Control of a Vehicle Braking
You
have three systems that make your vehicle go where Braking action involves perception time and
you want it to go. They are the brakes, the steering and reaction time.
the accelerator. All three systems have to do their work
First, you have to decide to push on the brake pedal.
at the places where the tires meet the road.
That’s perception time. Then you have to bring up
your fo.ot and do
it. That’s reaction time.
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 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; and the condition
of your brakes.
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 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 b’etween
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, 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.
ABS
INOP
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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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 sudd’enly slows or stops. Alwayssleave
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 ‘‘L’ow Traction Light”
in the
Index
naction Control, System
(Option: LTl VS Engine) I
Your vehicle may have a traction control system that
limits wheel spin. This is especially usefulin slippery
road conditions.
The system operates only if it senses that
one or both of
the rear wheels are spinning or beginning
to lose traction. When
this happens, the system works the
rear brakes and reduces engine, power (by closing the
throttle and managing engine spark) to limit wheel spin.
LOW
TRAC
This light will come on
when YQLU traction control
system is limiting wheel
spin. See “Low Traction
Light”
in the Index. You
may feel or hear the system
working, but this is normal.
The traction control system may operate on dry roads
under some conditions, and you may notice a reduction in
acceleration when this happen,€, This is normal and doesn’t
mean there’s
a problem with your vehicle. Examples of
fhese conditions include a hard acceleration in a turn, or an
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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. Unless you have traction control and the
system is on, 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 courqe, the posted speeds are
based on good weather and road conditions. Under less
favorable conditions you’ll want
to go slower.
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 Pontiac 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
L 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
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 Pontiac’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 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.
Let’s
review what driving experts say about what E your vehicle starts to slide, ease your foot off the
happens when the
three control systems (brakes, steering accelerator
pedal and quickly steer the way you want the
and acceleration) don’t have enough friction where the vehicle to
go. If you start steering quickly enough, your
tires meet the road to do what the driver has asked. vehicle may straighten
out. Always be ready for a
constantly seek an escape route or area of less danger. second
skid if it occurs.
. .-
. -- . r- _.. In any emergency, don’t give up. Keep trying to steer and ..
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Wet brakes can cause accidents. They won’t work
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.
!.
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.
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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.
e Keep your vehicle in good shape. Check all fluid
levels and
also the brakes, tires, cooling system and
transmission. 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.
I
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.
Know how to go uphill. You may want to shift down
to a lower gear. The lower gears help cool your engine
and transmission, and you can climb the hill better.
0 In hilly terrain, you may want to switch to the
PERFORMANCE 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.
could be something in your lane, like a stalled car or
an accident.
As you go over the top of a hill, be al’ert. There
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four anti-lock brakes improve your vehicle’s stability
when you make a hard stop on a slippery road. Even
though you have the anti-lock braking system, you’ll
want to begin stopping sooner than you would on dry
pavement. See “Anti-Lock” in the Index.
Allow greater following distance on apy slippery road.
Watch for slippery spots. The road might be fine
until you’hit
a spot that’s covered with ice. On an
otherwise clear road, ice patches may appear in
shaded areas where the sun can’t reach: around
clumps
of trees, behind buildings or under bridges.
Sometimes the surface
of a curve or anoverpass may
remain icy when the surrounding roads are clear.
If
you see a patch of ice ahead of you, brake before you
are on it.
Try not to brake while you’re actually on
the ice, and avoid sudden steering maneuvers.
If You’re Caught in a Blizzard
If you are stopped by heavy snow, you could be in a
serious situation. You.should probably stay with your
vehicle unless
you know for sure that you are near help
and you can hike through the snow. Here are some
things to do to summon help and keep yourself and
your
passengers safe:
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