2012 GMC YUKON climate control

Black plate (38,1)GMC Yukon/Yukon XL Owner Manual - 2012
5-38 Instruments and Controls
Battery Voltage and
Charging Messages
BATTERY LOW START
VEHICLE
When the vehicle’s battery is
severely discharged, this message
will display and four chimes will
sound. Start the vehicle
immediately. If the vehicle is not
started and the battery continues to
discharge, the climate controls,
heated seats, and audio systems
will shut off and the vehicle may
require a jump start. These systems
will function again after the vehicle
is started.
SERVICE BATTERY
CHARGING SYSTEM
On some vehicles, this message
displays if there is a problem with
the battery charging system. Under
certain conditions, the charging
system light may also turn on in the
instrument panel cluster. See
Charging System Light on
page 5‑20. Driving with this problem could drain the battery. Turn off all
unnecessary accessories. Have the
electrical system checked as soon
as possible. See your dealer.
Brake System Messages
SERVICE BRAKE SYSTEM
This message displays along with
the brake system warning light if
there is a problem with the brake
system. See
Brake System Warning
Light on page 5‑23. If this message
appears, stop as soon as possible
and turn off the vehicle. Restart the
vehicle and check for the message
on the DIC display. If the message
is still displayed or appears again
when you begin driving, the brake
system needs service as soon as
possible. See your dealer.
SERVICE BRAKES SOON
This message displays if there is a
problem with the brake system.
If this message appears, stop as
soon as possible and turn off the
vehicle. Restart the vehicle and check for the message on the DIC
display. If the message is still
displayed or appears again when
you begin driving, the brake system
needs service. See your dealer.
SERVICE TRAILER BRAKE
SYSTEM
On vehicles with the Integrated
Trailer Brake Control (ITBC) system,
this message displays and a chime
sounds when there is a problem
with the ITBC system.
When this message displays, power
is no longer available to the trailer
brakes.
As soon as it is safe to do so,
carefully pull your vehicle over to
the side of the road and turn the
ignition off. Check the wiring
connection to the trailer and turn the
ignition back on. If this message still
displays, either your vehicle or the
trailer needs service. See your
dealer.

Black plate (10,1)GMC Yukon/Yukon XL Owner Manual - 2012
6-10 Lighting
The battery can be discharged at
idle if the electrical loads are very
high. This is true for all vehicles.
This is because the generator
(alternator) may not be spinning fast
enough at idle to produce all the
power that is needed for very high
electrical loads.
A high electrical load occurs when
several of the following are on, such
as: headlamps, high beams, fog
lamps, rear window defogger,
climate control fan at high speed,
heated seats, engine cooling fans,
trailer loads, and loads plugged into
accessory power outlets.
EPM works to prevent excessive
discharge of the battery. It does this
by balancing the generator's output
and the vehicle's electrical needs.
It can increase engine idle speed to
generate more power, whenever
needed. It can temporarily reduce
the power demands of some
accessories.Normally, these actions occur in
steps or levels, without being
noticeable. In rare cases at the
highest levels of corrective action,
this action may be noticeable to the
driver. If so, a Driver Information
Center (DIC) message might be
displayed, such as BATTERY LOW
START VEHICLE. If this message
displays, it is recommended that the
driver reduce the electrical loads as
much as possible and restart the
vehicle. See
Battery Voltage and
Charging Messages on page 5‑38.Battery Power Protection
This feature shuts off the dome, and
reading lamps if they are left on for
more than 10 minutes when the
ignition is off. This will keep the
battery from running down.

Black plate (1,1)GMC Yukon/Yukon XL Owner Manual - 2012
Climate Controls 8-1
Climate Controls
Climate Control Systems
Climate Control Systems . . . . . . 8-1
Dual Automatic Climate ControlSystem . . . . . . . . . . . . . . . . . . . . . . 8-4
Rear Climate Control System (Rear Climate
Control Only) . . . . . . . . . . . . . . . 8-10
Rear Climate Control System (Rear Climate with Rear Seat
Audio) . . . . . . . . . . . . . . . . . . . . . . 8-11
Air Vents
Air Vents . . . . . . . . . . . . . . . . . . . . . 8-13
Climate Control Systems
The heating, cooling, and ventilation in the vehicle can be controlled with
this system.
A. Fan Control
B. REAR (Rear Climate Control)
C. Recirculation
D. Air Delivery Mode Control
E. Air Conditioning F. Driver and Passenger
Temperature Controls
G. Rear Window Defogger
Temperature Control: Move the
thumbwheels up or down to
increase or decrease the
temperature on the driver side or
the passenger side of the vehicle for
the dual zone system.

Black plate (2,1)GMC Yukon/Yukon XL Owner Manual - 2012
8-2 Climate Controls
9(Fan Control):Turn the left
knob clockwise or counterclockwise
to increase or decrease the fan
speed. Turn the knob all the way
counterclockwise to turn the front
system off.
Air Delivery Mode Control: Turn
clockwise or counterclockwise to
change the airflow direction inside
the vehicle. By positioning the knob
between two modes, a combination
of those modes is selected.
Select from the following modes:
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. Cooler air is
directed to the upper outlets and
warmer air to the floor outlets.
6(Floor): Air is directed to the
floor outlets, with some of the air
directed to the windshield, side window, and second row floor
outlets. In this mode, the system
automatically selects outside air.
Recirculation cannot be selected
when in Floor Mode.
-(Defog):
The defog mode is
used to clear 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): The defrost mode is
used to remove 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. The recirculation
mode cannot be selected while
in the defrost mode. The air
conditioning compressor runs automatically in this setting, unless
the outside temperature is close to
freezing.
Do not drive the vehicle until all the
windows are clear.
#(Air Conditioning):
Press this
button to turn the air conditioning
system on or off. An indicator light
comes on to show that the air
conditioning is on. The air
conditioning can be selected in
any mode as long as the fan
switch is on.
On hot days, open the windows to
let hot inside air escape; then close
them. 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.

Black plate (3,1)GMC Yukon/Yukon XL Owner Manual - 2012
Climate Controls 8-3
h(Recirculation):Press this
button to turn the recirculation mode
on or off. An indicator light comes
on to show that 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, defrost, or defogging
modes. If recirculation is selected
while in one of those modes, the
indicator flashes three times and
turns 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. The
recirculation mode can also be
turned off by turning off the engine. REAR:
Press to turn the rear
heating and air conditioning on. See
Rear Climate Control System (Rear
Climate Control Only) on page 8‑10
or Rear Climate Control System
(Rear Climate with Rear Seat Audio)
on page 8‑11 for more information.
Rear Window Defogger
The rear window defogger uses a
warming grid to remove fog from the
rear window.
1(Rear Window Defogger):
Press this button to turn the rear
window defogger on or off. The
system 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. For vehicles with 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 anything
sharp on the inside of the rear
window. If you do, you could cut
or damage the warming grid, and
the repairs would not be covered
by the vehicle warranty. Do not
attach a temporary vehicle
license, tape, a decal, or anything
similar to the defogger grid.

Black plate (4,1)GMC Yukon/Yukon XL Owner Manual - 2012
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. Recirculation
E. REAR (Rear Climate Control)F. Air Delivery Mode Control
G. Driver Temperature Control
H. Display
I. Power Button
J. Rear Window DefoggerK. 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 - 2012
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,

Black plate (6,1)GMC Yukon/Yukon XL Owner Manual - 2012
8-6 Climate Controls
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.
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.