HUMMER H3 2008 Owners Manual

Daytime Running Lamps (DRL)
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the
day. DRL can be helpful in many different driving
conditions, but they can be especially helpful in the short
periods after dawn and before sunset. Fully functional
daytime running lamps are required on all vehicles
rst sold in Canada.
The DRL system will come on when the following
conditions are met:
The ignition is on.
The exterior lamps control is in AUTO.
The transmission is not in PARK (P) if you have an
automatic transmission.
The light sensor determines it is daytime.
When the DRL are on, no other lamps are on. The
instrument panel will not be lit up either. For vehicles rst
sold in Canada, if parking lamps are manually turned
on, DRL will stay on.
When it begins to get dark, the automatic headlamp
system will switch from DRL to the headlamps.
As with any vehicle, you should turn on the regular
headlamp system when you need it.
To turn off the DRL, seeExterior Lamps on page 3-15.Vehicles rst sold in Canada cannot turn off DRL unless
certain conditions are met. SeeExterior Lamps on
page 3-15.
Automatic Headlamp System
When it is dark enough outside, the automatic headlamp
system will turn on after the transmission has been
shifted from PARK (P) to DRIVE (D). The headlamps,
taillamps, sidemarker, parking lamps, roof marker lamps,
and the instrument panel lights will turn on at normal
brightness. The radio lights will become more dim when
the headlights are off compared to when the headlights
are on.
Your vehicle has a light sensor located on the top of the
instrument panel. Be sure it is not covered, or the
system will be on whenever the ignition is on.
The system may also turn on the headlamps when
driving through a parking garage, heavy overcast
weather, or a tunnel. This is normal.
There is a delay in the transition between the daytime
and nighttime operation of the Daytime Running
Lamps (DRL) and the automatic headlamp system so
that driving under bridges or bright overhead street lights
does not affect the system. The DRL and automatic
headlamp system will only be affected when the
light sensor detects a change in lighting lasting longer
than the delay.
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If you start your vehicle in a dark garage, the automatic
headlamp system will come on immediately. Once
you leave the garage, it will take about one minute for
the automatic headlamp system to change to DRL if it is
light outside. During that delay, the instrument panel
cluster may not be as bright as usual. Make sure
the instrument panel brightness control is in the full
bright position. SeeInstrument Panel Brightness
on page 3-19.
Off-Road Lamps
The off-road lamps, if the vehicle has them, provide
auxiliary lighting when the vehicle is used off road.
These lamps are not intended to be used in place of
existing vehicle lighting. The lamps are not to be used
on any public street or highway and are to be covered
when not in use. Check your state and local laws before
installing or using any auxiliary lighting. In some
states it may be necessary to remove the roof lamps
when operating the vehicle on the highway.The switches for the off-road lamps are located in the
center of the instrument panel below the climate
controls. One switch is used for the front lower-grille
mounted off-road lamps, if the vehicle has them, and the
other switch is used for the roof-mounted off-road
lamps, if the vehicle has them.
To use the lamps, remove the covers from the lamps and
press the switch to turn them on or off. An indicator light
on the switch will turn on when the lamps are on.
Notice:Turning on the off-road lamps before
removing the lamp covers could damage the
off-road lamps and the covers. Always remove the
covers before turning on the off-road lamps.
The off-road lamps remain on even after the ignition is
turned off. The off-road lamp switch must be pressed
to turn them off.Roof Mounted Off-Road
Light Switch
Lower Grille Off-Road
Light Switch
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Fog Lamps
Your vehicle has fog lamps. You can use them for
better vision in foggy or misty conditions. Your parking
lamps and/or low-beam headlamps must be on for
your fog lamps to work.
The fog lamp button is
located in the exterior
lamps control.
Press the button to turn the fog lamps on while the
headlamps or parking lamps are on. Press the button
again to turn them off. An indicator light will glow in the
button when the fog lamps are on.
Remember, fog lamps alone will not give off as much
light as your headlamps. Never use your fog lamps
in the dark without turning on the headlamps.
The fog lamps will go off whenever your high-beam
headlamps come on. When the high beams go off, the
fog lamps will come on again.
Some localities have laws that require the headlamps to
be on along with the fog lamps.
Instrument Panel Brightness
D(Instrument Panel Brightness):This feature
controls the brightness of the instrument panel lights.
The thumbwheel for this feature is located next to
the exterior lamp control.
Turn the thumbwheel up or down to brighten or dim the
instrument panel lights and the radio display. The
instrument panel lights, cluster, and radio display do not
dim to complete darkness. Turn the thumbwheel all
the way up to turn the dome lamps on.
Dome Lamp
The dome and footwell lamps come on when any door
is opened. The dome lamps are located in the cargo
and front area of the vehicle.
The dome and footwell lamps can be turned on by
turning the thumbwheel, located next to the exterior
lamps control, all the way up. In this position, the lamps
remain on whether a door is opened or closed.
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Dome Lamp Override
E(Dome Lamp Override):You can use the dome
override button, located below the exterior lamps control,
to set the dome and footwell lamps to come on
automatically when a door is opened, or to remain off.
To turn the lamps off, press the button into the in
position. With the button in this position, the dome lamps
will remain off when the doors are open. To return the
lamps to automatic operation, press the button again
and return it to the out position. With the button in this
position, the dome lamps will come on when you
open a door.
Exit Lighting
With exit lighting, the interior lamps will come on when
you remove the key from the ignition. The lamps will not
come on if the dome override button is pressed in.
Reading Lamps
Your vehicle has reading lamps. Press the button
located next to the lamp to turn them on or off.
These lamps will not come on with the dome lamps.
Electric Power Management
The vehicle has Electric Power Management (EPM) that
estimates the battery’s temperature and state of
charge. It then adjusts the voltage for best performance
and extended life of the battery.
When the battery’s state of charge is low, the voltage is
raised slightly to quickly put the charge back in. When
the state of charge is high, the voltage is lowered slightly
to prevent overcharging. If the vehicle has a voltmeter
gage, you may see the voltage move up or down. This is
normal. If there is a problem, an alert will be displayed.
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 loads are on: 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.
Battery Run-Down Protection
This feature shuts off the dome lamp if it is left on for
more than 20 minutes when the ignition is in LOCK. This
will help prevent your battery from running down.
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Accessory Power Outlet(s)
Your vehicle has accessory power outlets.
With accessory power outlets you can plug in auxiliary
electrical equipment such as a cellular telephone or
CB radio.
Your vehicle has two accessory power outlets located on
the lower part of the instrument panel below the climate
control system and there may be one located in the rear
cargo area. A small cap must be pulled down to access
an accessory power outlet. When not using an outlet, be
sure to cover it with the protective cap.
Notice:Leaving electrical equipment on for
extended periods will drain the battery. Always
unplug electrical equipment when not in use and do
not plug in equipment that exceeds the maximum
amperage rating of 20 amperes.Certain electrical accessories may not be compatible
with the accessory power outlet and could result
in blown vehicle or adapter fuses. If you experience a
problem, see your dealer for additional information
on accessory power outlets.
Notice:Adding any electrical equipment to your
vehicle may damage it or keep other components
from working as they should. The repairs would not
be covered by your warranty. Do not use equipment
exceeding maximum amperage rating of 20 amperes.
Check with your dealer/retailer before adding
electrical equipment.
When adding electrical equipment, be sure to follow the
proper installation instructions included with the
equipment.
Notice:Improper use of the power outlet can cause
damage not covered by your warranty. Do not
hang any type of accessory or accessory bracket
from the plug because the power outlets are
designed for accessory power plugs only.
3-21

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.
3-25

Instrument Panel Cluster
Your instrument panel cluster is designed to let you know at a glance how your vehicle is running. You will know how
fast you are going, about how much fuel you have used, and many other things you will need to know to drive
safely and economically.
United States 3.7L L5 Automatic Transmission version shown, 5.3L V8, Canada and Manual
Transmission similar
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