2007 HUMMER H2 engine

TIGHTEN FUEL CAP
This message may display along with the check
engine light on the instrument panel cluster if
the vehicle’s fuel cap is not tightened properly.
SeeMalfunction Indicator Lamp on page 215.
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 allows fuel to
evaporate into the atmosphere. A few driving trips
with the cap properly installed should turn the
light and message off.
TRACTION ACTIVE
This message displays when the Traction Control
System (TCS) is active. This happens when
the TCS has detected that any of the vehicle’s
wheels are slipping. SeeTraction Control
System (TCS) on page 309for more information.
TRANS (Transmission) HOT IDLE
ENGINE
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 the
transmission temperature warning is displayed.
This message displays and a continuous chime
sounds if the transmission uid in the vehicle gets
hot. 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 clears and the chime stops
when the uid temperature reaches a safe
level. SeeTransmission Temperature Gage on
page 213.
232

While your vehicle is parked:
Familiarize yourself with all of its controls.
Familiarize yourself with its operation.
Set up your audio system by presetting your
favorite radio stations, setting the tone, and
adjusting the speakers. Then, when driving
conditions permit, you can tune to your favorite
radio stations using the presets and steering
wheel controls if the vehicle has them.
Notice:Before adding any sound equipment to
your vehicle, such as an audio system, CD
player, CB radio, mobile telephone, or two-way
radio, make sure that it can be added by
checking with your dealer. Also, check federal
rules covering mobile radio and telephone
units. If sound equipment can be added, it is
very important to do it properly. Added sound
equipment may interfere with the operation of
your vehicle’s engine, radio, or other systems,
and even damage them. Your vehicle’s systems
may interfere with the operation of sound
equipment that has been added.Notice:The chime signals related to safety
belts, parking brake, and other functions of
your vehicle operate through the radio/
entertainment system. If that equipment is
replaced or additional equipment is added to
your vehicle, the chimes may not work. Make
sure that replacement or additional equipment
is compatible with your vehicle before installing
it. SeeAccessories and Modifications on
page 392.
Your vehicle has a feature called Retained
Accessory Power (RAP). With RAP, the audio
system can be played even after the ignition
is turned off. SeeRetained Accessory
Power (RAP) on page 121for more information.
242

Avoid needless heavy braking. Some people drive
in spurts — heavy acceleration followed by
heavy braking — rather than keeping pace with
traffic. This is a mistake. The brakes may not have
time to cool between hard stops. The brakes
will wear out much faster if you do a lot of heavy
braking. If you keep pace with the traffic and
allow realistic following distances, you will
eliminate a lot of unnecessary braking. That means
better braking and longer brake life.
If your vehicle’s engine ever stops while you are
driving, brake normally but do not pump the
brakes. If you do, the pedal may get harder to
push down. If the engine stops, you will still have
some power brake assist. But you will use it
when you brake. Once the power assist is used
up, it may take longer to stop and the brake pedal
will be harder to push.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 392.Anti-Lock Brake System (ABS)
Your vehicle has the Anti-Lock Brake System
(ABS), an advanced electronic braking system
that will help prevent a braking skid.
When you start your engine and begin to drive
away, ABS will check itself. You may hear a
momentary motor or clicking noise while this test
is going on. This is normal.
If there is a problem
with the ABS, this
warning light will stay
on. SeeAnti-Lock Brake
System Warning Light
on page 212.
307

Another feature of this system is the Traction
Control 2 (TC2) mode. TC2 should be selected for
improved traction and system performance
when the vehicle is on loose surfaces such as
deep sand or mud.
To enter this mode,
press the TC2 button
located on the
instrument panel to the
right of the steering
wheel.
TC2 only operates in the following transfer case
modes:
Four-Wheel-High Lock
Four-Wheel-Low Lock
Four-Wheel-Low Lock and Rear Axle Lock
SeeLocking Rear Axle on page 311for more
information on the rear axle lock.It will not operate in Four-Wheel-High. If the
TC2 button is pressed while in Four-Wheel High,
the light will ash for about 15 seconds and
then go out. The light should also come on briey
when you turn the ignition key to RUN; if it
doesn’t see your dealer for service.
If you restart your engine, the system reverts to
the standard TCS mode.
The traction off light will
come on when a
Traction Control System
or Anti-Lock Brake
System problem has
been detected and the
vehicle needs service.
SeeTraction Off Light on page 212.
When the traction off light is on, adjust your
driving accordingly.
The traction control system, as delivered from the
factory, will automatically come on whenever
you start your vehicle.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 392for more information.
310

Steering
Power Steering
If you lose power steering assist because the
engine stops or the system is not functioning,
you can steer but it will take much more effort.
Steering Tips
It is important to take curves at a reasonable speed.
A lot of the “driver lost control” accidents
mentioned on the news happen on curves.
Here is why:
Experienced driver or beginner, each of us is
subject to the same laws of physics when driving on
curves. The traction of the tires against the road
surface makes it possible for the vehicle to change
its path when you turn the front wheels. If there is
no traction, inertia will keep the vehicle going in the
same direction. If you have ever tried to steer a
vehicle on wet ice, you will understand this.
The traction you can get in a curve depends on
the condition of your tires and the road surface,
the angle at which the curve is banked, and your
speed. While you are in a curve, speed is the
one factor you can control.Suppose you are steering through a sharp curve.
Then you suddenly accelerate. Both control
systems — steering and acceleration — have to
do their work where the tires meet the road.
Adding the sudden acceleration can demand too
much of those places. You can lose control.
SeeTraction Control System (TCS) on page 309.
What should you do if this ever happens? Ease
up on the accelerator pedal, steer the vehicle the
way you want it to go, and slow down.
Speed limit signs near curves warn that you
should adjust your speed. Of course, the posted
speeds are based on good weather and road
conditions. Under less favorable conditions you will
want to go slower.
If you need to reduce your speed as you approach
a curve, do it before you enter the curve, while
your front wheels are straight ahead.
Try to adjust your speed so you can “drive”
through the curve. Maintain a reasonable, steady
speed. Wait to accelerate until you are out of
the curve, and then accelerate gently into
the straightaway.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 392.
312

Brake and Accelerator 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
rev 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 Traction Control System (TCS)
to control the wheel spin. TCS will not operate
if the brakes are applied, even slightly.
4. If wheel spin cannot 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 so that a new
approach can be tried.
6. As the rst wheel crosses the obstacle, be
prepared to alternate the brake and
accelerator pedal to maintain control and
avoid tire drop-off from obstacles. Repeat this
process for the other wheels.
For mounds, washouts, loose up-hill
slopes, ditches, etc.
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 occurring on this terrain.
The operator should:
1. Reduce speed and apply the brakes.
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 alternate between braking and
accelerating through the adverse terrain.
323

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 listen for 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 are driving on or off the road, you and
your passengers should wear safety belts.
Scanning the Terrain
Off-road driving can take you over many different
kinds of terrain. You need to be familiar with
the terrain and its many different features.
Here are some things to consider.
Surface Conditions:Off-roading can take you
over hard-packed dirt, gravel, rocks, grass, sand,
mud, snow, or ice. Each of these surfaces affects
the steering, acceleration, and braking of your
vehicle in different ways. Depending upon the kind
of surface you are on, you may experience
slipping, sliding, wheel spinning, delayed
acceleration, poor traction, and longer braking
distances.
324

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 cover
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.
326