check engine light HUMMER H2 2006 Owners Manual

While the alarm is set, the power door unlock switch is
not operational.
If the alarm does not sound when it should but the
headlamps ash, check to see if the horn works. The
horn fuse may be blown. To replace the fuse, see
Instrument Panel Fuse Block on page 5-116and
Underhood Fuse Block on page 5-119.
If the alarm does not sound or the headlamps do not
ash, the vehicle should be serviced by your dealer.
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. See
Instrument Panel Fuse Block on page 5-116and
Underhood Fuse Block on page 5-119. See your dealer
for service.
In an emergency, call the Roadside Assistance Center.
SeeRoadside Assistance Program on page 7-6.
2-23

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 5-109for 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.
Instrument Panel Brightness
The thumbwheel for this feature is located next to the
exterior lamps control.
D(Instrument Panel Lights):Turn the thumbwheel
up or down to brighten or dim the instrument panel
lights and the radio display. This will only work if
the headlamps or parking lamps are on.
To turn on the dome lamps, with the vehicle doors
closed, turn the thumbwheel all the way up.
3-17

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 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 also has a Driver Information Center (DIC)
that works along with warning lights and gages. See
DIC Warnings and Messages on page 3-48.
3-29

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” underDIC
Operation and Displays on page 3-45.
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.
3-31

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 3-48.
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
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.
3-34

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. SeeAccessories
and Modifications on page 5-3.
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.
3-39

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 5-8. The
diagnostic system can determine if the fuel cap hasbeen 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.
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.
3-40

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 GM 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 States
Canada
3-41

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 5-14.
{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 2-23.
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 2-21for
additional information regarding the security light.
3-42

Select Button
r
(Select):Press the select button to reset certain
DIC functions and set your customization settings.
For example, this button will reset the trip odometers
and enables you to scroll through and select the
language in which the DIC information will appear.
DIC Warnings and Messages
Warning messages are displayed on the Driver
Information Center (DIC) to notify the driver that the
status of the vehicle has changed and that some action
may be needed by the driver to correct the condition.
If there is more than one message that needs to
be displayed they will appear one after another. Some
messages may not require immediate action, but
you should press any of the four DIC buttons located on
the steering wheel or the trip odometer reset stem
located on the instrument panel cluster to acknowledge
that you received the messages and to clear them
from the display. Some messages cannot be cleared
from the display because they are more urgent.These messages require action before they can be
removed from the DIC display. You should take
any messages that appear on the display seriously and
remember that clearing the messages will only make
the messages disappear, not correct the problem.
The following are the possible messages that can be
displayed and some information about them.
BATTERY NOT CHARGING
If the battery is not charging during operation, this
message will appear on the DIC. Driving with this
problem could drain your battery. Have the electrical
system checked as soon as possible by your dealer.
SeeCharging System Light on page 3-34andVoltmeter
Gage on page 3-34for more information. Pressing
any of the four DIC buttons or the trip odometer reset
stem will clear the message from the DIC display.
CHANGE ENGINE OIL
This message is displayed when the engine oil needs to
be changed. See “Engine Oil Life System” underDIC
Operation and Displays on page 3-45andEngine
Oil Life System on page 5-17for information on how to
reset the message. Also, seeEngine Oil on page 5-14
for more information. This message will clear itself after
10 seconds until the next ignition cycle.
3-48