brakes BUICK RANDEZVOUS 2007 User Guide

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
wheel.ABS 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.
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Remember: ABS 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 ABS.
Using ABS
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
At some time, nearly every driver gets into a
situation that requires hard braking.If you have ABS, you can steer and brake at the
same time. However, if you do not have ABS, your
rst reaction — to hit the brake pedal hard and hold
it down — may be the wrong thing to do. Your
wheels can stop rolling. Once they do, the vehicle
cannot respond to your steering. Momentum will
carry it in whatever direction it was headed when
the wheels stopped rolling. That could be off the
road, into the very thing you were trying to avoid, or
into traffic.
If you do not have ABS, use a “squeeze” braking
technique. This will give you maximum braking
while maintaining steering control. You can do this
by pushing on the brake pedal with steadily
increasing pressure.
In an emergency, you will probably want to
squeeze the brakes hard without locking the
wheels. If you hear or feel the wheels sliding, ease
off the brake pedal. This will help you retain
steering control. If you do have ABS, it is different.
SeeAnti-Lock Brake System (ABS) on page 307.
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.
The TRACTION ACTIVE message will come on
when the traction control system is limiting
wheel spin. SeeTraction Active Message on
page 227. 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.
SeeCruise Control on page 181.If this message comes on and stays on or comes
on while you are driving, there’s a problem
with your traction control system.
SeeService Traction System Warning Message
on page 226. When this warning message is
on, the TRAC OFF light will come on to remind
you that 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. SeeIf Your Vehicle is Stuck
in Sand, Mud, Ice, or Snow on page 331.
United StatesCanada
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Suppose you are steering through a sharp curve.
Then you suddenly apply the brakes. Both
control systems — steering and braking — have
to do their work where the tires meet the road.
Unless you have four-wheel anti-lock brakes,
adding the hard braking can demand too much of
those places. You can lose control.
The same thing can happen if you are steering
through a sharp curve and you suddenly
accelerate. Those two control systems — steering
and acceleration — can overwhelm those places
where the tires meet the road and make you lose
control. SeeTraction Control System (TCS) on
page 310.
What should you do if this ever happens? Ease up
on the brake or 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 will
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.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 354.
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 cannot; 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 306. 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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When it looks like a chance to pass is coming
up, start to accelerate but stay in the right lane
and do not 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.
If other vehicles are lined up to pass a slow
vehicle, wait your turn. But take care that
someone is not 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 vehicle’s 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 vehicle’s inside
mirror, activate the right lane change signal and
move back into the right lane. Remember thatyour vehicle’s passenger side 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.
Do not overtake a slowly moving vehicle too
rapidly. Even though the brake lamps are not
ashing, it may be slowing down or starting
to turn.
If you are 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 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.
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If you have the Anti-Lock Brake System (ABS),
remember: It helps avoid only the braking skid. If
you do not have ABS, then in a braking skid,
where the wheels are no longer rolling, release
enough pressure on the brakes to get the wheels
rolling again. This restores steering control.
Push the brake pedal down steadily when you
have to stop suddenly. As long as the wheels are
rolling, you will have steering control.
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.
Here are some tips on night driving.
Drive defensively.
Do not drink and drive.
Adjust the inside rearview mirror to reduce the
glare from headlamps behind you.
Since you cannot see as well, you may need
to slow down and keep more space between
you and other vehicles.
Slow down, especially on higher speed roads.
Your vehicle’s headlamps can light up only so
much road ahead.
In remote areas, watch for animals.
If you are tired, pull off the road in a safe
place and rest.
No one can see as well at night as in the daytime.
But as we get older these differences increase.
A 50-year-old driver may require at least twice as
much light to see the same thing at night as a
20-year-old.
What you do in the daytime can also affect your
night vision. For example, if you spend the
day in bright sunshine you are wise to wear
sunglasses. Your eyes will have less trouble
adjusting to night. But if you are driving, do not
wear sunglasses at night. They may cut down on
glare from headlamps, but they also make a
lot of things invisible.
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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 wiping equipment in
good shape and keep your windshield washer uid
reservoir 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.
{CAUTION:
Wet brakes can cause accidents. They
may 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.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 cannot, try
to slow down before you hit them.
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.
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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.
{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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{CAUTION:
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
would not 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 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.
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. Do not 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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If you do not have TCS, accelerate gently. Try not
to break the fragile traction. If you accelerate
too fast, the drive wheels will spin and polish the
surface under the tires even more.
Unless you have the Anti-Lock Brake System
(ABS), you will want to brake very gently, too. If
you do have ABS, seeAnti-Lock Brake System
(ABS) on page 307. ABS improves your vehicle’s
stability when you make a hard stop on a
slippery road. Whether you have ABS or not, you
will want to begin stopping sooner than you
would on dry pavement. Without ABS, if you feel
your vehicle begin to slide, let up on the brakes
a little. Push the brake pedal down steadily to get
the most traction you can.
Remember, unless you have ABS, if you brake so
hard that your wheels stop rolling, you will just
slide. Brake so your wheels always keep rolling
and you can still steer.
Whatever your braking system, allow greater
following distance on any slippery road.
Watch for slippery spots. The road might be
ne until you hit a spot that is covered with
ice. On an otherwise clear road, ice patches
may appear in shaded areas where the
sun cannot reach, such as around clumps oftrees, behind buildings, or under bridges.
Sometimes the surface of a curve or an
overpass 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 are
actually on the ice, and avoid sudden steering
maneuvers.
If You Are 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:
Turn on your hazard ashers.
Tie a red cloth to your vehicle to alert police
that you have been stopped by the snow.
Put on extra clothing or wrap a blanket
around you. If you do not have blankets
or extra clothing, make body insulators from
newspapers, burlap bags, rags, oor
mats — anything you can wrap around
yourself or tuck under your clothing to
keep warm.
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