Circuit/System Verification

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

Verify that DTCs P0721, P0722, P0723, P0756, P0757, P0796, P0797, P0966, P0967, P0969, P0970, P0971, P0973, P0974, P0976, P0977, P2720, P2721, P2728, P2729, P2730, P2797, or P0C2B is not set.
- If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle .
Perform the Transmission Fluid Level and Condition Check to verify correct fluid level and condition.
Verify using Freeze Frame and Failure Records, the Aux. Trans. Fluid Pump Actual parameter is within 25 percent of the Aux. Trans. Fluid Pump Commanded parameter.
- If the Aux. Trans. Fluid Pump Actual parameter is not within 25 percent of the Aux. Trans. Fluid Pump Commanded parameter, refer to Auxiliary Fluid Pump Pressure High or Low .
Perform the Line Pressure Check to verify correct oil pressure.
Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection to verify control solenoid valve assembly condition.
Perform the Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test to verify control solenoid valve assembly function.
Inspect the trans fluid pump ball check valve for possible sticking or damage.
- If you found a concern with the check ball, repair the concern.
Inspect the hybrid low, 1-2 clutch regulator valve for sticking or damage.
- If you found a concern with the hybrid low, 1-2 clutch regulator valve, repair or replace the valve or valve body.
Inspect the hybrid low, 1-2 clutch assembly for wear or damage.
- If you found a hybrid low, 1-2 clutch assembly concern, repair or replace the low and reverse clutch assembly as necessary.