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 to Add Engine Oil
    If the oil is below the cross-hatched area at the tip of the dipstick, add 1 L (1 qt) of the recommended oil and then recheck the level. See “Selecting the Right Engine Oil” in this section for ...

    Scheduling Service Appointments (U.S. and Canada)
    When the vehicle requires warranty service, contact your dealer and request an appointment. By scheduling a service appointment and advising the service consultant of your transportation needs, your ...

    When It Is Time for New Tires
    Factors such as maintenance, temperatures, driving speeds, vehicle loading, and road conditions affect the wear rate of the tires. Treadwear indicators are one way to tell when it is time for new ...