1997 Chevrolet Blazer Owner's Manual - Page 144

Defogging and Defrosting On cool, humid days. use BLEND to keep the windshield and side windows clear. Use DEFROST to remove fog or ice from the windshield quickly in extreme humid or cold conditions. Turn the temperature knob clockwise and move the fan control toward HI. window of as much snow or ice as possible before using the rear window defogger. To turn on the rear window defogger. find the switch marked REAR DEFOG on your instrument panel below the headlamp switch. Press ON until the light in the switch comes on,then release it. it will only work if the ignition switch is turned to RUN. The rear window defogger will stay on for five to seven minutes, then turn off. If you need additional warming time, turn it on again. You can turn the defogger off at any time by pressing OFF. Rear Window Defogger (Option) Do not attach a temporary vehicle license. tape or decals across the defogger grid on the rear window. 1 NOTICE: Don't use a razor blade or something else sharp on the inside of the rear window. If you do, you could cut or damage the warming grid, and the repairs wouldn't be covered by your warranty. I f your vehicle has this option, the rear window will have lines that warm the glass. For best results. clear the 3-5