engine HUMMER H2 2008 Owner's Guide

Charging System Light
This light will come on
briey when you turn
on the ignition, but
the engine is not running,
as a check to show
you it is working.
It should go out once the engine is running. If it stays
on, or comes on while you are driving, you may have
a problem with the charging system. A charging system
Driver Information Center (DIC) message may also
appear. SeeDIC Warnings and Messages on page 3-56
for more information. This light could indicate that
you have problems with a generator drive belt, or
another electrical problem. Have it checked right away.
If you must drive a short distance with the light on,
be certain to turn off all your accessories, such as
the radio and air conditioner.
Voltmeter Gage
When your engine is
not running, but the
ignition is on, this gage
shows the battery’s
state of charge in
DC volts.
When the engine is running, the gage shows the
condition of the charging system. The charging system
regulates voltage based on the state of the battery
for improved fuel economy and battery life. The gage
may transition from a higher to lower or a lower to
higher reading, this is normal. Readings between
the low and high warning zones indicate the normal
operating range. The gage may also read low during
the fuel economy mode, this is normal.
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Readings in the low warning zone may occur when a
large number of electrical accessories are operating
in the vehicle and the engine is left at an idle for
an extended period. This condition is normal since
the charging system is not able to provide full power
at engine idle. As engine speeds are increased,
this condition should correct itself as higher engine
speeds allow the charging system to create full power.
If there is a problem with the battery charging system,
this light will come on or the SERVICE BATTERY
CHARGING SYSTEM DIC message will display.
SeeDIC Warnings and Messages on page 3-56
andCharging System Light on page 3-37for
more information.
Brake System Warning Light
With the ignition on, the brake system warning
light will come on when you set the parking brake.
If you try to drive with the parking brake engaged,
a chime will sound when the vehicle speed is
greater than 5 mph (8 km/h).Your vehicle’s hydraulic brake system is divided into
two parts. If one part is not working, the other part
can still work and stop you. For good braking, though,
you need both parts working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have your brake system
inspected right away.
This light may also come on due to low brake uid.
SeeBrakes on page 5-36for more information.
This light should come on briey when you turn the
ignition key to RUN. If it does not come on then,
have it xed so it will be ready to warn you if there
is a problem.United StatesCanada
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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.
If the light comes on while you are driving, pull off
the road and stop carefully. You may notice that the
pedal is harder to push or may go closer to the oor.
It may take longer to stop. If the light is still on, have
the vehicle towed for service. SeeTowing Your
Vehicle on page 4-51.
Antilock Brake System
Warning Light
For vehicles with
the Antilock Brake
System (ABS), this
light will come on
briey when you
start the engine.
That is normal. If the light does not come on then,
have it xed so it will be ready to warn you if there
is a problem.
If the ABS light stays on, turn the ignition off, if the light
comes on when you are driving, stop as soon as it is
safely possible and turn the ignition off. Then start the
engine again to reset the system. If the ABS light still
stays on, or comes on again while 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 antilock brakes. If the regular brake system
warning light is also on, you do not have antilock
brakes and there is a problem with your regular brakes.
SeeBrake System Warning Light on page 3-38
For vehicles with a Driver Information Center (DIC),
seeDIC Warnings and Messages on page 3-56for
all brake related DIC messages.
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StabiliTrak®Indicator Light
If equipped, this
warning light should
come on briey when
the engine is started.
If the warning light does not come on then, have it xed
so it will be ready to warn you if there is a problem.
If it stays on, or comes on when you are driving,
there may be a problem with your StabiliTrak
®system
and your vehicle may need service. When this warning
light is on, the system is off and will not limit wheel
spin. Adjust your driving accordingly.
This light will also ash when the StabiliTrak
®system
is active.
If the StabiliTrak
®system warning light comes on
and stays on for an extended period of time when
the system is turned on, your vehicle needs service.
SeeStabiliTrak
®System on page 4-7for more
information.
Engine Coolant Temperature Gage
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 uctuate 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.
SeeEngine Overheating on page 5-27.
United StatesCanada
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Tire Pressure Light
This light comes on
briey when the
engine is started.
This light will also come on when one or more of
your tires are signicantly underinated.A tire pressure message in the Driver Information
Center (DIC), may accompany the light. SeeDIC
Warnings and Messages on page 3-56for 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 5-55for more information.
If a problem is detected with the Tire Pressure
Monitor System, this light will ash for approximately
60 seconds and then stay on solid for the remainder of
the ignition cycle. SeeTire Pressure Monitor System
on page 5-62for more information.
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Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation
of the fuel, ignition, and emission control systems.
It makes sure 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 an OBD II
problem and service
is required.
Malfunctions often are indicated by the system before
any problem is apparent. This can 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 a while, the emission controls
might not work as well, your vehicle’s fuel economy
might not be as good, and the engine might not
run as smoothly. This could lead to costly repairs
that might 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 can cause this light to
come on. Modications to these systems could
lead to costly repairs not covered by your warranty.
This could also result in a failure to pass a
required Emission Inspection/Maintenance test.
SeeAccessories and Modifications on page 5-3.
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This light comes on, as a check to show it is working,
when the ignition is turned ON/RUN but the engine is not
running. If the light does not come on, have it repaired.
This light also comes on during a malfunction in
one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and could damage the emission control system
on your vehicle. Diagnosis and service might
be required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service might be required.
If the Light is Flashing
The following can prevent more serious damage
to your vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid 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 the vehicle.
Turn the ignition 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/retailer
for service as soon as possible.
If the Light Is On Steady
You might 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 5-7. The diagnostic
system can determine if the fuel cap has been left off or
improperly installed. A loose or missing fuel cap allows
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 vehicle’s electrical system might be wet. The
condition is usually 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 5-5. Poor fuel quality
causes the engine not to run as efficiently as designed.
You might 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 might 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/retailer can check the vehicle. Your
dealer/retailer has the proper test equipment and
diagnostic tools to x any mechanical or electrical
problems that might have developed.Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have
or might 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 the battery or
if the battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This can 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/retailer can prepare
the vehicle for inspection.
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Oil Pressure Gage
The oil pressure gage shows the engine oil pressure
in psi (pounds per square inch) when the engine
is running. Canadian vehicles indicate pressure
in kPa (kilopascals).
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.When the oil pressure reaches the low pressure zone,
the OIL PRESSURE LOW STOP ENGINE message
will appear in the Driver Information Center (DIC).
SeeDIC Warnings and Messages on page 3-56and
Engine Oil on page 5-13for more information.
A reading in the low pressure zone may be caused by a
dangerously low oil level or some other problem causing
low oil pressure. Check your oil as soon as possible.
{CAUTION:
Do not keep driving if the oil pressure is low.
If you do, your engine can become so hot that
it catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be covered
by your warranty. Always follow the maintenance
schedule in this manual for changing engine oil. United StatesCanada
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Oil Pressure Light
{CAUTION:
Do not keep driving if the oil pressure is low.
If you do, your engine can become so hot that
it catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be covered
by your warranty. Always follow the maintenance
schedule in this manual for changing engine oil.
This light will come on
briey when you start your
engine. If it does not,
have your vehicle serviced.
When the light comes on and stays on, it means that
oil is not owing through your engine properly. You could
be low on oil and you might have some other system
problem.
Security Light
For information regarding
this light and the vehicle’s
security system, see
Content Theft-Deterrent
on page 2-24.
Cruise Control Light
This light comes on
whenever you set
the cruise control.
The light goes out when the cruise control is turned off.
SeeCruise Control on page 3-12for more information.
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