brake GMC SIERRA DENALI 2003 Owner's Manual

SERVICE AIRBAG
If there is a problem with the air bag system, this
message will be displayed on the
DIC. Have a qualified
technician inspect the system for problems. Pressing
the select button will acknowledge this message
and clear it from the
DIC display.
SERVICE BRAKE SYSTEM
If there is a problem with the brake system, this
message will be displayed on the
DIC. If this message
appears, stop as soon as possible and turn
off the
vehicle. Restart the vehicle and check for the message
on the
DIC display. If the message is still displayed,
or appears again when you begin driving, the brake
system needs service.
SERVICE BRAKE BOOSTER
If your vehicle has vaccum assist power brakes, this
message will be displayed on the
DIC when there is a
problem with the Supplemental Brake Assist system.
If the message is displayed immediately after starting
the vehicle or the message appears while driving,
your Supplemental Brake Assist system needs service.
See
Brake System Warning Light on page 3-34.
Your brake system may not be working
properly if the SERVICE BRAKE BOOSTER
message is displayed.
If the brake system warning light is also on,
you should have the vehicle towed for service. See “Brake System Warning Light”
in the
Index.
If the brake system warning light
isn’t on, you
still have brakes, but the supplemental brake
assist system may not operate properly.
In the
event of a vacuum
loss, you may not have
vacuum power assist for braking. The brake pedal will
be harder to push and it will take
longer to stop.
If you continue to drive with
this message displayed it can lead to a crash.
Have the brake system serviced as soon as
possible.
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REDUCED BRAKE POWER
If your vehicle has vacuum assist power brakes, this
message will be displayed and you may notice that the
brake pedal is harder to push and it will take longer
to stop. You may also hear a motor running and feel a
slight vibration in the brake pedal or steering wheel
when you apply or release the brake pedal even
if your
foot is not on the brake pedal. This indicates that the
Supplemental Brake Assist system is working to
maintain braking power.
If you are braking lightly, you
may not notice any difference in the operation
of
your brakes.
This message may also be displayed for brief periods
if
you are driving at higher elevations and are pumping
your brakes or braking hard. The message may
clear after you’ve lifted your foot from the accelerator
pedal an allowed the vehicle to coast
in gear or after you
have driven down to a lower elevation. This is a
normal operation of your brake system and does not
require that the brake system be serviced. However,
if
the message does not clear, your brake system
needs service. While the message is displayed you will
notice that the brake pedal is harder to push and
it
will take longer to stop. See Brake System Warning
Light
on page 3-34.
Your brake system may not be working
properly if the REDUCED BRAKE POWER
message is displayed. If this message comes
on and stays on while driving, pull
off the road
and stop carefully. The brake pedal will be
harder to push and
it will take longer to stop.
If the message is no longer displayed after you
have pulled
off the road and stopped, you can
continue driving.
However, if the message is still displayed, or if
it comes on again when you are driving, there
is a problem with your brake system. If you
continue to drive with this message displayed
it can lead to an accident. You should have the
vehicle towed for service. Also, see Brake
System Warning Light in the Index.
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Your Driving, the Road, and
Your Vehicle
Defensive Driving
The best advice anyone can give about driving is: Drive
defensively.
Please start with a very important safety device in your
vehicle: Buckle up. See
Safety Belts: They Are for
Everyone
on page 1-8.
Defensive driving really means “be ready for anything.”
On city streets, rural roads or freeways, it means
“always expect the unexpected.”
Assume that pedestrians or other drivers are going to
be careless and make mistakes. Anticipate what
they might do. Be ready for their mistakes.
Rear-end collisions are about the most preventable of
accidents. Yet they are common. Allow enough following
distance. It’s the best defensive driving maneuver, in
both city and rural driving. You never know when
the vehicle in front of you is going to brake or turn
suddenly.
Defensive driving requires that a driver concentrate on
the driving task. Anything that distracts from the driving
task
- such as concentrating on a cellular telephone call,
reading, or reaching for something on the floor
- makes proper defensive driving
more difficult and can even
cause
a collision, with resulting injury. Ask a passenger to
help do things like this, or pull off the road in a safe place
to do them yourself. These simple defensive driving
techniques could save your life.
Drunken Driving
Death and injury associated with drinking and driving is
a national tragedy. It’s the number one contributor to
the highway death toll, claiming thousands of victims
every year.
Alcohol affects four things that anyone needs to drive
a
vehicle:
Judgment
Muscular Coordination
Vision
Attentiveness.
Police records show that almost half of all motor
vehicle-related deaths involve alcohol. In most cases,
these deaths are the result of someone who was
drinking and driving. In recent years, more than
16,000 annual motor vehicle-related deaths have been
associated with the use of alcohol, with more than
300,000 people injured.
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There’s something else about drinking and driving that
many people don’t 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.
Drinmnn,,d and then driving
is verb ..angerous.
Your reflexes, perceptions, attentiveness and
judgement 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 don’t drink and drive or ride with a
driver who has been drinking. Ride home
in a
~ cab; or if you’re with a group, designate a
i driver who will not drink.
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’re driving on snow or ice, it’s
easy to ask more
of those control systems than the
tires and road can provide. That means you can lose
control
of your vehicle.
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‘\, Braking
Braking action involves perception time and
reaction time.
First, you have to decide to push on the brake pedal.
That’s
perception time. Then you have to bring up your
foot and do it. That’s
reaction time.
Average reaction time is about 3/4 of a second. But
that’s 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
3/4 of a second, a vehicle moving
at
60 mph (I00 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’s pavement
or gravel); the condition of the road (wet, dry, icy); tire
tread; the condition of your brakes; the weight of
the vehicle and the amount of brake force applied. 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. Your brakes may not have time to cool
between hard stops. Your 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 engine ever stops while you’re driving, brake
normally but don’t pump your brakes. If you do,
the pedal may get harder
to push down. If your 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.
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Anti-lock Brake System
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on. This is normal.
If there’s a problem with
the anti-lock brake system,
this warning light will stay on. See
Anti-Lock
Brake
System Warning
Light on page
3-35.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system.
If there’s a DRP problem,
both the Brake and ABS warning lights will come on
accompanied by a 10-second chime. The lights
and chime will come on each time the ignition is turned
on until the problem
is repaired. See your dealer for
service. Let’s
say the road is wet and you’re driving safely.
Suddenly, an animal jumps out in front of you.
You slam
on the brakes and continue braking. Here’s 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.
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The anti-lock system 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. Remember:
Anti-lock doesn’t 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 won’t 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
Don’t pump the brakes. Just hold the brake pedal down
firmly 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.
Locking Rear Axle
If your vehicle has this feature, your locking rear axle
can give you additional traction on snow, mud, ice, sand
or gravel. It works like a standard axle most of the
time, but when one of the rear wheels has no traction
and the other does, this feature will allow the wheel with
traction to move the vehicle.
4-8

Your vehicle can perform very well in emergencies like
these. First apply your brakes.
See
Braking on page 4-6. It is better to remove as much
speed as you can from a possible collision. Then
steer around the problem, to the left
or right depending
on the space available.
An emergency like this requires close attention and a
quick decision. If you are holding the steering wheel at
the recommended
9 and 3 o’clock positions, you
can turn it a full 180 degrees very quickly without
removing either hand. But you have to act fast, steer
quickly, and just as quickly straighten the wheel
once you have avoided the object. The
fact that such emergency situations are always
possible is a good reason
to practice defensive driving
at all times and wear safety belts properly.
QUADRASTEERTM
The QUADRASTEERTM System has a control and
diagnostic module that monitors and records current
system status and operational information.
If your vehicle is equipped with the 4 Wheel Steer
system it has the ability to steer the vehicle with all four
wheels.
Once the
4 Wheel Steer mode is selected, it is
recommended
to leave the vehicle in this mode at all
times, and during all driving and weather conditions.
You can select this mode at any speed, however,
if you
are turning the system will not engage until the turn
is complete.
The 4 Wheel Steer system is equipped with three
different driving modes:
Two wheel steering (2)
Four wheel steering (4)
Four wheel steering with a trailer mode (q )
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a
Check your mirrors, glance over your shoulder and
start your left lane change signal before moving out
of the right lane
to pass. When you are far enough
ahead of the passed vehicle to see its front in your
inside mirror, activate your right lane change signal
and move back into the right lane. (Remember that
if
your right outside mirror is convex, the vehicle you
just passed may seem
to be farther away from you
than it really is.)
Try not to pass more than one vehicle at a time on
two-lane roads. Reconsider before passing the next
vehicle.
Don’t overtake a slowly moving vehicle too rapidly.
Even though the brake lamps are not flashing, it may
be slowing down or starting to turn.
If you’re being passed, make
it easy for the following
driver to get ahead
of you. Perhaps you can ease a
little
to the right.
Loss of Control
Let’s review what driving experts say about what
happens when the three control systems (brakes,
steering and acceleration) don’t have enough friction
where the tires meet the road to do what the driver
has asked.
In any emergency, don’t give up. Keep trying
to steer
and constantly seek an escape route or area of
less danger.
Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking reasonable
care suited
to existing conditions, and by not
“overdriving” those conditions. But skids are always
possible.
The three types of skids correspond to your vehicle’s
three control systems. In the braking skid, your wheels
aren’t rolling. In the steering or cornering skid, too
much speed or steering
in a curve causes tires to slip
and lose cornering force. And in the acceleration
skid, too much throttle causes the driving wheels
to spin.
A cornering skid is best handled by easing your foot
off
the accelerator pedal.
If your vehicle starts to slide, ease your foot off the
accelerator pedal and quickly steer the way you want
the vehicle
to go. If you start steering quickly enough,
your vehicle may straighten out. Always be ready
for a second skid
if it occurs.
Of course, traction is reduced when water, snow, ice,
gravel or other material
is on the road. For safety, you’ll
want to slow down and adjust your driving
to these
conditions.
It is important to slow down on slippery
surfaces because stopping distance will be longer and
vehicle control more limited.
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While driving on a surface with reduced traction, try
your best to avoid sudden steering, acceleration
or braking (including engine braking by shifting to a
lower gear). Any sudden changes could cause the tires
to slide. You may not realize the surface is slippery
until your vehicle
is skidding. Learn to recognize warning
clues
- such as enough water, ice or packed snow
on the road to make a “mirrored surface”
- and slow
down when you have any doubt.
Remember: Any anti-lock brake system (ABS) helps
avoid only the braking skid.
Operating Your All-Wheel-Drive
Vehicle
Off Paved Roads
Many of the same design features that help make your
vehicle responsive on paved roads during poor
weather conditions
- features like the locking rear axle
and all-wheel drive
- help make it much better
suited for off-road use than a conventional passenger
car. Its higher ground clearance also helps your vehicle
step over some off-road obstacles. But your vehicle
doesn’t have features like special underbody shielding
and a transfer case low gear range, things that are
usually thought necessary for extended or sever off-road
service. This guide
is for operating your vehicle off
paved roads.
Also, see Braking on page 4-6.
Off-road driving can be great fun. But it does have
some definite hazards. The greatest of these is
the terrain itself.
“Off-roading” means you’ve left the great North American\
road system behind. Traffic lanes aren’t marked.
Curves aren’t banked. There are no road signs.
Surfaces can be slippery, rough, uphill or downhill. In
short, you’ve gone right back to nature.
Off-road driving involves some new skills. And that’s
why it’s very important that
you read this guide.
You’ll find many driving tips and suggestions. These will
help make your off-road driving safer and more
enjoyable.
Before You Go Off-Roading
There are some things to do before you go out. For
example, be sure to have all necessary maintenance
and service work done. Check to make sure all
underbody shields (if
so equipped) are properly
attached.
Is there enough fuel? Is the spare tire fully
inflated? Are the fluid levels up where they should be?
What are the local laws that apply to off-roading
where you’ll be driving?
If you don’t know, you should
check with law enforcement people in the area. Will you
be on someone’s private land? If
so, be sure to get
the necessary permission.
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