See also:

Power Door Locks
On vehicles with power door locks, the switches are located on the front doors. (Unlock): Press to unlock the doors. (Lock): Remove the key from the ignition and press to lock the doors. ...

Diagnostics
OnStar Vehicle Diagnostics will perform a vehicle check every month. It will check the engine, transmission, antilock brakes, and major vehicle systems. It also checks the tire pressures, if the v ...

Automatic Transmission Shift Lock Control Function Check
WARNING 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 aro ...