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For 1990-2009 cars only

Rear Vision Camera System Malfunction with UVC

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit/System Description

When the transmission is placed into REVERSE, a 12 volt signal is sent to the rearview camera image display module indicating that camera operation is requested. The rearview camera image display module then supplies ignition voltage and ground to the rear vision camera. The rear vision camera sends video information through the rearview camera image display module 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.

Diagnostic Aids

    • An inoperative rear vision camera system or rear camera symbols not appearing on the display may be due to customer selectable settings being turned off. For normal operating characteristics of the rear vision camera system, refer to the Rear Vision Camera section in the Navigation System supplement of the owners manual.
    • 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.

Reference Information

Schematic Reference

Object Detection Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Object Detection Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Inspect the rearview camera and verify there are no debris on the lens or that the bezel or bezel seal is not damaged.
  2. If debris are found on the lens, clean the lens. If the lens, bezel, or bezel seal are damaged, replace as necessary.
  3. Ignition ON, vehicle in PARK, verify the backup lamps are off.
  4. If the backup lamps are illuminated, refer to Rear Vision Camera System Always On.
  5. Vehicle in REVERSE, verify a clear rear vision image is displayed on the radio.
  6. If a clear image is not displayed, refer to Rear Vision Camera System Does Not Display.

Circuit/System Testing

Rear Vision Camera System Always On

  1. Ignition OFF, disconnect the harness connector at the rear view camera image display module.
  2. Ignition ON, vehicle in PARK, verify a test lamp does not illuminate between the control circuit terminal 1 and ground.
  3. If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit test normal, refer to.
  4. If all circuits test normal, replace the rearview camera image display module.

Rear Vision Camera System Does Not Display

  1. Ignition OFF, disconnect the harness connector at the rear view camera image display module.
  2. Test for less than 1.0 ohm between the ground circuit terminal 3 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 2 and ground.
  5. If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
  6. Ignition ON, park brake applied, vehicle in REVERSE, verify that a test lamp illuminates between the control circuit terminal 1 and ground.
  7. 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.
  8. Ignition OFF, connect the harness connector at the rear view camera image display module. Disconnect the harness connector at the rearview camera.
  9. Ignition OFF, test for less than 1.0 ohm between the ground circuit terminal B and ground.
  10. If greater than the specified range, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the rear view camera image display module.
  11. Ignition ON, park brake applied, vehicle in REVERSE, test for 5.8-6.2 volts between the 6-volt reference circuit terminal A and ground.
  12. If less than the specified range, test the 6-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the rear view camera image display module.
    If greater than the specified range, test the 6-volt reference circuit for a short to voltage. If the circuit tests normal, replace the rear view camera image display module.
  13. Ignition OFF, disconnect the harness connector at the rear view camera image display module.
  14. Test for less then 1 ohm between the shield ground circuit terminal 10 at the rear vision camera display module harness connector and terminal D at the rear vision camera harness connector.
  15. If greater than the specified range, test the shield ground circuit for an open/high resistance.
  16. Ignition ON, test for less than 1 volt between the signal circuit terminal 9 and ground.
  17. If greater than the specified range, test the signal circuit for a short to voltage.
  18. Test for infinite resistance between the signal circuit terminal 9 and ground.
  19. If not the specified value, test the signal circuit for a short to ground.
  20. Test for less then 1 ohm between the signal circuit terminal 9 at the rear vision camera display module harness connector and terminal C at the rear vision camera harness connector.
  21. If greater than the specified range, test the signal circuit for an open/high resistance.
  22. Ignition OFF, disconnect the X4 harness connector at the radio.
  23. Ignition ON, test for less than 1 volt between the following signal circuits at the radio harness connector X4 and ground:
  24. • Video + signal circuit terminal 6
    • Video - signal circuit terminal 7
  25. Test for infinite resistance between the following signal circuits at the radio harness connector X4 and ground:
  26. If greater than the specified range, test the signal circuit for a short to voltage.
    • Video + signal circuit terminal 6
    • Video - signal circuit terminal 7
    If greater than the specified value, test the signal circuit for a short to ground.
  27. Test for less then 1 ohm between the following signal circuits:
  28. • Signal circuit terminal 12 at the rearview camera image module and terminal 6 at the radio.
    • Signal circuit terminal 11 at the rearview camera image module and terminal 7 at the radio.
    If greater than the specified range, test the signal circuit for an open/high resistance.
  29. If all circuits test normal, test or replace the rear vision camera.
  30. Ignition ON, park brake applied, vehicle in REVERSE, verify a clear rear vision image is displayed on the radio.
  31. If a clear rear vision image is not displayed, test or replace the radio.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Rearview Camera Image Display Module Replacement
    •  Rearview Camera Replacement