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:

    Engine Fan Noise
    Your vehicle has a clutched engine cooling fan. When the clutch is engaged, the fan spins faster to provide more air to cool the engine. In most everyday driving conditions the clutch is not eng ...

    LOW BATTERY
    This message is displayed when the battery voltage is low. See Battery for more information. ...

    Rainsense™ II Wipers
    If the vehicle has this feature, the moisture sensor is mounted on the interior of the windshield beside the rearview mirror and is used to automatically operate the wipers. This system operates ...