Defogging And Defrosting - GMC 2001 Sierra 1500 Pickup Owner's Manual

Heating
The heater works best if you keep your windows closed
while using it. On cold days, use the HEATER or
VENT/HEAT setting with the temperature knob in the
red area.
On cold days, approximately 32 _ F (
if your vehicle is equipped with an automatic transmission,
you may experience differences in how the transmission
shifts until the engine is warm. This feature automatically
reduces the time it takes for the engine to reach normal
operating temperature and shortens the time it takes the
heater to reach full output.
If you use the engine coolant heater before starting your
engine in cold weather, 20 _ F (
heating system will produce warmer air faster to heat the
passenger compartment.
The use of an engine coolant heater also reduces the
time it takes for the engine to reach normal operating
temperature. For more information, see "Engine Coolant
Heater" in the Index.
0 _ C) or lower,
-
8 _ C) or lower, the
-

Defogging and Defrosting

On cool, humid days, use DEFOG to keep the
windshield and side windows clear. Use DEFROST to
remove fog or ice from the windshield in extremely
humid or cold conditions. Use DEFROST with the
temperature knob toward the red area and the fan
control turned all the way to the right.
Rear Window Defogger (If Equipped)
If you see lines running across the rear window, you
have a rear window defogger. The lines warm the glass.
To turn on the rear window
defogger, press this button
next to the fan knob.
The rear window
defogger will only work
if the ignition is in RUN.
For best results, clear the
window of as much snow
or ice as possible.
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