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 turn signal/multifunction switch.
- Test for less than 1 ohm of resistance between the ground circuit terminal D and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
- Ignition ON, verify the scan tool Flash to Pass Switch parameter is Inactive.
- If not the specified value, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the BCM.
- Install a 3A fused jumper wire between the signal circuit terminal A and the ground circuit terminal D. Verify the scan tool Flash to Pass 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 BCM.
- If all circuits test normal, test or replace the signal/multifunction switch.