TTY Users

OnStar has the ability to communicate to the deaf, hard-of-hearing, or speech-impaired customers while in the vehicle. The available dealer-installed TTY system can provide in-vehicle access to all of the OnStar services, except Virtual Advisor and OnStar Turn-by-Turn Navigation.

    See also:

    Ignition Positions
    The ignition switch has four different positions. In order to shift out of P (Park), the ignition must be in ON/RUN or ACC/ACCESSORY and the brake pedal must be applied. Notice: Using a tool to fo ...

    Cooling System
    If the vehicle has the Duramax® Diesel engine, see the Duramax® Diesel Supplement for more information. The cooling system allows the engine to maintain the correct working temperature. 5.3 L En ...

    Radio Messages
    Calibration Error: The audio system has been calibrated for the vehicle from the factory. If Calibration Error displays, it means that the radio has not been configured properly for the vehicle and i ...