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:

    General Information
    This maintenance section applies to vehicles with a gasoline engine. For diesel engine vehicles, see the maintenance schedule section in the Duramax Diesel Supplement. Your vehicle is an important in ...

    Leaving the Vehicle With the Engine Running
    WARNING It can be dangerous to leave the vehicle with the engine running. The vehicle could move suddenly if the shift lever is not fully in P (Park) with the parking brake firmly set. And, if yo ...

    Driving with a Trailer
    WARNING When towing a trailer, exhaust gases may collect at the rear of the vehicle and enter if the liftgate, trunk/hatch, or rear-most window is open. Engine exhaust contains Carbon Monoxide (CO) ...