check engine light HUMMER H2 2007 Owners Manual

Passlock®
Your vehicle is equipped with the Passlock®
theft-deterrent system.
Passlock
®is a passive theft-deterrent system.
Passlock®enables fuel if the ignition lock cylinder
is turned with a valid key. If a correct key is not
used or the ignition lock cylinder is tampered with,
the fuel system is disabled and the vehicle will
not start.
During normal operation, the security light will turn
off approximately ve seconds after the key is
turned to RUN.
If the engine stalls and the security light ashes,
wait about 10 minutes until the light stops
ashing before trying to restart the engine.
Remember to release the key from START as
soon as the engine starts.If the engine does not start after three tries, the
vehicle needs service.
If the engine is running and the security light comes
on, you will be able to restart the engine if you turn
the engine off. However, your Passlock
®system is
not working properly and must be serviced by your
dealer. Your vehicle is not protected by Passlock
®
at this time. You may also want to check the fuse.
SeeInstrument Panel Fuse Block on page 504and
Underhood Fuse Block on page 507. See your
dealer for service.
In an emergency, call the Roadside Assistance
Center. SeeRoadside Assistance Program
on page 542.
118

Off-Road Lamps
Notice:If you drive your vehicle through an
automatic car wash that does not have enough
clearance for any roof-mounted accessories
(such as off-road lamps or a roof basket)
on your vehicle, you can damage your vehicle.
To avoid damaging your vehicle in a car
wash, remove any roof-mounted accessories if
you can, and do not use an automatic car
wash while roof-mounted accessories are on
your vehicle. SeeWashing Your Vehicle
on page 495for more information.
The off-road lamps, if equipped, provide auxiliary
lighting when your vehicle is used off road.
These lamps are not intended to be used in
conjunction with, or 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 button for the off-road lamps is located in the
overhead console.
To use the lamps, be sure the engine is running.
Remove the covers from the lamps and press
the button to turn them on. Press the button again
to turn them off. An indicator light will glow near
the button 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
return the lamps to the upright position
and remove the covers before turning on the
off-road lamps.
The off-road lamps will remain on even after the
ignition is turned off. The off-road lamps button
must be pressed to turn them off.
Loading objects onto the off-road light bar may
cause damage to the light bar or off road lamps.
Repairs would not be covered by your warranty.
Do not load objects on the off-road light bar.
190

Operation Tips

Keep the hood and front air inlets free of ice,
snow, or any other obstruction (such as
leaves). The heater and defroster will work far
better, reducing the chance of fogging the
inside of your windows.
Keep the air path under the front seats clear
of objects. This helps air to circulate
throughout your vehicle.
Adding outside equipment to the front of your
vehicle, such as hood-air deectors, etc.,
may affect the performance of the heating and
air conditioning system. Check with your
dealer before adding equipment to the outside
of your vehicle.
Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages
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 orreplacement. 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 also has a Driver Information
Center (DIC) that works along with warning lights
and gages. SeeDIC Warnings and Messages
on page 226.
204

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 A and
Trip B odometer. See “Trip Information” under
DIC Operation and Displays on page 222.
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 reset button, located on the instrument
panel cluster next to the trip odometer display,
to toggle between the trip odometer and the
regular odometer. Holding the reset button for
approximately one second while the trip odometer
is displayed will reset it.To display the odometer reading with the ignition
off, press the reset button.
Tachometer
Your tachometer displays the engine speed in
revolutions per minute (rpm).
Safety Belt Reminder Light
When the key is turned to RUN or START, a chime
will be provided for several seconds to remind
people to buckle their safety belts. The driver safety
belt light will also be provided and stay on for
several seconds, then it will ash for several more.
You should buckle your seat belt.
This chime and light will
be repeated if the driver
remains unbuckled
and the vehicle
is in motion.
If the driver’s belt is buckled, neither the chime nor
the light will be provided.
206

{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. SeeAirbag Off Switch on
page 84, for more on this, including
important safety information.
Charging System Light
The charging system
light will come on briey
when the ignition is on,
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 the battery.
When this light comes on the DIC will also display
the SERVICE BATTERY CHARGING SYSTEM
message. SeeDIC Warnings and Messages
on page 226for more information.
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.
209

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 392.
215

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.
216

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 397.
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.
SeeGasoline Octane on page 394. 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.
217

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.
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.
United StatesCanada
218

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. SeeEngine Oil on
page 404.
{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.
Security Light
This light will come on
briey when you turn
the key toward START.
The light will stay on
until the engine starts.
If the light ashes, the Passlock
®system has
entered a tamper mode. If the vehicle fails to start,
seePasslock
®on page 118.
If the light comes on continuously while driving
and stays on, there may be a problem with
the Passlock
®system. Your vehicle will not be
protected by Passlock®, and you should see your
dealer.
Also, seeContent Theft-Deterrent on page 116for
additional information regarding the security light.
219