Vehicle and Power Issues
OnStar services require a vehicle electrical system, wireless service, and GPS satellite technologies to be available and operating for features to function properly. These systems may not operate if the battery is discharged or disconnected.
See also:
How to Inspect the Engine Air Cleaner/Filter
To inspect the air cleaner/filter, remove the filter from the vehicle and lightly
shake the filter to release loose dust and dirt. If the filter remains covered with
dirt, a new filter is required ...
Electronic Transfer Case
The transfer case knob is located next to the steering column.
Use the dial to shift into and out of four-wheel drive. ...
Manual Operation of Power Liftgate
To change the liftgate to manual operation, turn the mode switch to the OFF position.
With the power liftgate disabled and all of the doors unlocked, the liftgate
can be manually opened and closed. ...