Vehicle and Power Issues

OnStar services require a vehicle electrical system, wireless service, and GPS satellite technologies to be available and operating for features to function properly. These systems may not operate if the battery is discharged or disconnected.

    See also:

    Tow/Haul Mode
    4-Speed Automatic Transmission 6-Speed Automatic Transmission Vehicles with an automatic transmission have a Tow/Haul Mode. The Tow/Haul Mode adjusts the transmission shift pattern to reduce shi ...

    TTY Users
    OnStar has the ability to communicate to the deaf, hard&-ofhearing, or speech&-impaired customers while in the vehicle. The available dealer&-installed TTY system can provide in-vehicl ...

    Parking Brake
    To set the parking brake, hold the regular brake pedal down, then push the parking brake pedal down. If the ignition is on, the brake system warning light will come on. See Brake System Warning Li ...