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:

    When the Light Is On Steady
    This indicates that one or more of the tires are significantly underinflated. A Driver Information Center (DIC) tire pressure message may also display. See Vehicle Messages  for more informati ...

    Convex Mirrors
    WARNING! A convex mirror can make things, like other vehicles, look farther away than they really are. If you cut too sharply into the right lane, you could hit a vehicle on the right. Chec ...

    Horn
    Press on the steering wheel pad to sound the horn. ...