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:

    Before Driving Off-Road
    • Have all necessary maintenance and service work completed. • Fuel the vehicle, fill fluid levels, and check inflation pressure in all tires, including the spare, if equipped. • Read all the ...

    Engine Oil Messages
    CHANGE ENGINE OIL SOON This message displays when the engine oil needs to be changed. When you change the engine oil, be sure to reset the CHANGE ENGINE OIL SOON message. See Engine Oil Life System ...

    Starting the Engine
    Move the shift lever to P (Park) or N (Neutral). The engine will not start in any other position. To restart the vehicle when it is already moving, use N (Neutral) only. Notice: Do not try to shi ...