Circuit/System Testing

WARNING: This page is about a different car, the 2010 GMC Sierra, 2010 GMC Cab & Chassis Sierra, 2010 Chevrolet Silverado, and 2010 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: You must perform the Circuit/System Verification first.

Ignition ON, clear the DTCs with a scan tool.
Ignition OFF, disconnect the X175 harness connector at the transmission. Verify all vehicle systems are OFF, this may take up to 2 minutes.
Ignition ON, use a scan tool and verify that DTC P0659 or P2671 did not set.
- If DTC P0659 or P2671 did not set, replace the internal transmission wire harness. Refer to Wiring Harness Replacement .
- If DTC P0659 or P2671 sets, test the affected high side driver B+ circuit for a short to voltage. If the circuit tests normal, replace the TCM. Refer to Transmission Control Module Replacement .