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:

    Exterior
    GM says the Yukon Hybrid's exterior changes are intended to make the SUV more aerodynamic compared with the gas-powered Yukon. A modified bumper drops the regular Yukon's fog lights for some chunk ...

    Brakes
    This vehicle has front disc brakes and could have rear drum brakes or rear disc brakes. Disc brake pads have built-in wear indicators that make a high-pitched warning sound when the brake pads are wo ...

    Cold Check Procedure
    Use this procedure only as a reference to determine if the transmission has enough fluid to be operated safely until a hot check procedure can be made. The hot check procedure is the most accurate met ...