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:

    Brake System Messages
    SERVICE BRAKE SYSTEM This message displays along with the brake system warning light if there is a problem with the brake system. See Brake System Warning Light on page 5‑21. If this message ap ...

    Chemical Paint Spotting
    Airborne pollutants can fall upon and attack painted vehicle surfaces causing blotchy, ring-shaped discolorations, and small, irregular dark spots etched into the paint surface. ...

    Increasing Speed While Using Cruise Control
    If the cruise control system is already activated: • Press and hold the +RES button on the steering wheel until the desired speed is reached, then release it. • To increase vehicle speed in smal ...