See also:

Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn the ignition to LOCK/OFF in each shift lever position. - The ignition should turn to LOCK/OFF only when the shift lever is in P (Pa ...

OnStar®
If equipped, this vehicle has a comprehensive, in-vehicle system that can connect to a live Advisor for Emergency, Security, Navigation, Connection, and Diagnostic Services. See OnStar Overview. ...

Tachometer
The tachometer displays the engine speed in revolutions per minute (rpm). ...