See also:

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 vehic ...

Shifting Into Four-Wheel Drive High or AUTO (Automatic Four-Wheel Drive)
Turn the knob to the Four-Wheel Drive High or AUTO position. This can be done at any speed, except when shifting from Four-Wheel Drive Low. The indicator light will flash while shifting. It will remai ...

Crew Cab
A. Open or Close B. Vent On vehicles with a sunroof, the sunroof only operates when the ignition is in the ACC/ACCESSORY or ON/RUN or the Retained Accessory Power (RAP) is active. See Retained Ac ...