2003 GMC YUKON DENALI brake

BATTERY
If the battery is not charging during operation, this
message will appear
on the DIG. Driving with this
problem could drain your battery. Have the electrical
system checked as soon as possible. Pressing the
select button will acknowledge this message and clear
it
from the DIC display.
SERVlCE AIR
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 SYSTE
If a problem occurs with the brake system, this message
will appear 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 4W
If a problem occurs with the all-wheel drive system? this
message will appear on the DIG.
If this message
appears, stop as
soon as possible and turn off the
vehicle. Restart the vehicle and check for the message
3-54
on the DIC display. If the message is still displayed, or
appears again when you begin driving, the four
wheel drive system needs service.
ONTROL
If a problem occurs with the suspension system, this
message will appear on the DIC.
If this message
appears, stop 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 suspension system needs
service.
TURN SIGNAL ON
If a turn signal is left on for 3/4 of a mile (1.2 km), this
message will appear on the display and you will hear a
chime. Move the turn signal/multifunction lever
to the
off position. Pressing the select button will acknowledge
this message and clear
it from the DIC display.
If the liftgate is open while the ignition is in
RUN, this
message will appear on the DIC and you will hear
a chime. Turn
off the vehicle and check the liftgate.
Restart the vehicle and check for the message on the
DlC display. Pressing the select button will acknowledge
this message and clear it from the
DIC display.

When the system activates, you may hear a noise or
feel a vibration in the brake pedal. This is normal. When
the STABILITY SYS ACTIVE message is on, you
should continue
to steer in the direction you want to go.
The system is designed
to help you in bad weather
or other difficult driving situations by making the most of
whatever road conditions will permit.
SERVICE STABILITY
If you ever see the SERVICE STABILITY message, it
means there may be a problem with your
StabiIitrak@system. If you see this message
try to reset
the system (stop; turn
off the engine; then start the
engine again). If the SERVICE STABILITY message still
comes on, it means there is a problem. You should
see your dealer for service. The vehicle is safe to drive,
however, you do not have the benefit of Stabilitrak@,
so reduce your speed and drive accordingly.
STABILITY SYS DISABLED
The STABILITY SYS DISABLED message will turn on
when you press the Stabilitrak@button, or when the
stability control has been automatically disabled. To limit
wheel spin and realize the full benefits of the stability
enhancement system, you should normally leave
Stabilitrak@on. However, you should turn Stabilitrak@off
if your vehicle gets stuck in sand, mud, ice or snow and you want to “rock”
your vehicle
to attempt to free it,
or if you are driving in extreme off-road conditions
and require more wheel spin. See If
You Are Stuck: In
Sand, Mud, Ice or
Snow on page 4-41. To turn the
Stabilitrak@system back on press the Stabilitrak@button
again. There are four conditions that can cause this
message
to appear. One condition is overheating, which
could occur
if Stabilitrak@activates continuously for an
extended period of time. The message will
also be
displayed
if the brake system warning light is on. See
Brake System Warning Light
on page 3-34. The
message could be displayed
if the stability system takes
longer than usual to complete its diagnostic checks
due to driving conditions. Also,
if an engine or vehicle
related problem has been detected, and the vehicle
needs service, the message will appear.
The message will turn off as soon as the conditions that
caused the message to be displayed are no longer
present.
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. See StabiIitrakO System
on page 4-9 for
more information.
3-57

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
1-25.
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:
0 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.

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.
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.
Drinking and
t n drivinc_ ; very -1ngerous.
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
driver who will not drink.
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.
4-5

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 314 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
(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’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.
4-6

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 IO-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.
4-7

As you brake, your computer keeps receiving updates
on wheel speed and controls braking pressure
accordingly.
4-8

Stabilitrak@ System
Your vehicle is equipped with Stabilitrak@, which
combines antilock brake, traction and stability control
systems and helps the driver maintain directional control
of the vehicle in most driving conditions.
When you first start your vehicle and begin
to drive
away, the system performs several diagnostic checks
to
insure there are no problems. You may hear or feel
the system working. This is normal and does not mean
there is a problem with your vehicle. The system
should initialize before the vehicle reaches
20 m.p.h.
(32 km/h). In some cases, it may take approximately two
miles
of driving before the system initializes.
If the system fails
to turn on or activate, the STABILITY
SYS DISABLED or SERVICE STABILITY message
will be displayed.
If the vehicle has gone through heavy
acceleration or braking or multiple turns during the
first two miles of driving after starting your vehicle, the
STABILITY
SYS DISABLED message may appear.
If this is the case, your vehicle does not need servicing.
You will need
to turn the vehicle off and then restart
it
to initialize Stabilitrak@.
If either message appears on the Driver Information
Center (DIC), and your vehicle hasn’t gone through hard
acceleration, braking
or multiple turns in the first two
miles of driving, your vehicle should be taken in
for service. The STABILITY SYS ACTIVE message will appear
on
the Driver Information Center (DIC) only when the
system is both on and activated. You may also feel or
hear the system working; this is normal. For more
information on
the stability messages, see Driver
Information Center (DIC) on page 3-43.
Stabilitrak@and part of the
traction control system can
be turned
off or back on
by pressing the
Stabilitrak@button located
on the instrument
When the system is turned
off, the traction off light will
illuminate, and the STABILITY SYS DISABLED
message will appear on the DIC to warn the driver that
both the stability system and part of the traction
control system are disabled. Your vehicle will still have
brake-traction control when Stabilitrak@is
off, but will
not be able
to use the engine speed management
system. See “Traction Control Operation” next for more
information.
4-9