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. If the system is working normally, the indicator light then turns off. The tract ...

    Engine Power Messages
    ENGINE POWER IS REDUCED This message displays when the vehicle's engine power is reduced. Reduced engine power can affect the vehicle's ability to accelerate. If this message is on, but there i ...

    Belts
    • Belts may need replacing if they squeak or show signs of cracking or splitting. • Trained dealer technicians can inspect the belts and recommend replacement when necessary. ...