brake Oldsmobile Aurora 1997 s Owner's Guide

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.
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.
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.
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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
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 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, and you may even notice that your brake
pedal moves a little. This is normal.
LOCK
ANT‘- (@)
If there’s a problem with the
anti-lock brake system, this
warning light will stay on.
See “Anti-Lock Brake
System Warning Light” 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 front wheel and at the
rear wheels. 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
and let anti-lock work for you. You may hear a motor or
clicking noise during a hard stop, but this is normal.
Traction Control System
Your vehicle 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.
TRACTION ACTIVE
This light will come on
when your traction control
system is limiting wheel
spin. See “Traction Control
System Active Light” in
the Index.
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
re-engage the cruise control. (See “Cruise Control”
in
the Index.)
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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
Your vehicle is equipped with GM Magnasteer TM, a
steering system that continuously adjusts the effort you
feel when steering at all vehicle speeds. It provides ease
when parking yet a firm, solid feel at highway speeds.
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: 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 “Traction Control System” 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
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 Aurora 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. 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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Do not get too close to the vehicle you want to pass
while you’re awaiting an opportunity. For one thing,
following too closely reduces your area of vision,
especially if you’re following a larger vehicle. Also,
you won’t have adequate space if the vehicle
ahead suddenly slows or stops. Keep back a
reasonable distance.
When it looks like a chance to pass is coming up,
start to accelerate but stay in the right lane and don’t
get
too close. Time your move so you will be
increasing speed
as the time comes to move into the
other lane.
If the way is clear to pass, you will have a
“running start” that more than makes up for the
distance you would lose by dropping back. And if
something happens to cause you to cancel your pass,
you need only slow down and drop back again and
wait for another opportunity.
0 If other cars are lined up to pass a slow vehicle, wait
your turn. But take care that someone isn’t trying to
pass you as you pull out to pass the slow vehicle.
Remember to glance over your shoulder and check
the blind spot.
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.)
0 Try not to pass more than one vehicle at a time on
two-lane roads. Reconsider before passing the
next vehicle.
0 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.
0 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.
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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
“overdriving” those conditions. But skids are
always possible.
The
three types of skids correspond to your Aurora’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.
Remember: Any traction control system helps avoid
only the acceleration skid. If
your traction control 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
-- 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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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.
I /! CAUTION:
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.
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.
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.
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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.
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Know how to go uphill. Drive in the highest gear possible.
In hilly terrain, you may want to switch to the
POWER mode for better performance.
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.