1996 GMC Yukon Owner's Manual - Page 141

Rear Window Defogger (Option) If you see lines running across the rear window. you have the rear window defogger. The lines warm the glass. Do not attach a temporary vehicle license, tape or decals across the defogger grid on the rear window. I NOTICE: Don't use a razor blade something else sharp or on the inside of'the rear window. you do, you If could cut or damage the warming grid, and the repairs wouldn'tbe covered by your warranty. To turn on the rear window defogger, press this button next to the fan control knob. The rear window defogger will only work if the ignition switch is turned to RUN. For best results, first clear the window of as much snow or ice as possible. Audio Systems Your DelcoB audio system has been designed to operate easily and give years of listening pleasure. You will get the most en-joymentout of it if you acquaint yourself with it first. Find out what your Delco system can do and how to operate all its controls, to be sure you're getting the most out of the advanced engineering that went into it. The defogger will shut itself off after several minutes. If you need additional warming time, press the button again. You can turn the defomer off at any time by pressing the button. 3-9