light HUMMER H2 2008 Repair Manual

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

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.
3-44

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.
3-46

Highbeam On Light
This light comes on
when the high-beam
headlamps are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-8
for more information.
Tow/Haul Mode Light
This light comes on
when the Tow/Haul
mode has been activated.
For more information, seeTow/Haul Mode on page 2-36.
Fuel Gage
The fuel gage, when the ignition is on, tells you about
how much fuel you have left in your tank.
The gage will rst indicate empty before you are out of
fuel, and you should get more fuel as soon as possible.
United StatesCanada
3-47

When the fuel tank is low, the FUEL LEVEL LOW
message will appear in the Driver Information
Center (DIC). SeeDIC Warnings and Messages
on page 3-56for more information.
Here are some situations you may experience with
your fuel gage. None of these indicate a problem
with the fuel gage.
At the gas station, the fuel pump shuts off
before the gage reads full.
It takes a little more or less fuel to ll up
than the fuel gage indicated. For example,
the gage may have indicated the tank was
half full, but it actually took a little more
or less than half the tank’s capacity to ll
the tank.
The gage goes back to empty when you
turn off the ignition.
Low Fuel Warning Light
This light, under the
fuel gage, will come
on briey when you
are starting the engine.
This light and a chime will come on when the fuel
tank is low on fuel. There will also be a “FUEL LEVEL
LOW” message on the Driver Information Center,
seeDIC Warnings and Messages on page 3-56for
more information. When you add fuel this light
and message should go off. If it does not, have
your vehicle serviced.
3-48

DIC Warnings and Messages
Messages are displayed on the 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. Multiple messages may appear
one after another.
Some messages may not require immediate action,
but you can press any of the DIC buttons on the
instrument panel or the trip odometer reset stem 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 DIC
display because they are more urgent. These messages
require action before they can be cleared. 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.
CHANGE ENGINE OIL SOON
This message displays when the engine oil needs to
be changed. When you change the engine oil, be sure
to reset the CHANGE ENGINE OIL SOON message.
SeeEngine Oil Life System on page 5-16for information
on how to reset the message. SeeEngine Oil on
page 5-13andScheduled Maintenance on page 6-4
for more information.
CHECK TIRE PRESSURE
This message displays when the pressure in one
or more of the vehicle’s tires needs to be checked. This
message also displays LEFT FRONT, RIGHT FRONT,
LEFT REAR, or RIGHT REAR to indicate which tire
needs to be checked. You can receive more than one
tire pressure message at a time. To read the other
messages that may have been sent at the same time,
press the set/reset button or the trip odometer reset
stem. If a tire pressure message appears on the DIC,
stop as soon as you can. Have the tire pressures
checked and set to those shown on the Tire Loading
Information label. SeeTires on page 5-55,Loading Your
Vehicle on page 4-44, andInflation - Tire Pressure on
page 5-61. The DIC also shows the tire pressure values.
See “DIC Operation and Displays (Using DIC Buttons)”
earlier in this section. If the tire pressure is low,
the low tire pressure warning light comes on.
SeeTire Pressure Light on page 3-41.
3-56

SERVICE AIR BAG
This message displays if there is a problem with
the airbag system. Have your dealer/retailer inspect
the system for problems. SeeAirbag Readiness Light
on page 3-34andAirbag System on page 1-64for
more information.
SERVICE BATTERY CHARGING
SYSTEM
On some vehicles, this message displays if there is a
problem with the battery charging system. Under certain
conditions, the charging system light may also turn
on in the instrument panel cluster. SeeCharging System
Light on page 3-37. Driving with this problem could
drain the battery. Turn off all unnecessary accessories.
Have the electrical system checked as soon as
possible. See your dealer/retailer.
SERVICE BRAKE SYSTEM
This message displays along with the brake system
warning light if there is a problem with the brake system.
SeeBrake System Warning Light on page 3-38. If this
message appears, stop as soon as possible and
turn off the vehicle. Restart the vehicle and check for
the message on the DIC display. If the message is still
displayed or appears again when you begin driving,
the brake system needs service as soon as possible.
See your dealer/retailer.
SERVICE BRAKES SOON
This message displays if there is a problem with the
brake system. If this message appears, stop as soon
as possible and turn off the vehicle. Restart the vehicle
and check for the message on the DIC display. If the
message is still displayed or appears again when
you begin driving, the brake system needs service.
See your dealer/retailer.
SERVICE STABILITRAK
This message displays when there may be a problem
with the StabiliTrak®system. If you see this message,
try to reset the system. Stop; turn off the engine for
at least 15 seconds; then start the engine again. If this
message still comes on, it means there is a problem.
You should see your dealer/retailer for service.
The vehicle is safe to drive, however, you do not
have the benet of StabiliTrak
®, so reduce your
speed and drive accordingly.
SERVICE SUSPENSION SYSTEM
This message displays if a problem occurs with the
suspension system. If this message appears, stop as
soon as possible and turn off the vehicle. Restart
the vehicle and check for the message on the DIC
display. If the message is still displayed, or appears
again when you begin driving, there is a problem with
the air suspension system. See your dealer/retailer
for service.
3-60

SERVICE THEFT DETERRENT SYSTEM
This message displays when there is a problem with
the theft-deterrent system. The vehicle may or may
not restart so you may want to take the vehicle to
your dealer/retailer before turning off the engine.
SeePASS-Key
®III+ Operation on page 2-26for
more information.
SERVICE TIRE MONITOR SYSTEM
This message displays if a part on the Tire Pressure
Monitor System (TPMS) is not working properly.
The tire pressure light also ashes and then remains
on during the same ignition cycle. SeeTire Pressure
Light on page 3-41. Several conditions may cause
this message to appear. SeeTire Pressure Monitor
Operation on page 5-64for more information.
If the warning comes on and stays on, there may
be a problem with the TPMS. See your dealer/retailer.
SERVICE TRACTION CONTROL
This message displays when there is a problem with
the Traction Control System (TCS). When this message
displays, the system will not limit wheel spin. Adjust
your driving accordingly. See your dealer/retailer
for service. SeeTraction Control System (TCS)
on page 4-5andStabiliTrak
®System on page 4-7
for more information.
STABILITRAK OFF
This message displays when you turn off StabiliTrak®,
or when the stability control has been automatically
disabled. To limit wheel spin and realize the full benets
of the stability enhancement system, you should
normally leave StabiliTrak
®on. However, you should
turn StabiliTrak®off if your vehicle gets stuck in
sand, mud, ice, or snow and you want to rock your
vehicle to attempt to free it, or if you are driving
in extreme off-road conditions and require more wheel
spin. SeeIf Your Vehicle is Stuck in Sand, Mud,
Ice, or Snow on page 4-39. To turn the StabiliTrak
®
system on or off, seeStabiliTrak®System on page 4-7.
There are several conditions that can cause this
message to appear.
The message displays if an engine or vehicle
related problem has been detected and the
vehicle needs service. See your dealer/retailer.
The message also displays if the vehicle is
shifted into 4LO.
The message turns off as soon as the conditions
that caused the message to be displayed are
no longer present.
3-61