Diagnostics

OnStar Vehicle Diagnostics will perform a vehicle check every month. It will check the engine, transmission, antilock brakes, and major vehicle systems. It also checks the tire pressures, if the vehicle is equipped with the Tire Pressure Monitoring System. If a diagnostics check is needed between e-mails, push OnStar Additional Information, and an Advisor can run a check.

    See also:

    Compass Messages
    CAL This message is displayed when the compass needs to be calibrated. See Compass on page 5‑5. – – – Three dashes will be displayed if the compass needs service. See your dealer fo ...

    Driving on Grades
    Reduce speed and shift to a lower gear before starting down a long or steep downgrade. If the transmission is not shifted down, the brakes might have to be used so much that they would get hot and ...

    Shifting Out of Neutral
    To shift out of N (Neutral) do the following: 1. Set the parking brake and apply the regular brake pedal. 2. Turn the ignition to ON/RUN with the engine off, and shift the transmission to N (Neutral ...