Ventilation System - Chevrolet 2002 Silverado 1500 Pickup Owner's Manual

The defogger will shut itself off after several minutes.
If you need additional warming time, press the button
again. You can turn the defogger off at any time by
pressing the button.
If your vehicle is equipped with heated outside mirrors,
the rear window defogger button will also activate the
heated outside mirrors.
Do not attach a temporary vehicle license, tape or decals
across the defogger grid on the rear window.
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.

Ventilation System

For mild outside temperatures when little heating or
cooling is needed, use vent to direct outside air through
your vehicle.
Your vehicle's ventilation system supplies outside air to
the inside of your vehicle when it is moving. With the
side windows closed, air will flow into the front air
inlet grilles, through the vehicle, and out the air
exhaust valves.
Outside air will also enter the vehicle when the floor or
the air conditioning fan is running, unless you have the
recirculation button pushed in. For more information on
the recirculation mode, see "Air Conditioning" earlier in
this section.
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