brakes HUMMER H3 2007 Owners Manual

Make sure the shift lever is fully in PARK (P)
before starting the engine. Your vehicle has an
automatic transmission shift lock control system.
You must fully apply your regular brakes rst
and then press the shift lever button before you
can shift from PARK (P) when the ignition key is in
ON. If you cannot shift out of PARK (P), ease
pressure on the shift lever and push the shift lever
all the way into PARK (P) as you maintain
brake application. Then press the shift lever button
and move the shift lever into another gear. See
Shifting Out of Park (P) (Automatic Transmission)
on page 119
REVERSE (R):Use this gear to back up.
Notice:Shifting to REVERSE (R) while your
vehicle is moving forward could damage
the transmission. The repairs would not be
covered by your warranty. Shift to
REVERSE (R) only after your vehicle is
stopped.
To rock your vehicle back and forth to get out of
snow, ice, or sand without damaging your
transmission, seeIf Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow on page 286.NEUTRAL (N):In this position, your engine does
not connect with the wheels. To restart when
you are already moving, use NEUTRAL (N) only.
{CAUTION:
Shifting into a drive gear while your
engine is running at high speed is
dangerous. Unless your foot is rmly on
the brake pedal, your vehicle could move
very rapidly. You could lose control and
hit people or objects. Do not shift into a
drive gear while your engine is running at
high speed.
Notice:Shifting out of PARK (P) or
NEUTRAL (N) with the engine running at high
speed may damage the transmission. The
repairs would not be covered by your warranty.
Be sure the engine is not running at high
speed when shifting your vehicle.
107

DRIVE (D):This position is for normal driving.
It provides the best fuel economy for your vehicle.
If you need more power for passing, and you are:
Going less than about 35 mph (55 km/h), push
your accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more, push
the accelerator all the way down.
Downshifting the transmission in slippery road
conditions could result in skidding, see “Skidding”
underLoss of Control on page 249.
DRIVE (D) can be used when towing a trailer.
You may want to shift the transmission to
THIRD (3) or, if necessary, a lower gear if the
transmission shifts too often under heavy loads
and/or hilly conditions.
THIRD (3):This position is also used for normal
driving. However it reduces vehicle speed
more than DRIVE (D) without using your brakes.
You might choose THIRD (3) instead of DRIVE (D)
when driving on hilly, winding roads, when
towing a trailer, so there is less shifting between
gears and when going down a steep hill.SECOND (2): This position reduces vehicle speed
even more than THIRD (3) without using your
brakes. You can use SECOND (2) on hills. It can
help control your speed as you go down steep
mountain roads, but then you would also want to
use your brakes off and on.
FIRST (1): This position reduces vehicle speed
even more than SECOND (2) without using
your brakes. You can use it on very steep hills, or
in deep snow or mud. If the shift lever is put in
FIRST (1) while the vehicle is moving forward, the
transmission will not shift into rst gear until the
vehicle is going slowly enough.
Notice:Spinning the tires or holding the
vehicle in one place on a hill using only
the accelerator pedal may damage the
transmission. The repair will not be covered
by your warranty. If you are stuck, do not spin
the tires. When stopping on a hill, use the
brakes to hold the vehicle in place.
108

Cruise control will not work if your parking brake is
set, or if the master cylinder brake uid level is low.
If you apply your brakes, the cruise control
shuts off.
{CAUTION:
Cruise control can be dangerous where
you cannot drive safely at a steady speed.
So, do not use your cruise control on
winding roads or in heavy traffic.
Cruise control can be dangerous on
slippery roads. On such roads, fast
changes in tire traction can cause
excessive wheel slip, and you could lose
control. Do not use cruise control on
slippery roads.
The cruise control disengages, if the vehicle has the
Traction Control System (TCS) and it begins to limit
wheel spin. SeeTraction Control System (TCS) on
page 241. When road conditions allow you to safely
use it again, you can turn cruise control back on.
Setting Cruise Control
{CAUTION:
If you leave your cruise control on when
you are not using cruise, you might hit a
button and go into cruise when you do not
want to. You could be startled and even
lose control. Keep the cruise control switch
off until you want to use cruise control.
1. Move the cruise control switch to on.
2. Get up to the speed desired.
3. Press in the set button at the end of the
lever and release it.
4. Take your foot off the accelerator pedal.
The cruise symbol
on the instrument
panel comes on
when the cruise
control is engaged.
160

{CAUTION:
Your brake system may not be working
properly if the brake system warning
light is on. Driving with the brake system
warning light on can lead to an accident.
If the light is still on after you have pulled
off the road and stopped carefully, have
the vehicle towed for service.
Anti-Lock Brake System
Warning Light
With the Anti-Lock Brake
System (ABS), this light
will come on briey when
you start your engine
to show it is working.
Then it will turn off.
This is normal.
If the light stays on, or comes on when you are
driving, your vehicle needs service. If the regular
brake system warning light is not on, you still
have brakes, but you do not have anti-lock brakes.
If the regular brake system warning light is also
on, you do not have anti-lock brakes and there
is a problem with your regular brakes. SeeBrake
System Warning Light on page 182.
The ABS warning light should come on briey
when you turn the ignition key to ON. If the light
does not come on then, have it xed so it will
be ready to warn you if there is a problem.
183

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. The messages are
displayed for four seconds each.
Some messages may not require immediate
action, but you should press and release the trip
odometer reset stem to acknowledge that you
received the messages and to clear them from the
display. Each message must be acknowledged
individually.
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.
AC (Air Conditioning) OFF
This message displays when the engine coolant
temperature is too high and the air conditioning in
your vehicle needs to be turned off. SeeEngine
Overheating on page 338andClimate Control
System on page 170for more information.
This message displays along with the ENG HOT
message.
ABS (Anti-Lock Brake System) FAULT
This message displays if there is a problem
with the Anti-Lock Brake System (ABS). Check the
ABS as soon as possible and have your vehicle
serviced by your dealer. SeeBrakes on page 347
andAnti-Lock Brake System Warning Light on
page 183for more information. Press and release
the reset stem to acknowledge the message
and clear it from the display.
196

BRAKES
This message displays if there is a problem with
the brakes. Check the brakes as soon as possible
and have your vehicle serviced by your dealer.
SeeBrakes on page 347andBrake System
Warning Light on page 182for more information.
Press and release the reset stem to acknowledge
the message and clear it from the display.
CHANGE OIL
This message displays when the oil needs to be
changed. Check the oil in your vehicle as soon
as possible and have your vehicle serviced by
your dealer. SeeEngine Oil on page 323
andScheduled Maintenance on page 429for
more information. Press and release the reset
stem to acknowledge the message and clear
it from the display.
DOORS
This message displays when one or more of
the doors is ajar. Check all the doors on your
vehicle to make sure they are closed. The
message clears from the display after all of
the doors are closed.
ENG (Engine) HOT
This message displays when the engine coolant
temperature is hot. Check the engine coolant
temperature gage. SeeEngine Coolant
Temperature Gage on page 185. Have your
vehicle serviced by your dealer as soon as
possible if you suspect the engine is overheating.
SeeEngine Overheating on page 338for more
information.
FLUID
This message displays if the brake uid is low.
Check the brake uid as soon as possible
and have your vehicle serviced by your dealer.
SeeBrakes on page 347for more information.
Press and release the reset stem to acknowledge
the message and clear it from the display.
197

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 241.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 314.
Braking
SeeBrake System Warning Light on page 182.
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.
238

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 ever loses electrical power while you
are driving, brake normally but do not pump the
brakes. If you do, the pedal may get harder to push
down. If your vehicle loses electrical power, 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, the brake pedal will
be harder to push, and you may experience longer
pedal travel.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 314Anti-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 ABS, this warning
light will stay on.
SeeAnti-Lock Brake
System Warning
Light on page 183.
239

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 wheel.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.
240

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 and also reduces engine power. You may
feel or hear the system working, but this is normal.
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 159.
241