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:

    Full-Size Spare Tire
    Your vehicle, when new, had a fully-inflated spare tire. A spare tire may lose air over time, so check its inflation pressure regularly. See Tire Pressure on page 10‑62 and Vehicle Load Limits o ...

    Pulling a Trailer
    Here are some important points: ○ There are many laws, including speed limit restrictions that apply to trailering. Check for legal requirements with state or provincial police. ○ Do n ...

    How to Reset the Engine Oil Life System
    Reset the system whenever the engine oil is changed so that the system can calculate the next engine oil change. To reset the system: 1. Turn the ignition to ON/RUN, with the engine off. 2. Press ...