2006 GMC Envoy Owner's Manual - Page 166

Defogging and Defrosting Fog on the inside of windows is a result of high humidity (moisture) condensing on the cool window glass. This can be minimized if the climate control system is used properly. There are two modes to choose from to clear fog or frost from your windshield. Use the defog mode to clear the windows of fog or moisture and warm the passengers. Use the defrost mode to remove fog or frost from the windshield more quickly. Turn the right knob clockwise or counterclockwise to select one of the following modes: Rear Window Defogger The lines you see on the rear window warm the glass. < (Rear): Press this button to turn the rear window defogger on or off. An indicator light in the button will come on to let you know that the rear window defogger is active. The rear window defogger will automatically turn off approximately ten minutes after the button is pressed. If your vehicle is equipped with heated mirrors, this button will activate them. Notice: Do not use anything sharp on the inside of the rear window. If you do, you could cut or damage the warming grid, and the repairs would not be covered by your warranty. Do not attach a temporary vehicle license, tape, a decal or anything similar to the defogger grid. - (Defog): This mode directs the air to the floor outlets, windshield and side window outlets. The recirculation button cannot be selected while in defog mode. 1 (Defrost): This mode directs most of the air to the windshield and the side window outlets, with only a little air directed to the floor outlets. The air conditioning compressor may run to dehumidify the air to prevent window fogging. The recirculation button cannot be selected while in defrost mode. Do not drive the vehicle until all the windows are clear. 3-22