climate control GMC YUKON 2004 User Guide

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 choose
from to clear fog or frost from your windshield. Use
the defog mode to clear the windows of fog or moisture
and warm the passengers. Use the defrost mode to
remove fog or frost from the windshield more quickly.
Turn the right knob clockwise or counterclockwise
to select one of the following modes:
-(Defog):This mode directs the air to the oor
outlets, windshield and the side window vents. The air
conditioning compressor will run automatically to
dehumidify the air to prevent window fogging. The
recirculation mode cannot be selected while in the defog
mode.
1(Defrost):This mode directs most of the air to the
windshield and the side window vents, with only a
little air directed to the oor vents. The air conditioning
compressor will run automatically to dehumidify the
air to prevent window fogging. The recirculation mode
cannot be selected while in defrost mode.
Do not drive the vehicle until all the windows are clear.
Rear Window Defogger
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 automatically turn off
several minutes after the button is pressed. Pressing the
button while the defogger is running can also turn off
the defogger.
If your vehicle is equipped with heated mirrors this
button will activate them.
Notice:Don’t use anything sharp on the inside of
the rear window. If you do, you could cut or damage
the warming grid, and the repairs wouldn’t be
covered by your warranty. Do not attach a temporary
vehicle license, tape, a decal or anything similar
to the defogger grid.
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Dual Automatic Climate Control
System
With this system, you can control the heating, cooling
and ventilation in your vehicle. Your vehicle also
has a ow-through ventilation system described later in
this section.
You can select different climate control settings for the
driver and passengers.
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.
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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.
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.
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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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Fan Knob
The fan knob on the left side of the control panel
adjusts the fan speed. To increase airow, turn the knob
clockwise. To decrease airow, turn it counterclockwise.
To turn the fan off, turn the knob to the off position.
9(Off):An off setting, located on the front climate
control panel also allows the driver to turn off the
rear seat passenger seat controls from the front seat.
Temperature Knob
The middle knob on the control panel lets you select the
temperature of the air owing into the passenger
area. Turn the knob clockwise toward the red area for
warmer air. Turn the knob counterclockwise toward
the blue area for cooler air.
Mode Knob
The right knob on the control panel allows you to
choose the direction of air delivery.
H(Vent):This setting directs the air through the
headliner outlets.
)(Bi-Level):Air is delivered through the oor outlets
as well as the headliner outlets. The ow can be
divided between vent and oor outlets depending upon
where the knob is placed between the settings.
6(Floor):This setting directs most of the air through
the oor outlets.
To use the rear control, rst turn the front control to the
AUX position. Then, the rear control can be used to
adjust the airow speed, temperature, and airow
location.Rear Controls
3-36

Rear Air Conditioning and Heating
System and Electronic Climate
Controls
With this system the front or rear passengers can
control the air temperature, air ow 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
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Rear Passenger Console Control
To control the rear climate control from the rear
passenger seat position, use the rear passenger console
control. The driver overhead control fan knob must be
set to the AUX position.
The rear seat controls have the following settings:
O(On/Off):Press this button to turn the rear seat
comfort controls on or off when the front overhead
control is set to AUX.
%(Mode):Press this button to select the air delivery
mode and AUTO mode. 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.
b(Temperature):Press this button up or down to
increase or decrease the temperature setting.
w9x(Fan):Press this button up or down to adjust
the fan speed. 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.
AUTO Mode
When using the system in auto mode, nd your comfort
setting by placing the temperature control to 74°F
(23°C) and allowing about 20 minutes for the system to
regulate. Then adjust the temperature setting as
necessary. If you choose full cold 60° F (15°C), the
system will remain at the maximum cooling setting. If
you choose full hot 90 F (32°C), the system will remain
at the maximum heat setting. Rear Controls
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Driving with a Trailer
{CAUTION:
If you have a rear-most window open and you
pull a trailer with your vehicle, carbon
monoxide (CO) could come into your vehicle.
You can not see or smell CO. It can cause
unconsciousness or death. SeeEngine
Exhaust on page 2-42. To maximize your safety
when towing a trailer:
Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.
Keep the rear-most windows closed.
If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle. Do not use
the climate control setting for maximum air
because it only recirculates the air inside
your vehicle. SeeClimate Control System
on page 3-22.Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you’ll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the trailer.
And always keep in mind that the vehicle you are
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check all trailer hitch parts and
attachments, safety chains, electrical connector, lamps,
tires and mirror adjustment. If the trailer has electric
brakes, start your vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer
brakes are still working.
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{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim anges could develop cracks after
many miles of driving. A tire and/or wheel
could fail suddenly, causing a crash. Use only
radial-ply tires with the wheels on your vehicle.
Uniform Tire Quality Grading
Quality grades can be found where applicable on the
tire sidewall between tread shoulder and maximum
section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration, which grades tires by
treadwear, traction and temperature performance. (This
applies only to vehicles sold in the United States.)
The grades are molded on the sidewalls of most
passenger car tires.The Uniform Tire Quality Grading system does not
apply to deep tread, winter-type snow tires, space-saver
or temporary use spare tires, tires with nominal rim
diameters of 10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specied government test course.
For example, a tire graded 150 would wear one and
a half (1.5) times as well on the government course as
a tire graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart signicantly from the norm
due to variations in driving habits, service practices and
differences in road characteristics and climate.
5-79

Fuses Usage
4WDFour-Wheel Drive System,
Auxiliary Battery
HTR A/C Climate Control System
LOCKPower Door Lock Relay
(Lock Function)
HVAC 1Inside Rearview Mirror,
Climate Control System
L DOORDriver’s Door Harness
Connection
CRUISE Cruise Control
UNLOCKPower Door Lock Relay
(Unlock Function)
RR FOG LP Rear Fog Lamp (Export Only)
BRAKE Anti-Lock Brake System
DRIVER UNLOCKPower Door Lock Relay
(Driver’s Door Unlock
Function)
IGN 0 PCM, TCM
TBC IGN 0 Truck Body Controller
VEH CHMSLVehicle and Trailer High
Mounted Stoplamp
LT TRLR ST/TRN Left Turn Signal/Stop TrailerFuses Usage
LT TRNLeft Turn Signals and
Sidemarkers
VEH STOPVehicle Stoplamps, Brake
Module, Electronic Throttle
Control Module
RT TRLR ST/TRN Right Turn Signal/Stop Trailer
RT TRNRight Turn Signals and
Sidemarkers
BODY Harness Connector
DDM Driver Door Module
AUX PWR 2Rear Cargo Area Power
Outlets
LOCKS Power Door Lock System
ECCRear Electronic Climate
Control, Liftgate
TBC 2C Truck Body Controller
FLASH Flasher Module
CB LT DOORSLeft Power Window Circuit
Breaker
TBC 2B Truck Body Controller
TBC 2A Truck Body Controller
5-115