2005 HUMMER H2 light

Airbag Readiness Light
There is an airbag readiness light on the instrument
panel, which shows the airbag symbol. The system
checks the airbag’s electrical system for malfunctions.
The light tells you if there is an electrical problem.
The system check includes the airbag sensors, the
airbag modules, the wiring and the crash sensing and
diagnostic module. For more information on the
airbag system, seeAirbag System on page 1-58.
This light will come on
when you start your
vehicle, and it will ash for
a few seconds. Then the
light should go out. This
means the system is ready.
If the airbag readiness light stays on after you start the
vehicle or comes on when you are driving, your
airbag system may not work properly. Have your vehicle
serviced right away.{CAUTION:
If the airbag readiness light stays on after you
start your vehicle, it means the airbag system
may not be working properly. The airbags in
your vehicle may not inate in a crash, or they
could even inate without a crash. To help
avoid injury to yourself or others, have your
vehicle serviced right away if the airbag
readiness light stays on after you start your
vehicle.
The airbag readiness light should ash for a few
seconds when you turn the ignition key to RUN. If the
light doesn’t come on then, have it xed so it will
be ready to warn you if there is a problem.
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Airbag Off Light
When you turn the right front passenger’s airbag off,
this light will come on and stay on to remind you that the
airbag has been turned off. This light will go off when
you turn the airbag back on again. SeeAirbag Off
Switch on page 1-65for more on this, including
important safety information.{CAUTION:
If the right front passenger’s airbag is turned
off for a person who is not in a risk group
identied by the national government, that
person will not have the extra protection of an
airbag. In a crash, the airbag will not be able to
inate and help protect the person sitting
there. Do not turn off the passenger’s airbag
unless the person sitting there is in a risk
group. See″Airbag Off Switch″in the Index for
more on this, including important safety
information.
United States
Canada
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{CAUTION:
If the airbag readiness light ever comes on
when you have turned off the airbag, it means
that something may be wrong with the airbag
system. The right front passenger’s airbag
could inate even though the switch is off. If
this ever happens, do not let anyone whom the
national government has identied as a
member of a passenger airbag risk group sit in
the right front passenger’s position (for
example, do not secure a rear-facing child
restraint in the right front passenger’s seat)
until you have your vehicle serviced. See
Airbag Off Switch on page 1-65, for more on
this, including important safety information.
Charging System Light
The charging system 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. It could indicate
that you have problems with a generator drive belt, or
another electrical problem. Have it checked right
away. Driving while this light is on could drain your
battery.
When this light comes on the DIC will also display the
battery not charging message. SeeDIC Warnings
and Messages on page 3-47.
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.
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Voltmeter Gage
When your engine is not
running, but the ignition is
in RUN, this gage
shows your battery’s state
of charge in DC volts.
When the engine is running, the gage shows the
condition of the charging system. Readings between the
low and high warning zones indicate the normal
operating range.
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 maximum power.You can only drive for a short time with the reading in
either warning zone. If you must drive, turn off all
unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.
Brake System Warning Light
With the ignition on, the brake system warning light will
ash when you set the parking brake. The light will
ash if the parking brake doesn’t release fully. If you try
to drive with the parking brake engaged, a chime will
sound when the vehicle speed is greater than
3 mph (5 km/h).
Your vehicle’s hydraulic brake system is divided into
two parts. If one part isn’t 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.
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This light should come on briey when you turn the
ignition key to RUN. If it doesn’t come on then, have it
xed so it will be ready to warn you if there’s a
problem.
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 4-64.
{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. United States
Canada
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Anti-Lock Brake System Warning
Light
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay on for
several seconds.
That’s normal. If the light doesn’t come on then, have it
xed so it will be ready to warn you if there is a
problem.
If the light stays on, or comes on when you’re driving,
your vehicle needs service. You will also hear a
chime sound when the light is on steady. If the regular
brake system warning light isn’t on, you still have
brakes, but you don’t have anti-lock brakes. If the
regular brake system warning light is also on you don’t
have anti-lock brakes and there’s a problem with
your regular brakes. In addition to both lights, you will
also hear a chime sound on the rst occurrence of
a problem and each time the vehicle is shut off and then
restarted. SeeBrake System Warning Light on
page 3-32.
Traction Off Light
The traction off light will
come on when a traction
control system or anti-lock
brake system problem
has been detected.
The vehicle may need
service.
When this light is on, the system will not limit wheel
spin. Adjust your driving accordingly. SeeTraction
Control System (TCS) on page 4-9.
If the Traction Control System (TCS) detects that the
vehicle’s brake’s are overheating, the TCS will shut off
and the traction off light will come on. When the
brakes cool off, the TCS will turn back on automatically
and the traction off light will go out.
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Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with 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.
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.
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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 Your 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 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.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-5. 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.
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