GMC 2003 Envoy - Manual (Page 147)

Rear Window Defogger
The I'rnes ytju sag on (he rear wlodtiw warm Ihg gia&s.
Press this butlon to torn the rear wpndow detoggar on or
off. An fndicator lighi in the button wiH come on to lei
you know that ihe rear window cielogger is aclive. The
rear window defogger will automatically turn off
approsimalely tan minutes aMef The button Is pressed^
If your vehicle is equipped with boated mirrors^ this
button will activate Iham.
Notice: Don't use anything sharp on the Inside o1
the rear window. If you do, you could cut or damage
the warming grid^ and the repairs wouldn't be
covered by your warranty. Do not attach a temporary
vehicle license, tape, a decal or anything similar
to the defogger grid.
Outlet Adjustment
Use the air gutlolg located in the cenler and on the side
of your instrumerit panel (o diragt the aidlow.
Ventilation System
For mifd outside temperatures when llttfa heating or
cooling is needed, use the vgni setting (o direct outside
air through your vehicle.
Vour vehicle's vanljlation system supplies outside air to
Ihc inside of your vehicle when it is moving. W№ the
side windows closed, air will flow into the front air inlet
grilles, through the vehicle and out tha air oxhausl
valves.
Outsido air Will also enter Ihe vehicta when the heater
or the air conditioning is running, unless you have
seJected recirculation mode.
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