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.

IMPORTANT: Any DTCs set, even those not listed in the I/M system DTC table, may prevent the required DTCs from running.

Repair any DTCs or driveability concerns.
Review any service bulletins for software updates that may prevent the required DTCs from running.
Perform any reprogramming or repairs indicated by the service bulletins.
- If more than one system indicates a NO status or did not update to YES, refer to Inspection/Maintenance (I/M) Complete System Set Procedure .