See also:

Theft-Deterrent Feature
TheftLock® is designed to discourage theft of the vehicle's radio by learning a portion of the Vehicle Identification Number (VIN). The radio does not operate if it is stolen or moved to a different ...

Audio System
When using the Bluetooth system, sound comes through the vehicle's front audio system speakers and overrides the audio system. Use the VOL/ knob during a call to change the volume level. The a ...

New for 2011
The Sierra Hybrid gets GM's OnStar 9.0 telematics system that GM says provides better voice recognition. GM also said they have worked to cut down on the amount of wind noise occupants hear. ...