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:

    Traction Off Light
    This light comes on briefly while starting the engine. If it does not, have the vehicle serviced by your dealer. This light comes on when the Traction Control System (TCS) has been turned ...

    Maintenance When Trailer Towing
    Your vehicle will need service more often when you’re pulling a trailer. See the Maintenance Schedule for more on this. Things that are especially important in trailer operation are automatic tr ...

    Filling a Portable Fuel Container
    WARNING Never fill a portable fuel container while it is in the vehicle. Static electricity discharge from the container can ignite the fuel vapor. You can be badly burned and the vehicle damaged ...