Chevrolet 2001 Monte Carlo Owner's Manual page 179

Rear Window Defogger
When turned on, the rear window defogger uses a
warming grid to remove fog from the rear window. If
your vehicle has the heated outside rearview mirrors, they
will heat to clear the mirror surface before driving. The
rear window defogger and the mirrors will automatically
turn off after about 15 minutes. If you turn them on
again, the defogger and the mirrors will only stay on
for about seven and one half minutes before turning
off again. You can also turn them off by turning the
ignition off or by pressing the button again.
Press the button marked
REAR to turn the defogger
on. An indicator on the
button will light.
Do not attach anything like a temporary vehicle license
or decal across the defogger grid.
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.
Don't put decals there because you might have
to scrape them off.
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