Interior Backlighting Malfunction
WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the harness connector at the appropriate component.
- Verify that a test lamp illuminates between the listed ground circuit terminal and B+.
- Rear Window Switch terminal F
- Headlamp and Panel Dimmer Switch terminal 8
- Transfer Case Shift Control Switch terminal 6
- Sunroof Switch terminal 5
- Roof Beacon Switch terminal 1
- Sliding Rear Window Switch terminal D
- Garage Door Opener Switch terminal 3
- Door Lock Switch terminal B
- Window Switch terminal F
- Outside Rearview Mirror Switch terminal G
- If the test lamp does not illuminate, test the ground circuit for an open/high resistance.
- Connect a test lamp between the listed backlighting control circuit terminal and ground.
- Rear window switch terminal B
- Headlamp switch terminal 7
- Transfer case control switch terminal 5
- Sunroof switch terminal 3
- Roof beacon switch terminal 2
- Sliding rear window switch terminal E
- Garage door opener switch terminal 2
- Door Lock Switch terminal A
- Window Switch terminal B
- Outside Rearview Mirror Switch terminal E
- Command the Incandescent Dimming Test ON with a scan tool. The test lamp should turn from bright to dim when changing between the commanded states.
- If the test lamp is always off, 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 is always bright, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
- If all circuits test normal, test or replace the appropriate component.