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:

    Automatic Operation
    AUTO (Automatic): The system automatically controls the inside temperature, the air delivery, and the fan speed. To use automatic mode: 1. Press the AUTO button. When AUTO is selected, the current ...

    If No Steam is Coming from the Engine Compartment
    If an engine overheat warning is displayed but no steam can be seen or heard, the problem may not be too serious. Sometimes the engine can get a little too hot when the vehicle: ○ Climbs a ...

    Reducing Speed While Using Cruise Control
    If the cruise control system is already activated: • Press and hold the SET– button on the steering wheel until the lower speed desired is reached, then release it. • To slow down in small amo ...