Visual/Physical Inspection
WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 2001 GMC Yukon XL, 2001 GMC Yukon, 2001 GMC Sierra, 2001 GMC Cab & Chassis Sierra, and 2001 GMC C3500 HD. However, it is still accessible from the selected car via links, so may be relevant.
- Inspect for aftermarket devices which could affect the operation of the automatic transmission shift lock control system. Refer to Checking Aftermarket Accessories in Wiring Systems.
- Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.