See also:

Reactivation for Subsequent Owners
Push and follow the prompts to speak to an Advisor as soon as possible after acquiring the vehicle. The Advisor will update vehicle records and will explain the OnStar service offers and options ...

Transmission Messages
SERVICE 4 WHEEL DRIVE If the vehicle has four-wheel drive, this message may display if a problem occurs with the four-wheel-drive system. If this message appears, stop as soon as possible and turn of ...

Rear Window Defogger
For vehicles with a rear window defogger, a warming grid is used to remove fog from the rear window. (Rear): Press to turn the rear window defogger on or off. An indicator light on the button comes ...