GMC Sierra Owners Manual
Starter Switch Check
When you are doing this inspection, the vehicle could move suddenly. If the vehicle moves, you or others could be injured.
1. Before starting this check, be sure there is enough room around the vehicle.
2. Firmly apply both the parking brake and the regular brake.
See Parking Brake on page 9‑58.
Do not use the accelerator pedal, and be ready to turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The vehicle should start only in P (Park) or N (Neutral).
If the vehicle starts in any other position, contact your dealer for service.