GM Service Manual Online
For 1990-2009 cars only

Adjust all the mirrors so you can see clearly when you are sitting in a comfortable driving position.

To reduce glare from headlamps behind you, pull the lever at the bottom of the mirror toward you (to the night position). To return the mirror back to the day position, push the lever away from you.

There are two lamps located on the bottom of the mirror. Press the button next to each lamp to turn it on and off.