Circuit/System Testing
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2008 GMC Yukon XL, 2008 GMC Yukon, 2008 Chevrolet Tahoe, 2008 Chevrolet Suburban, and 2008 Cadillac Escalade EXT. However, it is still accessible from the selected car via links, so may be relevant.
- Ensure the TFT is near the temperature displayed in the Failure Records.
- Start the engine and observe the TFP Switch 1 parameter while moving the range selector lever from Park to Reverse. The TFP Switch 1 should transition from Hi in Park to Low in Reverse.
- If the TFP Switch 1 parameter does not change, perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection .
- If no concerns are found, replace the control solenoid valve and TCM assembly.