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:

    Fuel E85 (85% Ethanol)
    Vehicles that have a FlexFuel badge and a yellow fuel cap can use either unleaded gasoline or ethanol fuel containing up to 85% ethanol (E85). See Fuel E85 (85% Ethanol) on page 9‑76. For all o ...

    Canceling a Remote Start
    To cancel a remote start: • Aim the RKE transmitter at the vehicle and press and hold until the parking lamps turn off. • Turn on the hazard warning flashers. • Turn the ignition on and t ...

    Vehicle Storage
    Tires age when stored normally mounted on a parked vehicle. Park a vehicle that will be stored for at least a month in a cool, dry, clean area away from direct sunlight to slow aging. This area sh ...