2008 HUMMER H2 check engine light

If the engine still does not start, and the key appears to
be undamaged, try another ignition key. At this time,
you may also want to check the fuse, seeFuses
and Circuit Breakers on page 5-110. If the engine still
does not start with the other key, your vehicle needs
service. If your vehicle does start, the rst key may be
faulty. See your dealer/retailer who can service the
PASS-Key
®III+ to have a new key made. In an
emergency, contact Roadside Assistance.
It is possible for the PASS-Key
®III+ decoder to learn
the transponder value of a new or replacement key.
Up to 10 keys may be programmed for the vehicle.
The following procedure is for programming additional
keys only. If all the currently programmed keys are
lost or do not operate, you must see your dealer/retailer
or a locksmith who can service PASS-Key
®III+ to
have keys made and programmed to the system.
See your dealer/retailer or a locksmith who can service
PASS-Key
®III+ to get a new key blank that is cut
exactly as the ignition key that operates the system.To program the new additional key:
1. Verify that the new key has a
1stamped on it.
2. Insert the original, already programmed, key in the
ignition and start the engine. If the engine will not
start, see your dealer/retailer for service.
3. After the engine has started, turn the key to
LOCK/OFF, and remove the key.
4. Insert the new key to be programmed and turn it to
the ON/RUN position within ve seconds of turning
the ignition to the LOCK/OFF position in Step 3.
The security light will turn off once the key has been
programmed.
5. Repeat Steps 1 through 4 if additional keys are to
be programmed.
If you lose or damage your PASS-Key
®III+ key, see
your dealer/retailer or a locksmith who can service
PASS-Key
®III+ to have a new key made.
Do not leave the key or device that disarms or
deactivates the theft deterrent system in the vehicle.
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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 also has a Driver Information Center (DIC)
that works along with warning lights and gages.
SeeDIC Warnings and Messages on page 3-56
for more information.
3-31

Speedometer and Odometer
Your speedometer lets you see your speed in both
miles per hour (mph) and kilometers per hour (km/h).
Your vehicle’s odometer works together with the
driver information center. You can set a Trip odometer.
See “Trip Odometer” underDIC Operation and
Displays (Using DIC Buttons) on page 3-49or
DIC Operation and Displays (Using Trip Odometer
Reset Stem) on page 3-54for more information.
The odometer mileage can be checked without the
vehicle running. Simply press the trip stem on the
instrument panel cluster.
If your vehicle ever needs a new odometer installed,
the new one will be set to the correct mileage total
of the old odometer.
Trip Odometer
The trip odometer can tell you how far your vehicle has
been driven since you last set the trip odometer to zero.
Press the trip stem to toggle between the trip odometer
and the regular odometer. Holding the trip stem for
approximately one second while the trip odometer is
displayed will reset it.
To display the odometer reading with the ignition off,
press the trip stem.
Tachometer
Your tachometer displays the engine speed in
revolutions per minute (rpm).
Safety Belt Reminders
Safety Belt Reminder Light
When the engine is started, a chime will come on for
several seconds to remind people to fasten their safety
belts, unless the driver’s safety belt is already buckled.
The safety belt light will
also come on and stay
on for several seconds,
then it will ash for
several more.
This chime and light is repeated if the driver remains
unbuckled and the vehicle is in motion. If the driver’s
belt is already buckled, neither the chime nor the
light will come on.
3-33

Airbag Readiness Light
There is an airbag readiness light on the center
overhead console, 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 1-64.
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 the engine is started. If the light does not come
on then, have it xed so it will be ready to warn you if
there is a problem.
3-34

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.
3-37

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.
3-41

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.
3-42

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.
3-43