WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 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 RPA display.
Ignition ON, verify that a test lamp illuminates between the 12V voltage supply circuit terminal 1 and ground.
- If the test lamp does not illuminate, test the voltage supply circuit terminal for a short to ground or an open/high resistance.
Connect a test lamp between the control circuit and the 12V voltage supply circuit terminal 1 of the appropriate LED listed below:
- Left amber LED control circuit terminal 2
- Center amber LED control circuit terminal 3
- Red LED control circuit terminal 4
Command the appropriate LED ON and OFF with a scan tool, verify that a test lamp turns ON and OFF when switching between commanded states.
- If the test lamp does not illuminate, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the object alarm module.
- If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, test or replace the object alarm module.
If all circuits test normal, test or replace the RPA display.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Circuit/System Testing

Use the Manual With the Right Hardware

When to See a Mechanic