2007 GMC YUKON XL air condition

Defogging and Defrosting
Fog on the inside of the windows is a result of
high humidity (moisture) condensing on the
cool window glass. This can be minimized if the
climate control system is used properly. There
are two modes to clear fog or frost from your
windshield. Turn the right knob clockwise to select
the defog or defrost mode.
-(Defog):The defog mode is used to clear
the windows of fog or moisture and warm
the passengers. This mode directs air to the
windshield, oor outlets, and side window vents.
When you select this mode, the system turns
off recirculation and runs the air conditioning
compressor unless the outside temperature is
close to freezing. The recirculation mode cannot
be selected while in the defog mode. Do not drive
the vehicle until all the windows are clear.
0(Defrost):The defrost mode is used to
remove fog or frost from the windshield more
quickly. This mode directs a portion of the air to
the windshield and side window vents and some to
the oor vents. In this mode, the system will
automatically force outside air into your vehicle.
The recirculation mode cannot be selected while in
the defrost mode. The air conditioning compressor
will run automatically in this setting, unless the
outside temperature is close to freezing.
Do not drive the vehicle until all the windows
are clear.
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Automatic Operation
AUTO (Automatic):When automatic operation
is active the system will control the inside
temperature, the air delivery, and the fan speed.
Use the steps below to place the entire system in
automatic mode:
1. Press the AUTO button.
When AUTO is selected, the display will
change to show the current temperature(s)
and AUTO will be lit on the display. The current
delivery mode and fan speed will also be
displayed for approximately 5 seconds.
When AUTO is selected, the air conditioning
operation and air inlet will be automatically
controlled. The air conditioning compressor will
run when the outside temperature is over
about 40°F (4°C). The air inlet will normally be
set to outside air. If it’s hot outside, the air
inlet may automatically switch to recirculate
inside air to help quickly cool down your
vehicle. The light on the button will illuminate
in recirculation.2. Set the driver’s and passenger’s temperature.
To nd your comfort setting, start with a
74°F (23°C) temperature setting and allow
about 20 minutes for the system to regulate.
Use the driver’s or passenger’s temperature
buttons to adjust the temperature setting as
necessary. If you choose the temperature
setting of 60°F (15°C), the system will remain at
the maximum cooling setting. If you choose the
temperature setting of 90°F (32°C), the system
will remain at the maximum heat setting.
Choosing either maximum setting will not cause
the vehicle to heat or cool any faster.
Be careful not to cover the sensor located on the
top of the instrument panel near the windshield.
This sensor regulates air temperature based
on sun load and also turns on your headlamps.
To avoid blowing cold air in cold weather, the
system will delay turning on the fan until warm air
is available. The length of delay depends on
the engine coolant temperature. Pressing the fan
switch will override this delay and change the
fan to a selected speed.
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O(On/Off):Press this button to turn off the
climate control system. Outside air will still enter
the vehicle, and will be directed to the oor.
This direction can be changed by pressing the
mode button. Recirculation can be selected once
you have selected vent or bi-level mode. The
temperature can also be adjusted using either
temperature button. If you adjust the air delivery
mode or temperature settings with the system
off, the display will illuminate briey to show you
the settings and then return off. Press the
on/off button or the up down arrows on the fan
switch, the defrost button, AUTO button, or the air
conditioning button to turn the system on when
it is off.
Manual Operation
You may manually adjust the air delivery mode or
fan speed.
y9 z(Fan):The buttons with the fan symbols
allow you to manually adjust the fan speed.
Press the up arrow to increase fan speed and the
down arrow to decrease fan speed.Pressing one of these buttons when the system is
off will turn the system on. Pressing one of
these buttons when in automatic control will place
the fan under manual control. The fan setting
will remain displayed and the AUTO light will turn
off. The air delivery mode will remain under
automatic control.
yNz(Mode):Press the mode up and down
buttons to manually change the direction of
the airow in your vehicle. Repeatedly press the
button until the desired mode appears on the
display. Pressing one of these buttons when the
system is off will change air delivery mode without
turning the system on. Pressing one of these
buttons when in automatic control will place the
mode under manual control.
The air delivery mode setting will be displayed and
the AUTO light will turn off. The fan will remain
under automatic control.
H(Vent):This setting will deliver air to the
instrument panel outlets.
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)(Bi-Level):This mode directs half of the air
to the instrument panel outlets and to the oor
outlets. The ow can be divided between vent and
oor outlets depending upon where the knob is
placed between the settings. A little air is directed
towards the windshield and side window outlets.
Cooler air is directed to the upper outlets and
warmer air to the oor outlets.
6(Floor):This mode directs most of the air to
the oor outlets, with some of the air directed
to the windshield, side window outlets, and
second row oor outlets. In this mode, the system
will automatically select outside air.
-(Defog):See “Defogging and Defrosting” later
in this section.
@(Recirculation):Press this button to turn
the recirculation mode on. When the button
is pressed, an indicator light will come on.
This mode keeps outside air from entering the
vehicle. It can be used to reduce outside air and
prevent odors from entering your vehicle.
Recirculation may also help cool the air inside
your vehicle more quickly once the temperature
inside the vehicle is less than the outside
temperature.
The recirculation mode cannot be used with oor,
defrost, or defogging modes. If you try to select
recirculation in one of those modes, the indicator
will ash three times and turn off. The air
conditioning compressor will also come on when
this mode is activated. While in recirculation mode
the windows may fog when the weather is cold
and damp. To clear the fog, select either the defog
or defrost mode and increase the fan speed.
Recirculation mode can be turned off by pressing
the button again, or turning off the engine.
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Air Conditioning
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(Air Conditioning):Press this button to turn
the air conditioning (A/C) compressor on and
off. When air conditioning is selected, an indicator
light will come on to let you know that the air
conditioning has been activated.
Pressing this button when the outside temperature
is too cool for air conditioning will make the air
conditioning indicator ash three times and
then turn off to let you know the air conditioning
mode is not available. If the air conditioning
is on and the outside temperature drops below a
temperature which is too cool for air conditioning
to be effective, the air conditioning light will turn off
to let you know the air conditioning mode has
been canceled.
On hot days, open the windows long enough to let
hot inside air escape. This helps to reduce the
time it takes for your vehicle to cool down. It also
helps the system to operate more efficiently.
The air conditioning system removes moisture from
the air, so you may sometimes notice a small
amount of water dripping underneath your vehicle
while idling or after turning off the engine. This
is normal.
Defogging and Defrosting
Fog on the inside of the windows is a result of
high humidity (moisture) condensing on the
cool window glass. This can be minimized if the
climate control system is used properly. There are
two modes to clear fog or frost from your
windshield.
Use the mode up and down arrows to select the
defog or defrost modes.
-(Defog):The defog mode is used to clear the
windows of fog or moisture and warm the
passengers. This mode directs air to the
windshield, oor outlets, and side window vents.
When you select this mode, the system turns
off recirculation and runs the air conditioning
compressor unless the outside temperature is
close to freezing. The recirculation mode cannot
be selected while in the defog mode. Do not drive
the vehicle until all the windows are clear.
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0(Defrost):Press this button to remove fog or
frost from the windshield more quickly. This
mode directs a portion of the air to the windshield
and side window vents and some to the
oor vents. In this mode, the system will
automatically force outside air into your vehicle.
The recirculation mode cannot be selected while in
the defrost mode. The air conditioning compressor
will run automatically in this setting, unless the
outside temperature is close to freezing. Do
not drive the vehicle until all the windows are clear.Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog from the rear window.
<(Rear Window Defogger):Press this button
to turn on the rear window defogger. It will
automatically turn off several minutes after it has
been activated. The defogger can also be
turned off by pressing the button again or by
turning off the engine. Do not drive the vehicle until
all the windows are clear.
If your vehicle has heated outside rearview
mirrors, the mirrors will heat to help clear fog or
frost from the surface of the mirror when the
rear window defog button is pressed.
Notice:Do not use a razor blade or sharp
object to clear the inside rear window. Do not
adhere anything to the defogger grid lines
in the rear glass. These actions may damage
the rear defogger. Repairs would not be
covered by your warranty.
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Outlet Adjustment
Use the air outlets located in the center and on
the side of your instrument panel to direct
the airow.
Operation Tips

Keep the hood and front air inlets free of ice,
snow, or any other obstruction (such as
leaves). The heater and defroster will work far
better, reducing the chance of fogging the
inside of your windows.
When you enter a vehicle in cold weather,
press the fan up button to the maximum
fan level before driving. This helps clear the
intake ducts of snow and moisture, and
reduces the chance of fogging the inside of
your window.
Keep the air path under the front seats clear
of objects. This helps air to circulate
throughout your vehicle.
Adding outside equipment to the front of your
vehicle, such as hood-air deectors, may affect
the performance of the heating and air
conditioning system. Check with your dealer
before adding equipment to the outside of your
vehicle.
Rear Air Conditioning and Heating
System
If your vehicle has this system, the rear controls
are three knobs located in the headliner.
The system can be controlled from the front
controls as well as the rear controls.
To turn the system on, press the AUX button on
the front climate control system, an indicator will be
lit. Pressing the AUX button the rst time will
turn the rear system on in a mimic mode. In this
mode, the airow in the rear will be approximately
the same direction, temperature, and fan speed
as the front. Pressing the AUX button again
will turn the rear system and the indicator off.
If the rear controls are adjusted, the system will
enter a rear independent mode. Airow in the rear
will then be directed according to the settings of
rear controls. The rear system can be turned off by
pressing the AUX button on the front climate
control system and the indicator will turn off.
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Rear Air Conditioning and Heating
System and Electronic Climate
Controls
If your vehicle has this system, the rear heat and
air conditioning controls are integrated with the
rear seat audio controls located in the center
console. The system can be controlled from the
front controls as well as the rear controls.
To turn the system on, press the AUX button on
the front climate control system, an indicator will be
lit. Pressing the AUX button the rst time will
turn the rear system on in a mimic mode. In this
mode, the airow in the rear will be approximately
the same direction, temperature, and fan speed
as the front. Pressing the AUX button again
will turn the rear system and the indicator off.If the rear controls are adjusted, the system will
enter a rear independent mode. Airow in the rear
will then be directed according to the settings of
rear controls. The rear system can be turned off by
pressing the AUX button on the front climate
control system and the indicator will turn off.
If the indicator in the front AUX button is off, the
rear system is off.
Rear Control Integrated with Rear Seat Audio
Controls
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