Circuit/System Testing
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2012 GMC Yukon XL, 2012 GMC Yukon, 2012 Chevrolet Tahoe, 2012 Chevrolet Suburban, and 2012 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the X4 harness connector at the BCM.
- Ignition ON, verify the windshield washer pump is not on.
- If the windshield washer pump is on, test the windshield washer pump relay control circuit terminal 15 for a short to ground. If the circuit tests normal replace the underhood fuse block.
- Install a 10A fused jumper wire between the relay control circuit terminal 15 and ground. Verify the windshield washer pump is on.
- If the windshield washer pump is not on, test the relay control circuit for a short to voltage or an open/high resistance. If the circuit tests normal replace the underhood fuse block.
- If all circuits test normal, replace the BCM.