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:

    Speedometer
    The speedometer shows how fast the vehicle is moving in either kilometers per hour (km/h) or miles per hour (mph). The speedometer cannot be reset. ...

    Engine Coolant Temperature Gauge
    Metric English This gauge measures the temperature of the vehicle's engine. If the indicator needle moves to the hot side of the gauge toward the colored line, the engine is too hot. If ...

    Service Vehicle Messages
    SERVICE A/C (Air Conditioning) SYSTEM This message displays when the electronic sensors that control the air conditioning and heating systems are no longer working. Have the climate control system s ...