2005 GMC YUKON ac system

Driver’s Side Temperature Knob
The driver’s side knob is used to adjust the temperature
of the air coming through the system on the driver’s
side. The temperature can be adjusted even if the
system is turned off. This is possible since outside air
will always ow through the system as the vehicle
is moving forward unless it is set to recirculation mode.
See “Recirculation” later in this section.
Turn the knob counterclockwise or clockwise to lower or
increase the cabin temperature. The display will show
the temperature setting decreasing or increasing and an
arrow pointing to the driver will be displayed under
and to the left of the temperature setting.
Passenger’s Side Temperature Knob
The passenger’s side knob can be used to change the
temperature of the air coming through the system
on the passenger’s side of the vehicle. The temperature
can be adjusted even if the system is turned off. This
is possible since outside air will always ow through the
system as the vehicle is moving forward unless it is
set to recirculation mode. See “Recirculation” later in
this section.
Turn the knob counterclockwise or clockwise to lower
or increase the temperature inside the vehicle. The
display will show the temperature setting decreasing or
increasing and an arrow pointing to the passenger
will be displayed under and to the right of the
temperature setting.The passenger’s temperature setting can be set to
match the driver’s temperature setting by pressing and
holding the AUTO button for four seconds. Both the
driver and passenger arrows will be displayed.
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 driver’s set temperature, delivery
mode and fan speed. Press the AUTO button again
within ve seconds to display the passenger’s set
temperature.
If the driver and passenger’s temperature settings
are not the same, the opposite side temperature
setting will be displayed for an additional ve
seconds. To make the passenger’s temperature the
same as the driver’s, press and hold the AUTO
button for about four seconds.
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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. Turn the driver’s or
passenger’s side temperature knob 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.
9(Off):Press this button to turn off the entire 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. The
temperature can also be adjusted using either
temperature knob. Press the up or down arrows on the
fan switch, the defrost button, the 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.
w9x(Fan):The switch with the fan symbol allows
you to manually adjust the fan speed. Press the up
arrow to increase fan speed and the down arrow
to decrease fan speed.
Pressing this button when the system is off will turn the
system on.
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C(Mode):Press this button to manually change the
direction of the airow in your vehicle; keep pressing the
button until the desired mode appears on the display.
If you press the mode button to select an air delivery
mode, the display will change to show you the selected
air mode delivery. The display will then show the
current status of the system. When the system is turned
off, the display will go blank after displaying the
current status of the system.
H(Panel):This setting will deliver air to the
instrument panel outlets.
)(Bi-Level):This setting will deliver warmer air to the
oor and cooler air to the instrument panel outlets.
6(Floor):This setting will deliver air to the oor
outlets.
-(Defog):See “Defogging and Defrosting” later in
this section.
@(Recirculation):Press this button to limit the
amount of outside air entering your vehicle. The light on
the recirculation button will glow. This is helpful when you
are trying to limit odors entering your vehicle and for
maximum air conditioning performance in hot weather.
Press this button again to allow outside air to enter the
vehicle. The light on the recirculation button will go off.Pressing this button also cancels the auto recirculation
feature. To resume the auto recirculation function, press
the AUTO button. Each time the vehicle is started, the
system will revert to the auto recirculation function.
If you select recirculation while in defrost, defog or oor,
the light in the button will ash and then go out to let you
know that this is not allowed. This is normal and helps to
prevent fogging.
When the weather is cool or damp, operating the system
in recirculation for extended periods of time may cause
fogging of the vehicle’s windows. To clear the fog, select
either defog or front defrost.
You may also notice that the A/C compressor will run
while in recirculation mode. This is normal and helps to
prevent fogging.
9(Off):Press this button to turn off the entire 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. The temperature can also
be adjusted using either temperature knob. Press the up
or down arrows on the fan switch, the defrost button, the
AUTO button, or the air conditioning button to turn the
system on when it is off.
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Display
If you press the MODE button to select an air delivery
mode, the display will change to show you the selected
air delivery mode. After 10 seconds, the display will
change to show the driver’s temperature setting and the
selected mode.
If you press the up or down arrows on the fan switch,
the display will change to show the selected fan speed.
After 10 seconds, the display will change to show the
driver temperature setting and the selected mode.
Whenever you press AUTO, the display will change to
show the following:
The current driver’s set temperature and an arrow
for ve seconds
The current passenger’s set temperature setting
and an arrow for ve seconds
The automatic air delivery mode and fan speed
If the driver’s and passenger’s temperature settings are
the same when AUTO is pressed, the temperature setting
and both arrows will be displayed for ve seconds along
with the automatic air delivery mode and fan speed. After
the ve second update, the display will change to show
the temperature setting, both arrows and AUTO.
Air Conditioning
#
(Air Conditioning):Press this button to turn the
air conditioning (A/C) compressor on and off. The
snowake symbol will appear on the display when the
A/C is on and will turn off when the air conditioning is off.
Pressing this button when the outside temperature is
too cool for air conditioning will make the snowake
symbol 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 snowake symbol will
turn off to let you know the air conditioning mode
has been canceled.
When air conditioning is selected or in AUTO mode,
the system will run the air conditioning automatically
to cool and dehumidify the air entering the vehicle.
If you select A/C off while in front defrost, defog
or recirculation, the A/C snowake symbol will turn off,
but the A/C compressor will still run to help prevent
fogging.
On hot days, open the windows long enough to let hot
inside air escape. This reduces the time it takes for
your vehicle to cool down. Then keep your windows
closed for the air conditioner to work its best.
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On cool, but sunny days while using manual operation
of the automatic system, use bi-level to deliver warm
air to the oor and cooler air to the instrument
panel outlets. To warm or cool the air delivered, turn the
temperature knob to the desired setting.
In AUTO mode the system will cool and dehumidify the
air inside the vehicle. Also while in AUTO mode, the
system will maximize its performance by using
recirculation as necessary.
Defogging and Defrosting
You can use either defog or front defrost to clear fog
or frost from your windshield. Use the defog mode
to clear the windows of fog or moisture. Use the front
defrost button to defrost the front windshield.
-(Defog):Use this setting to clear the windows of
fog or moisture. Press the mode button to select
this setting. This setting will deliver air to the oor
and windshield outlets.
0(Defrost):Press the defrost button to defrost the
windshield. The system will automatically control the fan
speed if you select defrost from AUTO mode. If the
outside temperature is 40°F (4°C) or warmer, your air
conditioning compressor will automatically run to
help dehumidify the air and dry the windshield.
Rear Window Defogger
Your vehicle has this feature. The lines you see
on the rear window warm the glass. The rear window
defogger uses a warming grid to remove fog from
the rear window.
<(Rear):Press this button to turn the rear window
defogger on or off. An indicator light in the button
will come on to let you know that the rear window
defogger is activated.
The rear window defogger will turn off about 10 minutes
after the button is pressed. If you need additional
warming time, press the button again.
Your vehicle is equipped with heated mirrors. This
button will activate them.
Notice:Using a razor blade or sharp object to
clear the inside rear window may damage the rear
window defogger. Repairs would not be covered
by your warranty. Do not clear the inside of the rear
window with sharp objects.
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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, turn the
fan knob all the way to the right for a few moments
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 System
If your vehicle has the optional rear air conditioner, it
has two rear air conditioning fan speed selectors.
One fan speed selector is located in the overhead
console and the other is located in the headliner above
the second row seats.
To increase and decrease the ow of cooled air to the
rear vents, turn the knob to the fan speed you want.
The knob has three speed positions. To increase
the ow of cooled air, turn the knob clockwise. To
decrease the ow of cooled air, turn it counterclockwise.
To turn the fan off, turn the knob to the off position.Front Control
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To operate the rear system using the front control, just
turn the knob to the fan position you want.
To use the rear control, rst turn the front control to the
AUX position. Then, the rear control can be used to
increase and decrease the airow.Rear Air Conditioning and Heating
System
If your vehicle is equipped with this system, there are
two rear heat and air conditioning controls. One control
is located in the overhead console and the other is
located in the headliner above the second row seats.
The system can be controlled from the front controls as
well as the rear controls.
The front control has three knobs that control airow
speed, temperature and airow location. Rear Control
Front Control
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Rear Air Conditioning and Heating
System and Electronic Climate
Controls
With this system, the front or rear passengers can
control the air temperature, airow and fan speed for
the rear seat passengers. The climate control has
an overhead control near the driver and a control on
the back of the center console.
Driver Overhead Control
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 airow 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 airow direction, adjust the right knob on
the control panel. Turn the knob clockwise for oor
vent airow or counterclockwise for headliner vent
airow. Generally, the upper vents are used for air
conditioning and the oor vents for heating. The knob
can be set to any blend setting. Choose AUTO if
you want the system to automatically regulate the
airow. See “Auto Mode” later in this section for more
information on using this feature. Front Controls - United States shown,
Canada similar
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