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:

    Windshield Washer
    WARNING In freezing weather, do not use the washer until the windshield is warmed. Otherwise the washer fluid can form ice on the windshield, blocking your vision. (Washer Fluid): Push the paddle ...

    Gasoline Specifications (U.S. and Canada Only)
    At a minimum, gasoline should meet ASTM specification D 4814 in the United States or CAN/CGSB&-3.5 or 3.511 in Canada. Some gasolines contain an octane-enhancing additive called methylcyclopen ...

    Hydroplaning
    Hydroplaning is dangerous. Water can build up under the vehicle's tires so they actually ride on the water. This can happen if the road is wet enough and you are going fast enough. When the vehicle i ...