2004 PONTIAC GRAND PRIX brakes

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 wheel.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.
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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
®rmly and let anti-lock work for you. You may feel a
slight brake pedal pulsation or notice some noise,
but this is normal.
Braking in Emergencies
At some time, nearly every driver gets into a situation
that requires hard braking.
If you have anti-lock, you can steer and brake at the
same time. However, if you don't have anti-lock,
your ®rst reaction Ð to hit the brake pedal hard andhold it down Ð may be the wrong thing to do. Your
wheels can stop rolling. Once they do, the vehicle can't
respond to your steering. Momentum will carry it in
whatever direction it was headed when the wheels
stopped rolling. That could be off the road, into the very
thing you were trying to avoid, or into traffic.
If you don't have anti-lock, use a ªsqueezeº braking
technique. This will give you maximum braking while
maintaining steering control. You can do this by pushing
on the brake pedal with steadily increasing pressure.
In an emergency, you will probably want to squeeze
the brakes hard without locking the wheels. If you hear
or feel the wheels sliding, ease off the brake pedal.
This will help you retain steering control. If you
dohave
anti-lock, it's different. See ªAnti-Lock Brake Systemº
in this section.
In many emergencies, steering can help you more than
even the very best braking.
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Traction Control System (TCS)
If your vehicle has the 3800 supercharged V6 engine
it has a traction control system that limits wheel
spin. This is especially useful in slippery road conditions.
The system operates only if it senses that one or both
of the front wheels are spinning or beginning to lose
traction. When this happens, the system works the front
brakes and reduces engine power to limit wheel spin.
This symbol will appear on
the DIC screen when the
system is active, along with
the TRACTION CONTROL
ACTIVE message.
You may feel or hear the system working, but this is
normal.
When the traction control
system is not working, this
symbol will appear on the
instrument panel cluster.This symbol, along with
the message TRACTION
CONTROL OFF will
also display in the DIC
for three seconds when
the traction control system
is not active.
When these symbols and messages appear on the
instrument panel and the Driver's Information Center
(DIC), the system will not limit wheel spin. Adjust your
driving accordingly.
The traction control system automatically comes on
whenever you start your vehicle. To limit wheel spin,
especially in slippery road conditions, you should always
leave the system on. But you can turn the traction
control system off if you ever need to. You should turn
the system off if your vehicle ever gets stuck in
sand, mud or snow and rocking the vehicle is required.
See ªRocking Your Vehicle to Get It Outº under
If You Are Stuck: In Sand, Mud, Ice or Snow on
page 4-32.
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To turn the system off,
press the traction control
button located on the
console.
If the system is limiting wheel spin when you press the
button the system will turn off instantly. You can
turn the system back on at any time by pressing the
button again.
If your vehicle is in cruise control when the traction
control system begins to limit wheel spin, the cruise
control will automatically disengage. When road
conditions allow you to safely use it again, you may
reengage the cruise control. See
Cruise Control Lever
on page 3-8.
Enhanced Traction System (ETS)
If your vehicle has the 3800 V6 engine and anti-lock
brakes, your vehicle may have an Enhanced Traction
System (ETS) that limits wheel spin. This is especially
useful in slippery road conditions. The system operates
only if it senses that one or both of the front wheels
are spinning or beginning to lose traction. When
this happens, the system reduces engine power and
may also upshift the transaxle to limit wheel spin.
This symbol will appear on
the Driver Information
Center (DIC) when your
Enhanced Traction System
is limiting wheel spin.
If your vehicle is in cruise control when the enhanced
traction system 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. See
Cruise Control Lever
on page 3-8.
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StabilitrakžPlus System
Your vehicle may be equipped with a vehicle stability
enhancement system called StabilitrakžPlus. It is
an advanced computer controlled system that assists
you with directional control of the vehicle in difficult
driving conditions.
Stabilitrak
žPlus comes on whenever the vehicle is
started. It activates when the computer senses a
discrepancy between your intended path and the
direction the vehicle is actually traveling. Stabilitrak
ž
Plus selectively applies braking pressure at any one of
the vehicle's brakes to help steer the vehicle in the
direction which you are steering.
This symbol, along with
the STABILITY CONTROL
ACTIVE message will
appear on the Driver
Information Center (DIC).See
DIC Warnings and Messages on page 3-65.
You may also hear a noise or feel vibration in the brake
pedal. This is normal. Continue to steer the vehicle in
the direction you want it to go.
If there is a problem
detected with Stabilitrak
ž
Plus, this symbol along
with the SERVICE
STABILITY SYSTEM
warning message will be
displayed on the Driver
Information Center (DIC).
See
DIC Warnings and Messages on page 3-65. When
this message is displayed, the system is not operational.
Driving should be adjusted accordingly.
If your vehicle is in cruise control when Stabilitrak
žPlus
activates, the cruise control will automatically disengage.
When road conditions allow you to safely use it again,
you may reengage the cruise control. See
Cruise Control
Lever on page 3-8for more information.
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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.
Variable Effort Steering
If your vehicle has this steering system, the system
provides less steering effort for parking and when driving
at speeds below 20 mph (32 km/h). Steering effort will
increase at higher speeds for improved road feel.
Steering Tips
Driving on Curves
It's important to take curves at a reasonable speed.
A lot of the ªdriver lost controlº accidents mentioned on
the news happen on curves. Here's 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's no traction, inertia will keep the
vehicle going in the same direction. If you've ever tried to
steer a vehicle on wet ice, you'll 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're
in a curve, speed is the one factor you can control.Suppose you're steering through a sharp curve.
Then you suddenly apply the brakes. Both control
systems Ð steering and braking Ð have to do their
work where the tires meet the road. Unless you have
four-wheel anti-lock brakes, adding the hard braking can
demand too much of those places. You can lose control.
The same thing can happen if you're steering through a
sharp curve and you suddenly accelerate. Those two
control systems Ð steering and acceleration Ð can
overwhelm those places where the tires meet the road
and make you lose control. See
Traction Control System
(TCS) on page 4-10orEnhanced Traction System (ETS)
on page 4-11.
What should you do if this ever happens? Ease up on
the brake or 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'll 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 ªdriveº 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.
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Steering in Emergencies
There are times when steering can be more effective than
braking. For example, you come over a hill and ®nd a
truck stopped in your lane, or a car suddenly pulls out
from nowhere, or a child darts out from between parked
cars and stops right in front of you. You can avoid
these problems by braking Ð if you can stop in time.
But sometimes you can't; there isn't room. That's the
time for evasive action Ð steering around the problem.
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.
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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 ªoverdrivingº
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 you do not have the Enhanced Traction System or the
Traction Control System, or if the system is off, then
an acceleration skid is also 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.
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 Ð such as enough water, ice or packed snow on
the road to make a ªmirrored surfaceº Ð and slow down
when you have any doubt.
If you have the anti-lock braking system, remember:
It helps avoid only the braking skid. If you do not have
anti-lock, then in a braking skid (where the wheels
are no longer rolling), release enough pressure on the
brakes to get the wheels rolling again. This restores
steering control. Push the brake pedal down steadily
when you have to stop suddenly. As long as the wheels
are rolling, you will have steering control.
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