1999 BUICK CENTURY brake

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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'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.
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 (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.

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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. 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.
Anti-Lock Brakes (ABS)
Your vehicle has anti-lock brakes (ABS). ABS is an
advanced electronic braking system that will help
prevent a braking skid.
When you start your engine, or when you 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, and you may even notice that your
brake pedal moves or pulses a little. This is normal.
If there's a problem with the
anti
-lock brake system, this
warning light will stay on.
See ªAnti
-Lock Brake
System Warning Lightº in
the Index.

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Here's how anti-lock works. Let's say the road is wet.
You're driving safely. Suddenly an animal jumps out in
front of you.
You slam on the brakes. 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.
You can 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
firmly and let anti
-lock work for you. You may feel a
slight brake pedal pulsation or notice some noise, but
this is normal.
Enhanced Traction System
Your vehicle is equipped with 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 light will come on
when your Enhanced
Traction System is limiting
wheel spin. See ªEnhanced
Traction System Active
Lightº in the Index.
You may feel or hear the system working, but this
is normal.
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
reengage the cruise control. (See ªCruise Controlº in
the Index.)
The Enhanced Traction System operates in THIRD (3)
and OVERDRIVE (
). If you are in THIRD (3), the
system can upshift the transaxle to OVERDRIVE (
).
The Enhanced Traction System is turned off in
SECOND (2) or FIRST (1) gear. See ªAutomatic
Transaxleº in the Index.

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When the system is on, this
warning light will come on
to let you know if there's
a problem.
See ªEnhanced Traction System Warning Lightº in the
Index. When this warning light is on, the system will not
limit wheel spin. Adjust your driving accordingly.
To limit wheel spin, especially in slippery road
conditions, you should always leave the Enhanced
Traction System on. But you can turn the system off if
you ever need to. (You should turn the system off if your
vehicle ever gets stuck in sand, mud, ice or snow. See
ªRocking Your Vehicleº in the Index.)
To turn the system off, your gear shift lever must be in
FIRST (1) or SECOND (2) gear. See ªRocking Your
Vehicleº in the Index. When you turn the system off, the
Enhanced Traction System warning light will come on
and stay on. If the Enhanced Traction System is limiting
wheel spin when you turn the system off, the warning
light will come on
-- but the system won't turn off right
away. It will wait until there's no longer a current need
to limit wheel spin. Also, if you set the parking brake,
the system will turn off.You can turn the system back on at any time by shifting
to OVERDRIVE (
) or THIRD (3). The Enhanced
Traction System warning light should go off.
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.
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.
Magnetic Variable Effort Steering

(If Equipped)
This steering system provides lighter steering effort for
parking and when driving at low speeds. 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.

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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 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. Refer to
ªEnhanced Traction Systemº in the Index.
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 arebased 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.
Steering in Emergencies
There are times when steering can be more effective than
braking. For example, you come over a hill and find 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
-- if you can stop in time. But
sometimes you can't; there isn't room. That's the time for
evasive action
-- steering around the problem.
Your vehicle can perform very well in emergencies like
these. First apply your brakes. (See ªBraking in
Emergenciesº earlier in this section.) 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.

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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
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 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 and an acceleration skid are 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.

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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
-- such as enough water, ice or packed snow on
the road to make a ªmirrored surfaceº
-- and slow
down when you have any doubt.
Remember: Any anti
-lock brake system (ABS) helps
avoid only the braking skid.
Driving at Night
Night driving is more dangerous than day driving. One
reason is that some drivers are likely to be impaired
-- by
alcohol or drugs, with night vision problems, or by fatigue.