See also:

Your Responsibility
Increase the volume of the radio if the OnStar Advisor cannot be heard. If the light next to the OnStar buttons is red, the system may not be functioning properly. Push and request a vehicle diagnos ...

When the Light Is On Steady
This indicates that one or more of the tires are significantly underinflated. A Driver Information Center (DIC) tire pressure message may also display. See Vehicle Messages for more informati ...

Engine Heater
The engine coolant heater, if available, can help in cold weather conditions at or below −18°C (0°F) for easier starting and better fuel economy during engine warm-up. Plug in the coolant hea ...