See also:

Trip Odometer
A trip odometer show how far the vehicle has been driven since the odometer was last set to zero. See Driver Information Center (DIC) for information on resetting the trip odometer. ...

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 ...

Running the Vehicle While Parked
It is better not to park with the engine running. But if you ever have to, here are some things to know. WARNING Idling a vehicle in an enclosed area with poor ventilation is dangerous. Engine ...