GMC Yukon Denali 2003 Owner's Manual page 169

Driver Overhead Control
Front Controls
To control the rear climate control from the front seat
position, use the driver overhead control. The rear
console control must be on.
AUX: Turn the knob, located on the left side of the
control panel, to this position to allow the rear seat
passengers to have control over the rear climate control
system. See "Rear Passenger Console Control" later
for more information.
9
(Off): Turn the knob, located on the left side of the
control panel, to this position to turn the rear climate
control system off.
9
(Fan): To adjust the airflow speed, turn the fan
knob located on the left side of the control panel to the
desired setting. Choose AUTO if you want the system
to automatically choose the fan speed to maintain
a selected temperature. See "Auto Mode" later in this
section for more information on using this feature.
°F (°C): To adjust the air temperature, turn the
temperature knob on the center of the control panel. For
cooler or warmer air turn the knob counterclockwise
toward 66°F (19°C) or clockwise toward 82°F (27°C).
To regulate the airflow direction, adjust the right knob on
the control panel. Turn the knob clockwise for floor
vent airflow or counterclockwise for headliner vent
airflow. Generally, the upper vents are used for air
conditioning and the floor vents for heating. The knob
can be set to any blend setting. Choose AUTO if
you want the system to automatically regulate the
airflow. See "Auto Mode" later in this section for more
information on using this feature.
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