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:

    Uniform Tire Quality Grading
    Quality grades can be found where applicable on the tire sidewall between tread shoulder and maximum section width. For example: ...

    Manual Operation of Power Liftgate
    To change the liftgate to manual operation, press OFF on the power liftgate switch. A message displays on the DIC indicating manual operation mode. See Driver Information Center (DIC) (Without DIC B ...

    If No Steam is Coming from the Engine Compartment
    The ENGINE OVERHEATED STOP ENGINE or the ENGINE OVERHEATED IDLE ENGINE message, along with a low coolant condition, can indicate a serious problem. If there is an engine overheat warning, but no stea ...