2008 HUMMER H3 air conditioning

Ashtray(s) and Cigarette Lighter
Your vehicle may have an ashtray and cigarette lighter.
Your ashtray is located in your center console area.
The ashtray can be removed for cleaning. When
the ashtray is removed, this area can also be used as a
cupholder.
Notice:If you put papers, pins, or other ammable
items in the ashtray, hot cigarettes or other
smoking materials could ignite them and possibly
damage your vehicle. Never put ammable items in
the ashtray.
To use the lighter, press 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 while it is
heating does not let the lighter back away from the
heating element when it is hot. Damage from
overheating can occur to the lighter or heating
element, or a fuse could be blown. Do not hold a
cigarette lighter in while it is heating.
Climate Controls
Climate Control System
The heating, cooling, and ventilation of the vehicle can
be controlled with this system.
Temperature:Turn the left knob on the control panel to
adjust the temperature of the air in the vehicle. Turn
the knob clockwise or counterclockwise to increase or
decrease the temperature.
#(Air Conditioning):Press the center of the left
knob on the control panel to turn the air conditioning
system on or off. An indicator light on the button will be
lit when the air conditioning is turned on. This system
cools and dehumidies the air entering the vehicle.
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The air conditioning will not function if the fan is turned
off. If air conditioning is selected with fan off, the
indicator light ashes three times and then turns off.
A slight change in engine performance may occur when
the air conditioning compressor shuts off and turns
on again. This is normal. The system is designed
to make adjustments to help with fuel economy while
still maintaining the selected temperature.
The air conditioning system removes moisture from the
air, so sometimes there may be a small amount of
water dripping underneath the vehicle while idling or
after turning off the engine. This is normal.
9(Fan):Turn the center knob on the control panel to
control the fan speed. Turn the knob clockwise or
counterclockwise to increase or decrease the fan speed.
9(Off):Turn the center knob to this position to turn
the fan off. With the fan off, you may still experience
airow from the system that increases with vehicle
speed depending on the mode and temperature settings.
Enable recirculation mode to stop this airow from
occurring.
@(Recirculation):Press the center of the fan
control knob to recirculate air inside the vehicle and
prevent outside air from coming in. It can be used
to prevent outside odors from entering the vehicle and
cool the air inside the vehicle more quickly. Pressthis button to turn the recirculation mode on or off. An
indicator light on the button comes on to show that
the recirculation mode is activated.
Recirculation is available in the bi-level, and vent
modes. Recirculation is not available while in oor,
oor/defog and defrost mode. If recirculation is selected
in these modes, the indicator ashes three times
indicating it is not available in that mode. When the
recirculation mode is turned on, the air conditioning turns
on automatically.
When it is hot enough outside, the recirculation mode
may turn on automatically to help improve cooling
performance. The indicator light will be lit to show this
mode is active. If the recirculation button is pressed
while in this mode, the light will ash three times
and stay on to indicate that recirculation may not be
shut off.
The right knob on the control panel is used to direct the
airow inside the vehicle. In-between modes are
available by moving the right control knob between
modes with symbols. The in-between mode is a
combination of the two modes that the control is
centered between.
Turn the right knob to select one of the following modes:
H(Vent):This mode directs air to the instrument
panel outlets.
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\(Bi-Level):This mode directs air to the instrument
panel outlets, and the remaining air to the oor
outlets and the defroster and side window outlets.
Cooler air is directed to the upper outlets and warmer
air to the oor outlets.
[(Floor):This mode directs air to the oor outlets,
side window outlets, and defroster. Recirculation is
not available in this mode.
Defogging and Defrosting
Fog on the inside of 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 clear fog or frost from
the windshield and side windows. 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. For best results, clear
all snow and ice from the windshield before defrosting.
/(Floor/Defog):This mode directs the air to the
windshield, the side window outlets, and to the
oor outlets. When this mode is selected, the system
runs the air conditioning system unless the outside
temperature is near freezing or below. Recirculation is
not available in this mode.
0(Defrost):This mode directs most of the air to the
windshield, and the side window outlets. When this
mode is selected, the system runs the air conditioning
system unless the outside temperature is near or below
freezing. Recirculation is not available in this mode.
Do not drive the vehicle until all the windows are clear.
Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog or frost from the rear window when the key
is in the ignition and turned to ON/RUN.
=(Rear Defogger):Press the center of the right
knob on the control panel to turn the rear window
defogger on or off. First press of this button activates
the rear window defogger for 15 minutes and each
subsequent activation lasts seven and one-half minutes.
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 your warranty. Do not attach a temporary
vehicle license, tape, a decal or anything similar to
the defogger grid.
Outlet Adjustment
Use the air outlets located in the center and on the side
of your instrument panel to direct the airow.
Your vehicle has air outlets that allow you to adjust the
direction and amount of airow inside the vehicle.
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Move the louvers up or down to change the direction of
the airow. Use the thumbwheel under the outlets to
change the direction of the airow from left to right.
Operation Tips

Enable recirculation mode for maximum air
conditioning performance.
Clear away any ice, snow or leaves from the air
inlets at the base of the windshield that may
block the ow of air into your vehicle.
Use of non-GM approved hood deectors may
adversely affect the performance of the system.
Keep the path under the front seats clear of objects
to help circulate the air inside of your vehicle more
effectively.
Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages on
your vehicle. The pictures help to locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause an
expensive repair or replacement. Paying attention to the
warning lights and gages could also save you or others
from injury.Warning lights come on when there may be or is a
problem with one of your vehicle’s functions. As the
details show on the next few pages, some warning lights
come on briey when you start the engine just to let you
know they are working. If you are familiar with this
section, you should not be alarmed when this happens.
Gages can indicate when there may be or is a problem
with one of your vehicle’s functions. Often gages and
warning lights work together to let you know when there is
a problem with your vehicle.
When one of the warning lights comes on and stays on as
you are driving, or when one of the gages shows there
may be a problem, check the section that tells you what
to do about it. Please follow this manual’s advice. Waiting
to do repairs can be costly and even dangerous. So
please get to know your vehicle’s warning lights and
gages. They can be a big help.
Your vehicle may also have a Driver Information Center
(DIC) that works along with the warning lights and gages.
SeeDriver Information Center (DIC) on page 3-40for
more information.
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AC (Air Conditioning) OFF
This message displays when the engine coolant
temperature is too high and the air conditioning in your
vehicle needs to be turned off. SeeEngine Overheating
on page 5-29andClimate Control System on
page 3-22for more information. This message displays
along with the ENG HOT message.
ABS (Antilock Brake System) FAULT
This message displays if there is a problem with
the Antilock Brake System (ABS). Check the ABS as
soon as possible and have your vehicle serviced by your
dealer/retailer. SeeBrakes on page 5-38andAntilock
Brake System Warning Light on page 3-34for more
information. Press and release the reset stem to
acknowledge the message and clear it from the display.
BRAKES
This message displays if there is a problem with the
brakes. Check the brakes as soon as possible and have
your vehicle serviced by your dealer/retailer. See
Brakes on page 5-38andBrake System Warning Light
on page 3-33for more information. Press and release
the reset stem to acknowledge the message and clear it
from the display.
CHANGE OIL
This message displays when the oil needs to be
changed. Check the oil in your vehicle as soon as
possible and have your vehicle serviced by your
dealer/retailer. SeeEngine Oil on page 5-15and
Scheduled Maintenance on page 6-4for more
information. Press and release the reset stem to
acknowledge the message and clear it from the display.
DOORS
This message displays when one or more of the doors
is ajar. Check all the doors on your vehicle to make
sure they are closed. The message clears from
the display after all of the doors are closed.
ENG (Engine) HOT
This message displays when the engine coolant
temperature is hot. Check the engine coolant
temperature gage. SeeEngine Coolant Temperature
Gage on page 3-35. Have your vehicle serviced by your
dealer/retailer as soon as possible if you suspect the
engine is overheating. SeeEngine Overheating on
page 5-29for more information.
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Adding Coolant
If you need more coolant, add the proper DEX-COOL®
coolant mixture at the coolant recovery tank.
{CAUTION:
Turning the radiator pressure cap when the
engine and radiator are hot can allow steam and
scalding liquids to blow out and burn you badly.
With the coolant recovery tank, you will almost
never have to add coolant at the radiator. Never
turn the radiator pressure cap — even a little —
when the engine and radiator are hot.
Add coolant mixture at the recovery tank, but be careful
not to spill it.
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol,
and it will burn if the engine parts are hot
enough. Do not spill coolant on a hot engine.Occasionally check the coolant level in the radiator.
For information on how to add coolant to the radiator,
seeCooling System on page 5-31.
Radiator Pressure Cap
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
SeeEngine Compartment Overview on page 5-12for
more information on location.
Engine Overheating
A coolant temperature gage is on the instrument panel.
SeeEngine Coolant Temperature Gage on page 3-35.
The air conditioning might stop working if the engine
is too hot. This is normal and helps cool the engine.
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If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can burn
you badly, even if you just open the hood. Stay
away from the engine if you see or hear steam
coming from it. Just turn it off and get
everyone away from the vehicle until it cools
down. Wait until there is no sign of steam or
coolant before you open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch re. You
or others could be badly burned. Stop your
engine if it overheats, and get out of the
vehicle until the engine is cool.
Notice:If your engine catches re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not be
covered by your warranty.
If No Steam Is Coming From Your
Engine
If you get an engine overheat warning but see or hear
no steam, the problem may not be too serious.
Sometimes the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer. See “Driving on Grades” under
Towing a Trailer on page 4-50.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL
while stopped. If it is safe to do so, pull off the
road, shift to PARK (P) or NEUTRAL and let the
engine idle.
2. Turn off the air conditioning.
3. Turn on your heater to full hot at the highest fan
speed and open the windows as necessary.
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(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 can range from 1 to 279.
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.
Aspect Ratio
:The relationship of a tire’s height
to its width.Belt
:A rubber coated layer of cords that is
located between the plies and the tread. Cords
may be made from steel or other reinforcing
materials.
Bead
:The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.
Cold Tire Pressure
:The amount of air pressure in
a tire, measured in pounds per square inch (psi) or
kilopascals (kPa) before a tire has built up heat
from driving. SeeInflation - Tire Pressure on
page 5-62.
Curb Weight
:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant,
but without passengers and cargo.
DOT Markings
:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identication Number (TIN),
an alphanumeric designator which can also identify
the tire manufacturer, production plant, brand,
and date of production.
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