
Black plate (4,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
8-4 Climate Controls
Dual Automatic Climate Control System
The heating, cooling, and ventilation in the vehicle can be controlled with
this system. The vehicle also has a flow-through ventilation system
described later in this section.
If the vehicle is a hybrid, see the hybrid supplement for more information.
A. Fan Control
B. AUTO (Automatic Operation)
C. Defrost
D. RecirculationE. REAR (Rear Climate Control)
F. Air Delivery Mode Control
G. Driver Temperature Control
H. DisplayI. Power Button
J. Rear Window Defogger
K. Air Conditioning
L. PASS
M. Passenger Temperature Control
O(On/Off):
Press to turn the
climate control system on or off.
Outside air still enters the vehicle,
and is directed to the floor. 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 the air delivery mode or
temperature settings are adjusted
with the system off, the display
illuminates briefly to show the
settings and then returns to off. The
system can be turned back on by
pressing either
O,D,C,#, the
defrost or the AUTO button.

Black plate (5,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
Climate Controls 8-5
Driver and Passenger Side
Temperature Control
The driver and passenger side
temperature buttons are used to
adjust the temperature of the air
coming through the system on the
driver or passenger side of the
vehicle. The temperature can be
adjusted even if the system is
turned off. This is possible since
outside air always flows through the
system as the vehicle is moving
forward unless it is set to
recirculation mode. See
“Recirculation”later in this section.
Press the + or −buttons to increase
or decrease the cabin temperature.
The driver side or passenger side
temperature display shows the
temperature setting decreasing or
increasing.
The passenger temperature setting
can be set to match the driver
temperature setting by pressing the
PASS button and turning off the
PASS indicator. When in defrost mode the
passenger temperature setting
cannot be changed.
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 4°C (40°F). The air inlet will normally be set to outside
air. If it is hot outside, the air
inlet may automatically switch to
recirculate inside air to help
quickly cool down the vehicle.
The light on the button comes on
in recirculation.
2. Set the driver and passenger temperature.
To find your comfort setting, start
with a 23°C (74°F) temperature
setting and allow about
20 minutes for the system to
regulate. Use the driver or
passenger temperature buttons
to adjust the temperature setting
as necessary. If a temperature
setting of 15°C (60°F) is chosen,
the system remains at the
maximum cooling setting. If a
temperature setting of 32°C
(90°F) is chosen, the system
remains at the maximum heat
setting. Choosing either
maximum setting will not cause
the vehicle to heat or cool any
faster.

Black plate (6,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
8-6 Climate Controls
Do not cover the solar 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 the headlamps. For more
information on the solar sensor, see
“Sensors”later in this section.
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.
Manual Operation
D C(Fan Control): Press these
buttons to increase or decrease the
fan speed.
Pressing either fan button while in
automatic control places the fan
under manual control. The fan
setting remains displayed and the
AUTO light turns off. The air
delivery mode remains under
automatic control.
H G(Air Delivery Mode Control):
Press these buttons to change the
direction of the airflow in the vehicle.
Repeatedly press either button until
the desired mode appears on the
display. Pressing either mode button
while the system is off changes the
air delivery mode without turning the
system on. Pressing either mode
button while in automatic control
places the mode under manual
control.
The air delivery mode setting is
displayed and the AUTO light turns
off. The fan remains under
automatic control.
H(Vent): Air is directed to the
instrument panel outlets.
)(Bi-Level): Air is divided
between the instrument panel and
floor outlets. Some air is directed
towards the windshield and side
window outlets.
6(Floor): Air is directed to the
floor outlets, with some to the
windshield, side window outlets, and second row floor outlets. In this
mode, the system automatically
selects outside air.
-(Defog):
This mode clears the
windows of fog or moisture. Air is
directed to the windshield, floor
outlets, and side window vents. In
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.
0(Defrost): This mode removes
fog or frost from the windshield
more quickly. Air is directed to the
windshield and side window vents,
with some directed to the floor
vents. In this mode, the system
automatically forces outside air into
the vehicle and runs the air
conditioning compressor unless the
outside temperature is close to
freezing. The recirculation mode
cannot be selected while in the
defrost mode.

Black plate (7,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
Climate Controls 8-7
The passenger temperature control
cannot be activated while in defrost
mode. If the PASS button is
pressed, the button indicator flashes
three times and will not work. If the
passenger temperature buttons are
adjusted, the driver temperature
indicator changes. The passenger
temperature will not be displayed.
If vent, bi-level, or floor mode is
selected again, the climate control
system displays the previous
temperature settings.
Do not drive the vehicle until all the
windows are clear.
#(Air Conditioning):Press to
turn the air conditioning (A/C)
compressor on and off. An indicator
light comes on to show that the air
conditioning is on. If this button is pressed when the air
conditioning compressor is
unavailable, the indicator flashes
three times and then turns off. 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 turns off to show
that 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 the vehicle to cool down.
It also helps the system to operate
more efficiently.
The air conditioning system
removes moisture from the air, so a
small amount of water might drip
under the vehicle while idling or
after turning off the engine. This is
normal.
@(Recirculation):
Press to turn
the recirculation mode on or off. An
indicator light comes on to show
that the recirculation is on.
This mode recirculates and helps to
quickly cool the air inside the
vehicle. It can be used to help
prevent outside air and odors from
entering the vehicle.
The recirculation mode cannot be
used with floor, defog, or defrost
modes. If recirculation is selected
with one of those modes, the
indicator light flashes three times
and then turns off. The air
conditioning compressor also comes
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.
The recirculation mode can also be
turned off by turning off the ignition.

Black plate (8,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
8-8 Climate Controls
PASS:Press to set the passenger
temperature setting to match the
driver temperature setting. The
PASS indicator will turn off. When
the passenger temperature setting
is set different than the driver
setting, the indicator on the PASS
button illuminates and both the
driver side and passenger side
temperature displays are shown.
REAR: For vehicles with the rear
heat and air conditioning controls.
Press to turn the rear climate control
system on or off. See Rear Climate
Control System (Rear Climate
Control Only) on page 8‑10 orRear
Climate Control System (Rear
Climate with Rear Seat Audio) on
page 8‑11.Rear Window Defogger
The rear window defogger uses a
warming grid to remove fog from the
rear window.
1(Rear Window Defogger):
Press to turn the rear window
defogger on or off. It automatically
turns off several minutes after it has
been activated. The defogger can
also be turned off by turning off the
engine. Do not drive the vehicle until
all the windows are clear. 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.
Heated Mirrors: Press
1to help
clear fog or frost from the surface of
the outside mirror. See Power
Mirrors on page 2‑17.

Black plate (11,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
Climate Controls 8-11
)(Bi-Level):Air is directed
through the floor and 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): Air is directed to the
floor outlets. The rear system floor
outlets are located directly behind
the second row seats.
Rear Climate Control System (Rear Climate with Rear
Seat Audio)
For vehicles with the rear heat and air conditioning controls, they 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.
Rear Climate Control with Rear Seat Audio Controls
A. Fan Control
B. Air Delivery Mode Control
C. Temperature Control REAR:
Press the REAR button on
the front climate control system to
turn the rear climate control system
on or off. An indicator comes on
when the rear system is on.

Black plate (13,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
Climate Controls 8-13
Air Vents
Use the air outlets located in the
center and on the side of the
instrument panel to direct the
airflow.
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 the 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
the window.
.Keep the air path under the front
seats clear of objects. This helps
air to circulate throughout the
vehicle.
.Adding outside equipment to the
front of the vehicle, such as
hood-air deflectors, may affect
the performance of the heating
and air conditioning system.
Check with your dealer before
adding equipment to the outside
of the vehicle.

Black plate (20,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
10-20 Vehicle Care
.Tows a trailer. SeeTrailer
Towing on page 9‑66.
If the overheat warning is displayed
with no sign of steam:
1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest
fan speed. Open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral) while stopped.
If it is safe to do so, pull off the
road, shift to P (Park) or
N (Neutral) and let the
engine idle.
If the temperature overheat gauge is
no longer in the overheat zone or an
overheat warning no longer
displays, the vehicle can be driven.
Continue to drive the vehicle slowly
for about 10 minutes. Keep a safe
vehicle distance from the vehicle in
front. If the warning does not come
back on, continue to drive normally. If the warning continues, pull over,
stop, and park the vehicle
right away.
If there is no sign of steam, idle the
engine for three minutes while
parked. If the warning is still
displayed, turn off the engine until it
cools down. Also, see
“Overheated
Engine Protection Operating Mode”
later in this section.
Overheated Engine
Protection
Operating Mode
If an overheated engine condition
exists and the ENGINE POWER IS
REDUCED message is displayed,
an overheat protection mode which
alternates firing groups of cylinders
helps prevent engine damage. In
this mode, a loss in power and
engine performance will be noticed.
This operating mode allows the
vehicle to be driven to a safe place
in an emergency. Driving extended distances and/or towing a trailer in
the overheat protection mode
should be avoided.
Notice:
After driving in the
overheated engine protection
operating mode, to avoid engine
damage, allow the engine to cool
before attempting any repair. The
engine oil will be severely
degraded. Repair the cause of
coolant loss, change the oil and
reset the oil life system. See
Engine Oil on page 10‑6.
Engine Fan
If the vehicle has a clutched engine
cooling fan, when the clutch is
engaged, the fan spins faster to
provide more air to cool the engine.
In most everyday driving conditions,
the fan is spinning slower and the
clutch is not fully engaged. This
improves fuel economy and reduces
fan noise. Under heavy vehicle
loading, trailer towing, and/or high
outside temperatures, the fan speed
increases as the clutch more fully