service HUMMER H2 2009 Owner's Manual

If the airbag readiness light stays on after the vehicle is
started or comes on while driving, the airbag system
may not work properly. Have the vehicle serviced
by your dealer/retailer.
{CAUTION:
If the airbag readiness light stays on after the
vehicle is started or comes on while driving, it
means the airbag system might not be working
properly. The airbags in the vehicle might not
inate in a crash, or they could even inate
without a crash. To help avoid injury, have the
vehicle serviced right away.
Airbag Off Light
If the vehicle has an airbag on-off switch in the glove
box, it also has a passenger airbag status indicator
located in the overhead console.
When the vehicle is started, the passenger airbag status
indicator will light ON and OFF, or the symbol for on
and off, will light for several seconds as a system check.
Then, after several more seconds, the status indicator
ON or OFF, or either the on or off symbol, will light to
let you know the status of the right front passenger
frontal airbag.United States
Canada
3-33

{CAUTION:
If the airbag readiness light ever comes on and
stays on, it means that something may be wrong
with the airbag system. For example, the right
front passenger airbag could inate even though
the airbag on-off switch is turned off.
To help avoid injury to yourself or others, have the
vehicle serviced right away. SeeAirbag Readiness
Light on page 3-32for more information, including
important safety information.
If the word ON or the on symbol is lit, it means that
the right front passenger frontal airbag is enabled (may
inate). SeeAirbag Off Switch on page 1-76for more
information, including important safety information.
If, after several seconds, both status indicator lights
remain on, or if there are no lights at all, there may
be a problem with the lights or the airbag on-off switch.
See your dealer/retailer for service.
Charging System Light
This light comes on briey
when the ignition key is
turned to START, but the
engine is not running, as a
check to show it is working.
If it does not, have the vehicle serviced by your
dealer/retailer.
The light should go out once the engine starts. If it stays
on, or comes on while driving, there could be a problem
with the charging system. A charging system message
in the Driver Information Center (DIC) can also appear.
SeeDIC Warnings and Messages on page 3-56for
more information. This light could indicate that there are
problems with a generator drive belt, or that there is an
electrical problem. Have it checked right away. If the
vehicle must be driven a short distance with the light
on, turn off accessories, such as the radio and air
conditioner.
3-35

Voltmeter Gage
When the 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 can
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 can also read low during the fuel
economy mode.Readings in the low warning zone can 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 full power. If there
is a problem with the battery charging system, this light
comes on or the SERVICE BATTERY CHARGING
SYSTEM DIC message displays. SeeDIC Warnings
and Messages on page 3-56andCharging System
Light on page 3-35for more information.
3-36

Brake System Warning Light
With the ignition on, the brake system warning light
comes on when the parking brake is set. If the vehicle is
driven with the parking brake engaged, a chime sounds
when the vehicle speed is greater than 5 mph (8 km/h).
The vehicle’s hydraulic brake system is divided into
two parts. If one part is not working, the other part
can still work and stop the vehicle. For good braking,
both parts need to be working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have the brake system
inspected right away.
This light can also come on due to low brake uid.
SeeBrakes on page 5-38for more information.This light comes on briey when the ignition key is
turned to ON/RUN. If it does not come on then, have it
xed so it is ready to warn if there is a problem.
{CAUTION:
The brake system might not be working properly if
the brake system warning light is on. Driving with
the brake system warning light on can lead to a
crash. If the light is still on after the vehicle has
been pulled off the road and carefully stopped,
have the vehicle towed for service.
If the light comes on while driving, pull off the road and
stop carefully. The pedal might be harder to push or
might go closer to the oor. It can take longer to stop.
If the light is still on, have the vehicle towed for service.
SeeTowing Your Vehicle on page 4-50.
United States
Canada
3-37

Antilock Brake System (ABS)
Warning Light
For vehicles with
the Antilock Brake
System (ABS), this light
comes on briey when
the engine is started.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
If the ABS light stays on, turn the ignition off. If the
light comes on while driving, stop as soon as it is safely
possible and turn the ignition off. Then start the engine
again to reset the system. If the ABS light stays on, or
comes on again while driving, the vehicle needs service.
If the regular brake system warning light is not on, the
vehicle still has brakes, but not antilock brakes. If the
regular brake system warning light is also on, the vehicle
does not have antilock brakes and there is a problem with
the regular brakes. SeeBrake System Warning Light on
page 3-37.
For vehicles with a Driver Information Center (DIC),
seeDIC Warnings and Messages on page 3-56for all
brake related DIC messages.
StabiliTrak®Indicator Light
For vehicles with the
StabiliTrak®system, this
light comes on briey while
starting the engine.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
If the light comes on and stays on while driving, there
could be a problem with the StabiliTrak
®system and the
vehicle might need service. When this warning light is
on, the StabiliTrak
®system is off and does not limit
wheel spin.
The light ashes if the system is active and is working
to assist the driver with directional control of the
vehicle in difficult driving conditions.
SeeStabiliTrak
®System on page 4-6for more
information.
3-38

When the Light Flashes First and Then is
On Steady
This indicates that there could be a problem with the
Tire Pressure Monitor System. The light ashes for about
a minute and stays on steady for the remainder of the
ignition cycle. This sequence repeats with every ignition
cycle. SeeTire Pressure Monitor System on page 5-64
for more information.
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 ensures that emissions are at acceptable levels
for the life of the vehicle, helping to produce a cleaner
environment.
This light should come on
when the ignition is on, but
the engine is not running,
as a check to show it
is working. If it does not,
have the vehicle serviced
by your dealer/retailer.If the check engine light comes on and stays on, while
the engine is running, this indicates that there is an
OBD II problem and service is required.
Malfunctions often are indicated by the system before
any problem is apparent. Being aware of the light
can prevent more serious damage to the vehicle.
This system assists the service technician in correctly
diagnosing any malfunction.
Notice:If the vehicle is continually driven with
this light on, after a while, the emission controls
might not work as well, the 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 the vehicle warranty.
Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of
the vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect the vehicle’s emission
controls and can cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by the vehicle warranty. This
could also result in a failure to pass a required
Emission Inspection/Maintenance test. See
Accessories and Modifications on page 5-3.
3-40

This light 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 the vehicle.
Diagnosis and service might be required.
To prevent more serious damage to the vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
If towing a trailer, reduce the amount of cargo being
hauled as soon as it is possible.
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 key off, wait at least 10 seconds, and restart
the engine. If the light is still ashing, follow the previous
steps and see your dealer/retailer for service as soon
as possible.
Light On Steady:An emission control system
malfunction has been detected on the vehicle.
Diagnosis and service might be required.An emission system malfunction might be corrected by
doing the following:
Make sure the fuel cap is fully installed. SeeFilling
the Tank on page 5-8. 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.
If the vehicle has been driven through a deep puddle
of water, the 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.
Make sure to fuel the vehicle with quality fuel. Poor
fuel quality causes the engine not to run as efficiently
as designed and can cause: stalling after start-up,
stalling when the vehicle is changed into gear,
misring, hesitation on acceleration, or stumbling
on acceleration. These conditions might go away
once the engine is warmed up.
If one or more of these conditions occurs, change the
fuel brand used. It will require at least one full tank of
the proper fuel to turn the light off.
SeeGasoline Octane on page 5-5.
If none of the above have made the light turn off, your
dealer/retailer can check the vehicle. The dealer/retailer
has the proper test equipment and diagnostic tools to
x any mechanical or electrical problems that might have
developed.
3-41

Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
might begin programs to inspect the emission control
equipment on the vehicle. Failure to pass this inspection
could prevent getting a vehicle registration.
Here are some things to know to help the vehicle pass
an inspection:
The vehicle will not pass this inspection if the check
engine light is on with the engine running, or if the
key is in ON/RUN and the light is not on.
The vehicle will not pass this inspection if the
OBD II (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 the battery has recently been replaced
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 this has been done and the
vehicle still does not pass the inspection for lack of
OBD II system readiness, your dealer/retailer can
prepare the vehicle for inspection.
Oil Pressure Gage
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches re.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.United States
Canada
3-42

Notice:Lack of proper engine oil maintenance
can damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow
the maintenance schedule in this manual for
changing engine oil.
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 can vary with engine speed, outside
temperature and oil viscosity, but readings above
the low pressure zone indicate the normal operating
range. When the oil pressure reaches the low pressure
zone, the OIL PRESSURE LOW STOP ENGINE
message appears in the Driver Information Center (DIC).
SeeDIC Warnings and Messages on page 3-56and
Engine Oil on page 5-15for more information.
A reading in the low pressure zone can be caused
by a dangerously low oil level or some other problem
causing low oil pressure. Check the oil as soon as
possible.Oil Pressure Light
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches re.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice:Lack of proper engine oil maintenance
can damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow
the maintenance schedule in this manual for
changing engine oil.
This light comes on briey while starting the engine.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally
the indicator light then goes off.
3-43

Low Fuel Warning Light
This light, under the fuel
gage, comes on briey
while the engine is being
started.
This light and a chime comes on when the fuel tank is
low on fuel. The Driver Information Center also displays
a “FUEL LEVEL LOW” message. SeeDIC Warnings
and Messages on page 3-56for more information.
When fuel is added this light and message should go
off. If it does not, have the vehicle serviced by your
dealer/retailer.
Driver Information Center (DIC)
Your vehicle has a Driver Information Center (DIC).
The DIC displays information about your vehicle.
It also displays warning messages if a system
problem is detected.
All messages will appear in the DIC display located
below the tachometer in the instrument panel cluster.
The DIC comes on when the ignition is on. After a short
delay, the DIC will display the information that was last
displayed before the engine was turned off.
For the displays available using DIC buttons, see “DIC
Operation and Displays (Using DIC Buttons)” later in this
section andDIC Vehicle Customization on page 3-64.
For the displays available using the trip odometer reset
stem, see “DIC Operation and Displays (Using Trip
Odometer Reset Stem)” later in this section.
3-46