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:

    Windows
    WARNING Leaving children, helpless adults, or pets in a vehicle with the windows closed is dangerous. They can be overcome by the extreme heat and suffer permanent injuries or even death from hea ...

    If the Vehicle Is Stuck
    Slowly and cautiously spin the wheels to free the vehicle when stuck in sand, mud, ice, or snow. If the vehicle has a traction system, it can often help to free a stuck vehicle. Refer to the vehicle' ...

    Checking Coolant
    The coolant surge tank is located in the engine compartment on the passenger side of the vehicle. See Engine Compartment Overview on page 10‑6 for more information on location. The vehicle must ...