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:

    Crew Cab
    A. Open or Close B. Vent On vehicles with a sunroof, the sunroof only operates when the ignition is in the ACC/ACCESSORY or ON/RUN or the Retained Accessory Power (RAP) is active. See Retained Ac ...

    Fuel Economy Light
    For vehicles with the fuel economy mode light, it comes on when the eco (economy) switch, located on the center console near the shifter, is pressed. For vehicles with a Driver Information Cente ...

    Adding and Removing Categories
    Categories cannot be added or removed while the vehicle is moving faster than 8 km/h (5 mph). To add or remove a category: 1. Press the MENU button. 2. Press the softkey located below the XM CAT ta ...