2004 BUICK LESABRE brakes

Anti-lock Brake System (ABS)
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, 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 is a problem with
the anti-lock brake system,
this warning light will
stay on. SeeAnti-Lock
Brake System Warning
Light on page 3-38.
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 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 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 anti-lock brakes.
Using Anti-Lock
Do not 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
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.
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Traction Control System (TCS)
Your vehicle may have 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.
You may feel or hear the system working, but this is
normal.
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” under
Turn Signal/Multifunction Lever on page 3-7.This light should come on
briey when you start the
engine. If it stays on or
comes on while you
are driving, there is a
problem with your traction
control system.
SeeTraction Control System (TCS) Warning Light on
page 3-39. When this warning light is on, 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 “Rocking Your Vehicle To Get It Out”
underIf You Are Stuck: In Sand, Mud, Ice or Snow on
page 4-30.
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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 — if you can stop
in time. But sometimes you can not; there is not
room. That is the time for evasive action — steering
around the problem.
Your vehicle can perform very well in emergencies like
these. First apply your brakes.
SeeBraking 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 us review what driving experts say about what
happens when the three control systems (brakes, steering
and acceleration) do not have enough friction where
the tires meet the road to do what the driver has asked.
In any emergency, do not 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
are not 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 have the traction control system, remember: It
helps avoid only the acceleration skid. If you do not have
traction control, 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.
If you have Stabilitrak
®, you may see the STABILITY
SYSTEM ACTIVE message on the Driver Information
Center. See “Stability System Active Message”
underDIC Warnings and Messages on page 3-49.
Of course, traction is reduced when water, snow, ice,
gravel or other material is on the road. For safety,
you will 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 “mirrored surface” — and slow
down when you have any doubt.
Remember: Any anti-lock brake system (ABS) helps
avoid only the braking skid.
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The heavier the rain, the harder it is to see. Even if your
windshield wiper blades are in good shape, a heavy
rain can make it harder to see road signs and
traffic signals, pavement markings, the edge of the road
and even people walking.
It is wise to keep your windshield wiping equipment in
good shape and keep your windshield washer tank lled
with washer uid. Replace your windshield wiper
inserts when they show signs of streaking or missing
areas on the windshield, or when strips of rubber start to
separate from the inserts.
Driving too fast through large water puddles or even
going through some car washes can cause problems,
too. The water may affect your brakes. Try to avoid
puddles. But if you can not, try to slow down before you
hit them.
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{CAUTION:
Wet brakes can cause accidents. They will not
work as well in a quick stop and may cause
pulling to one side. You could lose control of
the vehicle.
After driving through a large puddle of water
or a car wash, apply your brake pedal lightly
until your brakes work normally.
Hydroplaning
Hydroplaning is dangerous. So much water can build up
under your tires that they can actually ride on the
water. This can happen if the road is wet enough and
you are going fast enough. When your vehicle is
hydroplaning, it has little or no contact with the road.Hydroplaning does not happen often. But it can if your
tires do not have much tread or if the pressure in one or
more is low. It can happen if a lot of water is standing
on the road. If you can see reections from trees,
telephone poles or other vehicles, and raindrops
“dimple” the water’s surface, there could be
hydroplaning.
Hydroplaning usually happens at higher speeds. There
just is not a hard and fast rule about hydroplaning.
The best advice is to slow down when it is raining.
Driving Through Deep Standing Water
Notice:If you drive too quickly through deep
puddles or standing water, water can come in
through your engine’s air intake and badly damage
your engine. Never drive through water that is
slightly lower than the underbody of your vehicle. If
you can not avoid deep puddles or standing
water, drive through them very slowly.
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Hill and Mountain Roads
Driving on steep hills or mountains is different from
driving in at or rolling terrain.If you drive regularly in steep country, or if you are
planning to visit there, here are some tips that can make
your trips safer and more enjoyable.
Keep your vehicle in good shape. Check all uid
levels and also the brakes, tires, cooling system
and transaxle. These parts can work hard on
mountain roads.
Know how to go down hills. The most important
thing to know is this: let your engine do some of
the slowing down. Shift to a lower gear when you go
down a steep or long hill.
{CAUTION:
If you do not shift down, your brakes could get
so hot that they would not work well. You
would then have poor braking or even none
going down a hill. You could crash. Shift down
to let your engine assist your brakes on a
steep downhill slope.
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