2007 HUMMER H3 engine

#(Air Conditioning):Press 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.
The air conditioning will not function if the fan
is turned off. If air conditioning is selected with
fan off, the indicator will ash three times and
then turn 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.
The right knob on the control panel is used to
direct the airow inside the vehicle. Turn the knob
to select one of the following modes:
@(Recirculation):Press the center knob on
the control panel to recirculate air inside the
vehicle and prevent outside air from coming in.
It can be used to prevent outside odors from
entering your vehicle and cool the air inside your
vehicle more quickly. Press this button to turn
the recirculation mode on or off. An indicator light
on the button will come on to let you know the
recirculation mode is activated.
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Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages
that may be on your vehicle. The pictures will
help you 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 your 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 you will see in the details 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 when 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 warning lights
and gages. They are a big help.
Your vehicle has a DIC that works along with the
warning lights and gages. SeeDriver Information
Center (DIC) on page 192for more information.
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Speedometer and Odometer
Your speedometer lets you see your speed
in both miles per hour (mph) and kilometers
per hour (km/h).
Your odometer shows how far your vehicle has
been driven, in either miles or kilometers.
The odometer mileage can be checked with the
ignition off. Simply press the trip information
stem. See “Odometer” underDIC Controls and
Displays on page 192for more information.
You may wonder what happens if your vehicle
needs a new odometer installed. If the new
one can be set to the mileage total of the old
odometer, then it must be. But if it cannot, then
it is set at zero, and a label must be put on
the driver’s door to show the old mileage reading
when the new odometer was installed.
Trip Odometer
Your vehicle has a trip odometer that can tell you
how far your vehicle has been driven since you last
set the trip odometer to zero.
See “Trip Odometer” underDIC Controls and
Displays on page 192for more information.
Tachometer
The tachometer
displays the engine
speed in revolutions
per minute (rpm).
Notice:If you operate the engine with the
tachometer in the shaded warning area, your
vehicle could be damaged, and the damages
would not be covered by your warranty.
Do not operate the engine with the tachometer
in the shaded warning area.
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{CAUTION:
Your brake system may not be working
properly if the brake system warning
light is on. Driving with the brake system
warning light on can lead to an accident.
If the light is still on after you have pulled
off the road and stopped carefully, have
the vehicle towed for service.
Anti-Lock Brake System
Warning Light
With the Anti-Lock Brake
System (ABS), this light
will come on briey when
you start your engine
to show it is working.
Then it will turn off.
This is normal.
If the light stays on, or comes on when you are
driving, your vehicle needs service. If the regular
brake system warning light is not on, you still
have brakes, but you do not have anti-lock brakes.
If the regular brake system warning light is also
on, you do not have anti-lock brakes and there
is a problem with your regular brakes. SeeBrake
System Warning Light on page 182.
The ABS warning light should come on briey
when you turn the ignition key to ON. If the light
does not come on then, have it xed so it will
be ready to warn you if there is a problem.
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Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
If the gage pointer is in the shaded area of the
gage, the engine is too hot. It means that your
engine coolant has overheated. If you have been
operating your vehicle under normal driving
conditions, you should pull off the road, stop your
vehicle and turn off the engine as soon as possible.
SeeEngine Overheating on page 338for more
information.
Tire Pressure Light
This light should
come on briey
when you turn the
ignition to ON.
This light will also come on when one or more
of your tires are signicantly underinated.
A LOW TIRE message will also appear in the
Driver Information Center (DIC), seeDIC Warnings
and Messages on page 196for more information.
Stop and check your tires as soon as it is safe to do
so. If underinated, inate to the proper pressure.
SeeTires on page 367for more information.
This light will ash for 60 seconds and then turn
on solid if a problem is detected with the Tire
Pressure Monitor system. SeeTire Pressure
Monitor System on page 376for more information.
United StatesCanada
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Malfunction Indicator Lamp
Check Engine Light
Your vehicle has a
computer which
monitors operation
of the fuel, ignition,
and emission control
systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended
to assure that emissions are at acceptable
levels for the life of the vehicle, helping to produce
a cleaner environment. The check engine light
comes on to indicate that there is a problem and
service is required. Malfunctions often will be
indicated by the system before any problem is
apparent. This may prevent more serious damage
to your vehicle. This system is also designed to
assist your service technician in correctly
diagnosing any malfunction.Notice:If you keep driving your vehicle with
this light on, after awhile, your emission
controls may not work as well, your fuel
economy may not be as good, and your engine
may not run as smoothly. This could lead to
costly repairs that may not be covered by
your warranty.
Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system
of your vehicle or the replacement of the
original tires with other than those of the same
Tire Performance Criteria (TPC) can affect
your vehicle’s emission controls and may
cause this light to come on. Modications to
these systems could lead to costly repairs
not covered by your warranty. This may also
result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 314.
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This light should come on, as a check to show
you it is working, when the ignition is on and
the engine is not running. If the light does
not come on, have it repaired. This light will also
come on during a malfunction in one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and may damage the emission control system
on your vehicle. Diagnosis and service may
be required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
If the Light is Flashing
The following may prevent more serious damage
to your vehicle:
Reducing vehicle speed
Avoiding hard accelerations
Avoiding steep uphill grades
If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible
If the light stops ashing and remains on steady,
see “If the Light Is On Steady” following.If the light continues to ash, when it is safe to
do so, stop the vehicle. Find a safe place to park
your vehicle. Turn the key off, wait at least
10 seconds and restart the engine. If the light
remains on steady, see “If the Light Is On Steady”
following. If the light is still ashing, follow the
previous steps, and see your dealer for service
as soon as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully
install the cap. SeeFilling the Tank on page 318.
The diagnostic system can determine if the fuel cap
has been left off or improperly installed. A loose
or missing fuel cap will allow fuel to evaporate into
the atmosphere. A few driving trips with the cap
properly installed should turn the light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The
condition will usually be corrected when the
electrical system dries out. A few driving trips
should turn the light off.
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Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel.
SeeGasoline Octane on page 316. Poor fuel
quality will cause your engine not to run as
efficiently as designed. You may notice this as
stalling after start-up, stalling when you put
the vehicle into gear, misring, hesitation on
acceleration, or stumbling on acceleration.
(These conditions may go away once the engine
is warmed up.) This will be detected by the
system and cause the light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at
least one full tank of the proper fuel to turn the
light off.
If none of the above steps have made the light
turn off, your dealer can check the vehicle.
Your dealer has the proper test equipment
and diagnostic tools to x any mechanical or
electrical problems that may have developed.Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have
or may begin programs to inspect the emission
control equipment on your vehicle. Failure to pass
this inspection could prevent you from getting a
vehicle registration.
Here are some things you need to know to help
your vehicle pass an inspection:
Your vehicle will not pass this inspection if the
check engine light is on or not working properly.
Your vehicle will not pass this inspection if
the OBD (on-board diagnostic) system determines
that critical emission control systems have not
been completely diagnosed by the system.
The vehicle would be considered not ready for
inspection. This can happen if you have recently
replaced your battery or if your battery has
run down. The diagnostic system is designed
to evaluate critical emission control systems during
normal driving. This may take several days of
routine driving. If you have done this and
your vehicle still does not pass the inspection
for lack of OBD system readiness, your dealer
can prepare the vehicle for inspection.
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