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:

    Auxiliary Battery
    The auxiliary battery provision can be used to supply electrical power to additional equipment that may be added, such as a slide-in camper. If the vehicle has this provision, this relay will be loca ...

    Reporting Safety Defects to General Motors
    In addition to notifying NHTSA (or Transport Canada) in a situation like this, please notify General Motors. Call 1-800-GMC-8782 (1-800-462-8782), or write: GMC Customer Assistance Center P.O. Box ...

    Ride Control System Messages
    SERVICE STABILITRAK This message displays if there is a problem with the StabiliTrak® system. If this message appears, try to reset the system. Stop; turn off the engine for at least 15 seconds; th ...