GMC 2007 Yukon XL Owner's Manual page 221

Fan Knob
Turn the left knob clockwise or counterclockwise
to increase or decrease the fan speed. Turn
the knob all the way counterclockwise to turn the
rear system off.
Temperature Knob
The middle knob on the control panel lets you
select the temperature of the air flowing into the
passenger area. Turn the knob clockwise
toward the red area for warmer air. Turn the knob
counterclockwise toward the blue area for
cooler air.
Mode Knob
The right knob on the control panel allows you to
choose the direction of air delivery.
H
(Vent): This setting directs the air through the
headliner outlets.
)
(Bi-Level): Air is delivered through the floor
outlets as well as the headliner outlets. The rear
system floor outlets are located directly behind the
second row seats. The flow can be divided between
vent and floor outlets depending upon where the
knob is placed between the settings.
6
(Floor): This setting directs most of the air
through the floor outlets. The rear system floor
outlets are located directly behind the
second row seats.
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