2007 HUMMER H2 Owners Manual

But the ability to drive is affected well below a BAC
of 0.10 percent. Research shows that the driving
skills of many people are impaired at a BAC
approaching 0.05 percent, and that the effects are
worse at night. All drivers are impaired at BAC
levels above 0.05 percent. Statistics show that the
chance of being in a collision increases sharply for
drivers who have a BAC of 0.05 percent or above.
A driver with a BAC level of 0.06 percent has
doubled his or her chance of having a collision. At a
BAC level of 0.10 percent, the chance of this driver
having a collision is 12 times greater; at a level of
0.15 percent, the chance is 25 times greater!
The body takes about an hour to rid itself of the
alcohol in one drink. No amount of coffee or
number of cold showers will speed that up. “I will
be careful” is not the right answer. What if
there is an emergency, a need to take sudden
action, as when a child darts into the street?
A person with even a moderate BAC might
not be able to react quickly enough to avoid the
collision.There is something else about drinking and driving
that many people do not know. Medical research
shows that alcohol in a person’s system can make
crash injuries worse, especially injuries to the
brain, spinal cord, or heart. This means that when
anyone who has been drinking — driver or
passenger — is in a crash, that person’s chance
of being killed or permanently disabled is
higher than if the person had not been drinking.
{CAUTION:
Drinking and then driving is very
dangerous. Your reexes, perceptions,
attentiveness, and judgment can be
affected by even a small amount of
alcohol. You can have a serious — or
even fatal — collision if you drive after
drinking. Please do not drink and drive
or ride with a driver who has been
drinking. Ride home in a cab; or if you
are with a group, designate a driver
who will not drink.
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Control of a Vehicle
You have three systems that make your vehicle go
where you want it to go. They are the brakes, the
steering, and the accelerator. All three systems
have to do their work at the places where the tires
meet the road.
Sometimes, as when you are driving on snow or
ice, it is easy to ask more of those control systems
than the tires and road can provide. That means
you can lose control of your vehicle. SeeTraction
Control System (TCS) on page 309.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 392.
Braking
SeeBrake System Warning Light on page 211.
Braking action involves perception time and
reaction time.
First, you have to decide to push on the brake
pedal. That is perception time. Then you have to
bring up your foot and do it. That is reaction time.
Average reaction time is about three-fourths of a
second. But that is only an average. It might be less
with one driver and as long as two or three seconds
or more with another. Age, physical condition,
alertness, coordination, and eyesight all play a part.
So do alcohol, drugs, and frustration. But even in
three-fourths of a second, a vehicle moving at
60 mph (100 km/h) travels 66 feet (20 m). That
could be a lot of distance in an emergency, so
keeping enough space between your vehicle and
others is important.
And, of course, actual stopping distances vary
greatly with the surface of the road, whether it is
pavement or gravel; the condition of the road,
whether it is wet, dry, or icy; tire tread; the
condition of the brakes; the weight of the vehicle;
and the amount of brake force applied.
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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.
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Let us say the road is wet and you are driving
safely. Suddenly, an animal jumps out in front of
you. You slam on the brakes and continue braking.
Here is what happens with ABS:
A computer senses that wheels are slowing down.
If one of the wheels is about to stop rolling, the
computer will separately work the brakes at each
front wheel and at both rear wheels.ABS can change the brake pressure faster than
any driver could. The computer is programmed to
make the most of available tire and road
conditions. This can help you steer around the
obstacle while braking hard.
As you brake, your computer keeps receiving
updates on wheel speed and controls braking
pressure accordingly.
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Remember: ABS 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 ABS.
Using ABS
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 ABS, 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. SeeCruise Control on page 183.
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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

Locking Rear Axle
The locking rear axle can give your vehicle
additional traction from the rear wheels when
traveling in off-road situations such as mud, snow,
sand, steep hills and uneven terrain.
The button used to turn
this feature on or off is
located above the
transfer case buttons
to the right of the
steering wheel.
To lock the rear axle, do the following:
1. Place the transfer case in the Four-Wheel-Low
Lock mode. This is the only mode which will
allow the rear axle to lock. SeeFull-Time
Four-Wheel Drive on page 128for more
information regarding the transfer case and
Four-Wheel-Low-Lock mode.
2. Press the button with the vehicle stopped or
moving less than 2 mph (3 km/h).You must wait for the light in the button to stop
ashing and remain illuminated before the
rear axle is locked.
Notice:If you try to lock the rear axle while
your vehicle is stuck and the tires are spinning,
you could damage your vehicle’s drivetrain.
The repairs would not be covered by your
warranty. Always lock the rear axle before
attempting situations and/or navigating terrain
which could possibly cause the vehicle to
become stuck.
The locking rear axle will be disengaged when the
vehicle’s speed is greater than 20 mph (32 km/h), if
the vehicle’s battery is low and/or the transfer case
is shifted out of Four-Wheel-Low-Lock mode.
Notice:If you lock the rear axle while driving
on pavement, you could damage your
vehicle’s drivetrain. The repairs would not be
covered by your warranty. Do not use the
locking rear axle on pavement. If you need
four-wheel drive when traveling on pavement,
use only 4HI.
311

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.
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