2009 GMC YUKON air conditioning

6(Floor):Air is directed to the oor outlets, with
some to the windshield, side window outlets, and second
row oor 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, oor 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 oor
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.
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 ashes
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.
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@(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 oor, defog,
or defrost modes. If recirculation is selected with one
of those modes, the indicator light ashes 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.
REAR:For vehicles with the rear heat and air
conditioning controls. Press to turn the rear climate
control system on or off. SeeRear Air Conditioning and
Heating System and Electronic Climate Controls on
page 3-33.Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog from the rear window.
<(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:For vehicles with heated outside
rearview mirrors, the mirrors heat to help clear fog or
frost from the surface of the mirror when the rear window
defog button is pressed. SeeOutside Power Mirrors
on page 2-50.
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Outlet Adjustment
Use the air outlets located in the center and on the side
of the 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 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 deectors, may affect the
performance of the heating and air conditioning
system. Check with your dealer/retailer before
adding equipment to the outside of the vehicle.
Rear Air Conditioning and Heating
System
For vehicles with this system, the rear controls are three
knobs located in the headliner. The system can also
be controlled with the front controls.
A. Fan Control
B. Temperature Control
C. Air Delivery Mode Control
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Rear Air Conditioning and Heating
System and Electronic Climate
Controls
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.
A. Fan Control
B. Air Delivery Mode Control
C. Temperature ControlREAR: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.
The rear climate control system can also be turned off by
pressing and holding theCbutton. To turn the system on
from the rear seats, press any rear climate control button,
except the
Cbutton.
Mimic Mode:This mode matches the rear climate
control to the front climate control airow settings.
It comes on when REAR is pressed the rst time.
Independent Mode:This mode directs rear seating
airow according to the settings of the rear controls.
To turn the system on from the rear, press any
rear climate control button, except the
Cbutton.
Rear Climate Control with Rear Seat Audio Controls
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CHECK TRAILER WIRING
On vehicles with the Integrated Trailer Brake Control
(ITBC) system, this message may display and a chime
may sound when one of the following conditions exists:
A trailer with electric brakes becomes disconnected
from the vehicle.
If the disconnect occurs while the vehicle is
stopped, this message clears itself after a short
time.
If the disconnect occurs while the vehicle is
moving, this message stays on until the ignition
is turned off.
There is a short in the wiring to the electric trailer
brakes.
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. This message clears if the trailer is
reconnected. This message also clears if you
acknowledge it. If this message still displays, either
your vehicle or the trailer needs service. See your
dealer/retailer.
See “Integrated Trailer Brake Control System” under
Towing a Trailer on page 4-52for more information.
DRIVER DOOR OPEN
This message displays and a chime sounds if the driver
door is not fully closed and the vehicle is shifted out
of P (Park). Stop and turn off the vehicle, check the door
for obstructions, and close the door again. Check to
see if the message still appears on the DIC.
ENGINE HOT A/C (Air Conditioning)
TURNED OFF
This message displays when the engine coolant
becomes hotter than the normal operating temperature.
SeeEngine Coolant Temperature Gage on page 3-43.
To avoid added strain on a hot engine, the air
conditioning compressor automatically turns off. When
the coolant temperature returns to normal, the air
conditioning compressor turns back on. You can
continue to drive your vehicle.
If this message continues to appear, have the system
repaired by your dealer/retailer as soon as possible
to avoid damage to the engine.
ENGINE OIL HOT IDLE ENGINE
This message displays when the engine oil becomes
hotter than the normal operating temperature. Stop and
allow the vehicle to idle until it cools down. See
Engine Coolant Temperature Gage on page 3-43.
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Engine Fan Noise
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 engages, so you may hear an
increase in fan noise. This is normal and should not be
mistaken as the transmission slipping or making extra
shifts. It is merely the cooling system functioning properly.
The fan will slow down when additional cooling is not
required and the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch partially
disengages.
If the vehicle has electric cooling fans, you may hear the
fans spinning at low speed during most everyday driving.
The fans may turn off if no cooling is required. Under
heavy vehicle loading, trailer towing, and/or high outside
temperatures, or if you are operating the air conditioning
system, the fans may change to high speed and you
may hear an increase in fan noise. This is normal and
indicates that the cooling system is functioning properly.
The fans will change to low speed when additional
cooling is no longer required.
Power Steering Fluid
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
SeeEngine Compartment
Overview on page 5-14for
reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power steering uid
unless you suspect there is a leak in the system or
you hear an unusual noise. A uid loss in this system
could indicate a problem. Have the system inspected
and repaired.
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(A) Light Truck (LT-Metric) Tire:The United
States version of a metric tire sizing system.
The letters LT as the rst two characters in the
tire size means a light truck tire engineered to
standards set by the U.S. Tire and Rim Association.
(B) Tire Width
:The three-digit number indicates
the tire section width in millimeters from sidewall to
sidewall.
(C) Aspect Ratio
:A two-digit number that
indicates the tire height-to-width measurements.
For example, if the tire size aspect ratio is 75, as
shown in item C of the light truck (LT-Metric) tire
illustration, it would mean that the tire’s sidewall is
75 percent as high as it is wide.
(D) Construction Code
:A letter code is used to
indicate the type of ply construction in the tire. The
letter R means radial ply construction; the letter D
means diagonal or bias ply construction; and the
letter B means belted-bias ply construction.(E) Rim Diameter
:Diameter of the wheel in
inches.
(F) Service Description
:The service description
indicates the load range and speed rating of a
tire. The load index represents the load carry
capacity a tire is certied to carry. The load index
can range from 1 to 279. The speed rating is
the maximum speed a tire is certied to carry a
load. Speed ratings range from A to Z.
Tire Terminology and Denitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
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Fuses Usage
7 Front Washer
8 Oxygen Sensors
9 Antilock Brakes System 2
10 Trailer Back-up Lamps
11 Driver Side Low-Beam Headlamp
12 Engine Control Module (Battery)
13Fuel Injectors, Ignition Coils
(Right Side)
14Transmission Control Module
(Battery)
15 Vehicle Back-up Lamps
16Passenger Side Low-Beam
Headlamp
17 Air Conditioning Compressor
18 Oxygen Sensors
19 Transmission Controls (Ignition)
20 Fuel Pump
21 Fuel System Control Module
22 Headlamp Washers
23 Rear Windshield Washer
24Fuel Injectors, Ignition Coils
(Left Side)
25 Trailer Park Lamps
26 Driver Park LampsFuses Usage
27 Passenger Side Park Lamps
28 Fog Lamps
29 Horn
30Passenger Side High-Beam
Headlamp
31 Daytime Running Lamps
32 Driver Side High-Beam Headlamps
33 Daytime Running Lamps 2
34 Sunroof
35Key Ignition System, Theft Deterrent
System
36 Windshield Wiper
37 SEO B2 Uptter Usage (Battery)
38 Electric Adjustable Pedals
39 Climate Controls (Battery)
40 Airbag System (Ignition)
41 Amplier
42 Audio System
43Miscellaneous (Ignition), Cruise
Control
44 Liftgate Release
45 Airbag System (Battery)
46 Instrument Panel Cluster
47 Not Used
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