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:

    Filling the Tank
    If the vehicle has a diesel engine, see the Duramax diesel supplement for more information. WARNING Fuel vapor burns violently and a fuel fire can cause bad injuries. To help avoid injuries to you ...

    When Should an Airbag Inflate?
    Frontal airbags are designed to inflate in moderate to severe frontal or near frontal crashes to help reduce the potential for severe injuries, mainly to the driver's or front outboard passenger's hea ...

    When the Light Flashes First and Then Is On Steady
    If the light flashes for about a minute and then stays on, there may be a problem with the TPMS. If the problem is not corrected, the light will come on at every ignition cycle. See Tire Pressure Mon ...