See also:

Electronic Transfer Case
The transfer case knob is located next to the steering column. Use the dial to shift into and out of four-wheel drive. ...

Battery
The battery supplies power to start the engine and operate any additional electrical accessories. • To avoid break-down or failure to start the vehicle, maintain a battery with full cranking power. ...

How OnStar Service Works
Automatic Crash Response, Emergency Services, Crisis Assist, Stolen Vehicle Assistance, Vehicle Diagnostics, Remote Door Unlock, Roadside Assistance, Turn-by-Turn Navigation, and Hands-Free Callin ...