See also:

Automatic Dimming Rearview Mirror with OnStar® and Compass
Your vehicle may have an automatic-dimming rearview mirror with a compass and the OnStar® system. There are three additional buttons for the OnStar® system. See your dealer for more informatio ...

Automatic Operation
The system automatically controls the fan speed, air delivery, air conditioning, and recirculation in order to heat or cool the vehicle to the desired temperature. When the AUTO indicator lig ...

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 v ...