Pontiac 2005 G6 Owner's Manual page 130

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(Outside Air): Press the right side of this button to
turn the outside air mode on. When this mode is selected,
air from outside the vehicle will circulate throughout your
vehicle. When the button is pressed, an indicator light will
come on to let you know that it is activated. The outside
air mode can be used with all modes, but it cannot be
used with the recirculation mode. Pressing this button will
cancel the recirculation mode.
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(Recirculation): Press the left side of the button to
turn the recirculation mode on. When recirculation mode
is selected, the air inside the vehicle will be recirculated
through the climate control system and the vehicle, not
from outside your vehicle. This mode is helpful when you
are trying to limit odors from entering your vehicle and for
maximum air conditioning performance in hot weather.
When the button is pressed, an indicator light above the
button will come on to let you know that it is activated.
The recirculation indicator light will blink three times if you
try to use recirculation in a mode that it can not be used
in. Only use this mode when it is needed for comfort,
since window fogging will rapidly occur if the air
conditioning compressor is not engaged.
3-20
Pressing this button will cancel the outside air mode.
When you switch to the defog or defrost modes the
system will automatically move from recirculation to
outside air. When you move the mode knob back to
another air delivery mode, the system will move back into
recirculation. When the vehicle or fan is turned off and
back on, the system will default to outside air
automatically. Only use recirculation mode when it is
needed for comfort, since window fogging may occur.
Temperature Control: Turn the center knob clockwise
or counterclockwise to increase or decrease the
temperature inside your vehicle.
When it's cold outside 0°F ( 18°C) or lower, use the
engine coolant heater, if equipped, to provide warmer air
faster to your vehicle. An engine coolant heater warms
the coolant that the engine uses to provide heat to
warm the inside of your vehicle. For more information,
see Engine Coolant Heater on page 2-23.