Circuit/System Testing
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 X2 at the ECM.
- Ignition ON, verify that the wait to start indicator is OFF.
- If not the specified value, test the wait to start indicator control signal circuit terminal 16 for a short to ground. If the circuit tests normal, replace the instrument panel cluster (IPC).
- Install a 3-amp fused jumper between the wait to start control signal circuit terminal 16 and ground. Verify that the wait to start indicator is ON.
- If not the specified value, test the wait to start indicator control signal circuit terminal 16 for a short to voltage or an open/high resistance. If the circuit tests normal, replace the IPC.
- If all circuits test normal, replace the ECM.