paint Systems
• Paint Gauges
• Rear Bumper Step Center Pad Replacement
• Pickup Box Endgate Latch Handle Bezel Replacement (Pickup)
• Endgate Replacement
• DTC B0010
• Object Detection Description and Operation (UD7)