2002 GMC YUKON XL heating

2-12Liftgate/Liftgate Glass
CAUTION:It can be dangerous to drive with the liftgate or
liftgate glass open because carbon monoxide
(CO) gas can come into your vehicle. You can't
see or smell CO. It can cause unconsciousness
and even death.
If you must drive with the liftgate or liftgate
glass open or if electrical wiring or other cable
connections must pass through the seal between
the body and the liftgate or liftgate glass:

Make sure all other windows are shut.

Turn the fan on your heating or cooling
system to its highest speed with the setting
on VENT or OUTSIDE AIR. That will
force outside air into your vehicle. See
ªComfort Controlsº in the Index.

If you have air outlets on or under the
instrument panel, open them all the way.
See ªEngine Exhaustº in the Index. To open from the outside, insert the key into the
lock and turn it counterclockwise to unlock the glass
and liftgate.
The liftgate glass can be opened using the pushbutton on
the liftgate after the doors have been unlocked. This can
be done by using either the power door locks or the
remote keyless entry system.
To open the entire liftgate, lift the handle located in the
center of the door.
To lock from the outside, insert the key into the lock
button and turn clockwise. All doors will lock. You may
also use the remote keyless entry system or the power
door locks to lock the liftgate and liftgate glass.
Theft Vehicle theft is big business, especially in some cities.
Although your vehicle has a number of theft
- deterrent
features, we know that nothing we put on it can make
it impossible to steal. However, there are ways you
can help.

2-52Ashtrays and Cigarette Lighter The front ashtray is located in the center console. Press
the raised area on the access door to use the ashtray.
NOTICE: If you store paper or other things that burn in
your ashtrays, they could be set on fire by
cigarettes or other smoking materials. That could
cause a fire and possibly damage your vehicle.
Do not store papers and other things that burn
in your ashtrays.
To remove the ashtray first locate the indent on the right
side of the ashtray. Then, place the tip of your finger in
the indent and pry the ashtray out.
To use the cigarette lighter, push it in all the way, and let
go. When it's ready, it will pop back out by itself. NOTICE: Holding a cigarette lighter in with your hand
while it's heating can make it overload, damaging
the lighter and the heating element. Just push the
lighter all the way in and let go. When it's done,
it will pop back out by itself.
Sun Visors To block out glare, you can swing down the visors.
You can also swing them out to help block glare at
the front and side windows.
Illuminated Visor Vanity Mirrors Pull the sunvisor down and lift the mirror cover to turn
on the lamps. There is a switch to adjust the intensity
of the lamps.

2-70Engine Coolant Temperature Gage
United States Canada
This gage shows the engine coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210
F (100
C) or less. If you are pulling a
load or going up hills, it is normal for the temperature to
fluctuate and approach the 250
F (122
C) mark. If the
gage reaches the 260
F (125
C) mark, it indicates that
the cooling system is working beyond its capacity.
The ªProblems on the Road,º section of this manual
shows what to do. See ªEngine Overheatingº in
the Index. Transmission Temperature Gage
United States Canada
When your ignition is on, the gage shows the
temperature of the transmission fluid. The normal
operating range is from 100
F (38
C) to about
265
F (130
C).
At approximately 265
F (130
C), the message center
will display a TRANS FLUID HOT message and the
transmission will enter a transmission protection mode.
When the transmission enters the protection mode, you
may notice a change in the transmission shifting
patterns. The transmission will return to normal shifting
patterns when the transmission fluid temperature falls
below 260
F (127
C).

2-80Low Coolant This message is displayed
when the cooling system is
low on coolant.
The engine may overheat. See ªEngine Coolantº in
the Index and have your vehicle serviced as soon as
you can.
Check Coolant Temp This message is displayed
when the cooling system
temperature gets hot.
Check the coolant temperature gage and the coolant
level. See ªEngine Coolant,º ªEngine Coolant
Temperature Gageº and ªEngine Overheatingº in the
Index for further information. Engine Overheated This message is displayed
when the cooling system
temperature gets too hot.
This message will be displayed after the air conditioning
system has automatically turned off for the engine
coolant protection mode. See ªEngine Overheatingº in
the Index for further information.
Reduced Engine Power This message is displayed
when the cooling system
temperature gets too hot
and the engine further
enters the engine coolant
protection mode.
See ªEngine Overheatingº in the Index for
further information.

3-
3-1Section 3 Comfort Controls and Audio SystemsIn this section, you'll find out how to operate the comfort control and audio systems offered with your vehicle.
Be sure to read about the particular systems supplied with your vehicle.
3
- 2 Comfort Controls
3
- 2 Electronic Climate Control System
3
- 8 Air Conditioning
3
- 8 Heating
3
- 9 Defogging and Defrosting
3
- 9 Rear Window Defogger
3
- 10 Ventilation System
3
- 11 Audio Systems
3
- 11 Setting the Clock
3
- 12 AM
- FM Stereo with Cassette Tape
Player (Bose

) 3
- 17 Rear Seat Audio (RSA)
3
- 19 Compact Disc Changer
3
- 22 Theft
- Deterrent Feature
3
- 24 Audio Steering Wheel Controls
3
- 25 Understanding Radio Reception
3
- 25 Tips About Your Audio System
3
- 26 Care of Your Cassette Tape Player
3
- 27 Care of Your Compact Discs
3
- 27 Care of Your Compact Disc Player
3
- 27 Fixed Mast Antenna

3-2Comfort Controls Electronic Climate Control System
Fan Knob
The knob on the left side of the electronic climate
control panel regulates the fan speed. To manually
increase airflow, turn the knob clockwise. To manually
decrease airflow, turn it counterclockwise.
OFF: If the knob is in OFF, outside air will still enter
the vehicle, and will be directed based on the position of
the mode knob. AUTO (Automatic): If the knob is in AUTO, the
fan speed will vary as the system maintains the
selected temperature.
When both the fan knob and mode knobs are in the
AUTO position, the system will then automatically
maintain the desired cabin temperature selected.
Manual operation is also available.
Temperature Knob
The middle knob on the control panel lets you select the
desired air temperature in your vehicle. Turn the knob
clockwise toward 82 for warmer air. Turn the knob
counterclockwise toward 66 for cooler air. When the
system is set for automatic operation, sensors will
regulate the fan speed.
(Full hot): If you turn the temperature knob past 82
F
(28
C), the system will go into the ªfull hotº mode.
The system will remain at that maximum heating setting
and the fan will blow at the speed to which the fan knob
is set. If the fan is in AUTO, it will run at full speed.
(Full cold): If you turn the temperature knob past 66
F
(19
C), the system will go into the ªfull coldº mode.
The system will remain at that maximum cooling setting
and the fan will blow at the speed to which the fan knob
is set. If the fan is in AUTO, it will run at full speed.

3-6Rear Air Conditioning and Rear Heater
(With Sunroof) Your vehicle has the rear air conditioning and rear
heater system combination. Controls are provided to
regulate the temperature, the air delivery location and
the fan speed.
Front Control To adjust the fan speed, turn the fan knob located on the
left side to the desired setting.
To select the direction of airflow turn the right knob
located on the control panel to the desired setting.
Generally, the upper vents are used for air conditioning
and the floor vents for heating. The knob can be set to
any blend setting.
To adjust the air temperature, turn the temperature knob
on the center of the control panel to the desired setting.
For warmer air, turn the knob clockwise toward red. For
cooler air, turn the knob counterclockwise toward blue.

3-7Rear Air Conditioning and Heating Systems
with Electronic Climate Control System
(Without Sunroof)
Front Control
Rear Control With this system the rear passengers can control the
temperature of the air flow for the rear seating area.
The climate control panels have three knobs.
To adjust the fan speed, turn the fan knob located on
the left side of the control panel to the desired setting.
The system also has a front AUTO setting that can
automatically change the temperature of the rear seating
area based on information received from the front
control panel. The OFF setting, located on the front
climate control panel, also allows the driver to turn off
the rear passenger seat controls from the front seat.
To adjust the air temperature, turn the temperature knob
located on the center of the control panel clockwise
toward 82
F (28
C) for warmer air and
counterclockwise toward 66
F (19
C) for cooler air.
To direct the airflow, turn the right knob located on
the control panel clockwise or counterclockwise to the
desired mode. Generally, the upper vents are used for air
conditioning and the floor vents for heating. The control
knob can be set to any blend setting.
For rear control operation, use the above instructions.