See also:

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 ...

Global Positioning System (GPS)
The navigation system determines the position of the vehicle by using satellite signals, various vehicle signals, and map data. At times, other interferences such as the satellite condition, road c ...

Sun Visors
Pull the sun visor down to block glare. Detach the sun visor from the center mount to pivot to the side window, or to extend along the rod, if available. ...