Diagnostic Aids
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.
When attempting to set solenoid electrical DTCs, it may be helpful to ensure the TCM is warmed up and the transmission is operated in second gear long enough to ensure a 3°C (5°F) increase in TCM temperature. This will place the TCM under the optimal conditions to test solenoid electrical DTCs.