Control of a Vehicle Braking
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. 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.
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. 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 314
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 bralung. 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 a little. This is normal.
ANTI -
LOCK
If there’s a problem with the
anti-lock brake system, this
warning light will stay on or
flash. See “Anti-Lock
Brake System Warning
Light” in the Index.
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than any driver could. The computer
is programmed to
The
anti-lock system can change the
brake pressure faster
mc&e the most of available tire and
road conditions.
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 front wheel and at the
rear wheels. 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
and let anti-lock work for
you. You may feel the system
working, or
you may notice some noise, but this is normal.
LOW TRAC
When your anti-lock system
is adjusting brake pressure
to help avoid a braking skid,
this light will come on. See
“Anti-Lock Brake System
Active Light” in
the Index.
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.
Magnasteer TM (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.
A lot of the “driver lost control” accidents mentioned on
the news happen on curves. Here’s why:
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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.
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 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 “drive” 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 Buick can perform very well in emergencies like
these. First apply your brakes. (See “Braking in
Emergencies” 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 vehicre 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.
following driver
to get ahead of you. Perhaps you
can ease
a little to the right.
If you’re being passed, make it easy for the
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 Buick’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.
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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’t, try to slow down before you hit them.
Wet brakes can cause accidents. They won’t 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.
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If you drive regularly in steep country, or if you’re
planning to visit there, here are some tips that can make
your trips safer and more enjoyable.
0 Keep your vehicle in good shape. Check all fluid
levels and also the brakes, tires, cooling system
and transaxle. These parts can work hard on
mountain roads.
0 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.
If you don’t shift down, your brakes could
get
so hot that they wouldn’t 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.
- __
Coasting downhill in NEUTRAL (N) or with the
ignition
off is dangerous. Your brakes will have to
do all the work of slowing down. They could get so
hot that they wouldn’t work well. You would then
have poor braking or even none going down
a hill.
You could crash. Always have your engine running
and your vehicle
in gear when you go downhill.
0
0
0
0
Know how to go uphill. You may want to shift down
to a lower gear. The lower gears help cool your engine
and transaxle, and you can climb the hill better.
Stay in your own lane when driving on two-lane
roads
in hills or mountains. Don’t swing wide or cut
across
the center of the road. Drive at speeds that let
you stay in your own lane.
As you go over the top of a hill, be alert. There could be
something in your lane, like a stalled car or
an accident.
You may see highway signs on mountains that warn
of
special problems. Examples are long grades, passing or
no-passing zones, a falling rocks area or winding
roads. Be alert to these and take appropriate action.
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