transmission HUMMER H2 2004 Owner's Manual

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 a while, 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.
3-38

TIGHTEN FUEL CAP
If the vehicle’s fuel cap is not tightened properly this
message may appear along with the check engine light
on the instrument panel. SeeMalfunction Indicator
Lamp on page 3-38. Reinstall the fuel cap, making sure
to fully install the cap. SeeFilling Your 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 will allow fuel to evaporate into
the atmosphere. A few driving trips with the cap properly
installed should turn the light and message off.
CHECK WASHER FLUID
If the washer uid level is low, this message will appear
on the DIC. Adding washer uid will clear the message.
Pressing the select button will clear it from the DIC
display. This message will clear itself after 10 seconds
until the next ignition cycle.
TRACTION ACTIVE
When the traction control system has detected that any
of the vehicle’s wheels are slipping, the traction
control system will activate and this message will appear
on the DIC. SeeTraction Control System (TCS) on
page 4-9for more information.
TRANSMISSION HOT
If the transmission uid temperature becomes high, the
message center will display this message.
When the transmission enters the protection mode, you
may notice a change in the transmission shifting
patterns. When the transmission uid temperature
returns to normal, the display will turn off and the
transmission shifting patterns will return to normal.
Notice:If you drive your vehicle while the
transmission uid is overheating and the
transmission temperature warning is displayed on
the instrument panel cluster and/or DIC, you
can damage the transmission. This could lead to
costly repairs that would not be covered by
your warranty. Do not drive your vehicle with
overheated transmission uid or while transmission
temperature warning is displayed.
3-59

The following situations can cause the transmission to
operate at higher temperatures:
Towing a trailer
Hot outside air temperatures
Hauling a large or heavy load
Low transmission uid level
High transmission uid level
Restricted air ow to the radiator and the auxiliary
transmission oil cooler (if equipped).
A temporary solution to hotter transmission operating
temperatures may be to let the transmission cool down.
If the transmission is operated at higher temperatures
on a frequent basis, seeScheduled Maintenance
on page 6-4for the proper transmission maintenance
intervals.
TRANS HOT IDLE ENGINE
If the transmission uid gets hot, this message will
appear on the DIC along with a continuous chime.
Driving with the transmission uid temperature high can
cause damage to the vehicle. Stop the vehicle and
let it idle to allow the transmission to cool. This message
will clear and the chime will stop when the uid
temperature reaches a safe level.
DRIVER DOOR AJAR
If the driver’s door is not fully closed and the vehicle is
in a drive gear, this message will appear on the
display and you will hear a chime. Stop and turn off the
vehicle, check the door for obstacles, and close the
door again. Check to see if the message still appears on
the DIC. Pressing the select button will clear it from
the DIC display.
3-60

Remember: Anti-lock does not change the time you
need to get your foot up to the brake pedal or always
decrease stopping distance. If you get too close to
the vehicle in front of you, you will not have time to apply
your brakes if that vehicle suddenly slows or stops.
Always leave enough room up ahead to stop, even
though you have anti-lock brakes.
Using Anti-Lock
Do not pump the brakes. Just hold the brake pedal
down rmly and let anti-lock work for you. You may feel
the brakes vibrate, or you may notice some noise,
but this is normal.
Braking in Emergencies
With anti-lock, you can steer and brake at the same
time. In many emergencies, steering can help you more
than even the very best braking.
Traction Control System (TCS)
Your vehicle has a Traction Control System (TCS) that
limits wheel spin. This is especially useful in slippery
road conditions. The system operates only if it senses
that any of the wheels are spinning or beginning to lose
traction. When this happens, the system applies the
brakes to limit wheel spin.
The Traction Control System may operate on dry roads
under some conditions. When this happens, you
may notice a reduction in acceleration or a pumping
sound. This is normal and doesn’t mean there’s a
problem with your vehicle. Examples of these conditions
include hard acceleration in a turn, an abrupt upshift
or downshift of the transmission or driving on
rough roads.
If your vehicle is in cruise control when the TCS begins
to limit wheel spin, the cruise control will automatically
disengage. When road conditions allow you to safely
use it again, you may re-engage the cruise control. See
“Cruise Control” underTurn Signal/Multifunction
Lever on page 3-6.
4-9

Brake and Throttle Operation
Techniques for Off-Road Driving
For logs, walls, rocks, severe ditches, hills, sand, etc.
1. Bring the vehicle to a complete stop. Do not
overspeed the engine.
2. Select the proper transmission and transfer case
gear range; usually FIRST (1) gear, 4LO LOCK for
such obstacles.
3. If wheel spin is experienced, maintain steady
throttle, with your foot off the brake pedal, to
allow the TCS to control the wheel spin. TCS will
not operate if the brakes are applied, even slightly.
4. If wheel spin can not be controlled by the system,
fully press the brake pedal with your left foot so all
wheel spin is halted.
5. Back away from the obstacle such that a new
approach can be tried.
6. As the rst wheel crosses the obstacle, be prepared
to modulate the brake and throttle to maintain
control and avoid tire drop-off from obstacles.
Repeat the controlled process for the other wheels.For mounds, washouts, loose up-hill slopes,
ditches, etc.
4-27

When wheel spin occurs as the vehicle is moving, the
driver may notice a slight shaking or shuddering of
the vehicle. This should be stopped as soon as possible
to prevent damage to vehicle components. This is the
indication that a loss of traction is occuring on this
terrain. The operator should:
1. Reduce throttle, brake wheels.
2. Assess the terrain properly and adjust vehicle
speed and gear ranges accordingly: 4HI position
for higher speeds and 4LO LOCK for more torque
and lower speeds. Transmission FIRST (1) gear
is generally recommended.
3. Apply slight pressure to the brake when the shaking
or shuddering sensation is felt, keeping the vehicle
moving in a controlled manner.
4. Be prepared to modulate the brake and throttle
through the adverse terrain.
Getting Familiar with Off-Road Driving
It is a good idea to practice in an area that is safe
and close to home before you go into the wilderness.
Off-road driving does require some new and different
skills. Here is what we mean.
Tune your senses to different kinds of signals. Your
eyes, for example, need to constantly sweep the terrain
for unexpected obstacles. Your ears need to listenfor unusual tire or engine sounds. With your arms,
hands, feet and body, you will need to respond
to vibrations and vehicle bounce.
Controlling your vehicle is the key to successful off-road
driving. One of the best ways to control your vehicle
is to control your speed. Here are some things to keep
in mind. At higher speeds:
you approach things faster and you have less time
to scan the terrain for obstacles.
you have less time to react.
you have more vehicle bounce when you drive over
obstacles.
you will need more distance for braking, especially
since you are on an unpaved surface.
{CAUTION:
When you are driving off-road, bouncing and
quick changes in direction can easily throw
you out of position. This could cause you to
lose control and crash. So, whether you’re
driving on or off the road, you and your
passengers should wear safety belts.
4-28

Crossing Obstacles
Approach Angle — a Key to Mobility.If you encounter a
large dip in the terrain, do not enter straight on; enter
at an angle — 15° minimum approach (A), 75° maximum
approach angle (B). For very large dips, ditches or
small washes, coast in, using the engine as a brake
(transmission and transfer case lowest gears). Then, use
the low ranges in the transmission and transfer case
to power out.Roll Your Tires Over Large
Rocks.Do not straddle
large rocks; drive
over them, letting the tire
envelop the rock. The
tread of the tire is thicker
and tougher than the
sidewall of the tire and is
more resilient to impact
than underbody
components.
4-30

Log Crossing.Using the proper technique, the
HUMMER H2 will cross logs up to 10 inches (25.4 cm) in
diameter. Approach the log at approximately a 15° angle
(A) with the transmission in FIRST (1) and the transfer
case in 4LO LOCK and “walk” the HUMMER H2 over,
one tire at a time. As with all obstacles, face your tires
perpendicular to the object for best traction and tire life. It
may be necessary to modulate your brake pedal and
accelerator to avoid spin-out. Ease the vehicle down from
the log with your brake.Driving on Off-Road Hills
Off-road driving often takes you up, down or across a
hill. Driving safely on hills requires good judgment
and an understanding of what your vehicle can and can
not do. There are some hills that simply can not be
driven, no matter how well built the vehicle.
{CAUTION:
Many hills are simply too steep for any vehicle.
If you drive up them, you will stall. If you drive
down them, you can not control your speed. If
you drive across them, you will roll over. You
could be seriously injured or killed. If you have
any doubt about the steepness, do not drive
the hill.
4-31

Approaching a Hill
When you approach a hill, you need to decide if it is
one of those hills that is just too steep to climb, descend
or cross. Steepness can be hard to judge. On a very
small hill, for example, there may be a smooth, constant
incline with only a small change in elevation where
you can easily see all the way to the top. On a large hill,
the incline may get steeper as you near the top, but
you may not see this because the crest of the hill
is hidden by bushes, grass or shrubs.
Here are some other things to consider as you approach
a hill.
Is there a constant incline, or does the hill get
sharply steeper in places?
Is there good traction on the hillside, or will the
surface cause tire slipping?
Is there a straight path up or down the hill so you
will not have to make turning maneuvers?
Are there obstructions on the hill that can block
your path (boulders, trees, logs or ruts)?
What is beyond the hill? Is there a cliff, an
embankment, a drop-off, a fence? Get out and walk
the hill if you do not know. It is the smart way to
nd out.
Is the hill simply too rough? Steep hills often have
ruts, gullies, troughs and exposed rocks because
they are more susceptible to the effects of erosion.
Driving Uphill
Once you decide you can safely drive up the hill, you
need to take some special steps.
Use transmission and transfer case low gear and
get a rm grip on the steering wheel.
Get a smooth start up the hill and try to maintain
your speed. Do not use more power than you
need, because you do not want your wheels to start
spinning or sliding.
Let the traction system work to control any wheel
slippage. TC2 is designed to allow moderate
wheel spin with some capability to dig in and power
up the hill.
4-32

Q:What should I do if my vehicle stalls, or
is about to stall, and I can not make it up
the hill?
A:If this happens, there are some things you should
do, and there are some things you must not do.
First, here is what youshoulddo:
Push the brake pedal to stop the vehicle and
keep it from rolling backwards. Also, apply the
parking brake.
If your engine is still running, shift the transmission
to REVERSE (R), release the parking brake, and
slowly back down the hill in REVERSE (R).
If your engine has stopped running, you will need to
restart it. With the brake pedal pressed and the
parking brake still applied, shift the transmission to
PARK (P) and restart the engine. Then, shift to
REVERSE (R), release the parking brake, and
slowly back down the hill as straight as possible in
REVERSE (R).
As you are backing down the hill, put your left hand
on the steering wheel at the 12 o’clock position.
This way, you will be able to tell if your wheels are
straight and maneuver as you back down. It is
best that you back down the hill with your wheels
straight rather than in the left or right direction.
Turning the wheel too far to the left or right
will increase the possibility of a rollover.Here are some things youmust notdo if you stall, or
are about to stall, when going up a hill.
Never attempt to prevent a stall by shifting into
NEUTRAL (N) to “rev-up” the engine and regain
forward momentum. This will not work. Your vehicle
will roll backwards very quickly and you could go
out of control.
Instead, apply the regular brake to stop the vehicle.
Then apply the parking brake. Shift to
REVERSE (R), release the parking brake, and
slowly back straight down.
Never attempt to turn around if you are about to
stall when going up a hill. If the hill is steep
enough to stall your vehicle, it is steep enough to
cause you to roll over if you turn around. If you can
not make it up the hill, you must back straight
down the hill.
4-34