brakes BUICK TERRAZA 2007 User Guide

This message continues to display for two seconds
if it has not been acknowledged when the engine
is turned off. It also re-displays for two seconds if
the message has been acknowledged, but the
condition still exists when the engine is turned off.
If the condition still exists, the message re-appears
when the engine is turned on.
LIFT GATE AJAR
This message displays when the liftgate is not
closed completely. Make sure that the liftgate is
closed completely. SeeLiftgate on page 119.
This message displays while the ignition is in RUN.
A chime sounds when the ignition is shifted out
of PARK (P). Press any of the DIC buttons
to acknowledge this message and to clear it from
the screen.
This message continues to display for two seconds
if it has not been acknowledged when the engine
is turned off. It also re-displays for two seconds if
the message has been acknowledged, but the
condition still exists when the engine is turned off.
If the condition still exists, the message re-appears
when the engine is turned on.
LOW BRAKE FLUID
This message displays when the brake uid
level is low. Have the brake system serviced by
your dealer as soon as possible. SeeBrakes
on page 434for proper uid level.
The brake system warning light also appears on
the instrument panel cluster when this message
appears on the DIC. SeeBrake System Warning
Light on page 214.
This message displays and a chime sounds only
while the ignition is in RUN. Press any of the
DIC buttons to acknowledge this message and to
clear it from the screen.
This message continues to display for two seconds
if it has not been acknowledged when the engine
is turned off. It also re-displays for two seconds if
the message has been acknowledged, but the
condition still exists when the engine is turned off.
If the condition still exists, the message re-appears
when the engine is turned on.
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Control of a Vehicle
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.
Sometimes, as when you are driving on snow or
ice, it is easy to ask more of those control systems
than the tires and road can provide. That means
you can lose control of your vehicle. SeeTraction
Control System (TCS) on page 353and
StabiliTrak
®System on page 355.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 400.
Braking
SeeBrake System Warning Light on page 214.
Braking action involves perception time and
reaction time.
First, you have to decide to push on the brake
pedal. That is perception time. Then you have to
bring up your foot and do it. That is reaction time.
Average reaction time is about three-fourths of a
second. But that is 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 three-fourths 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 is
pavement or gravel; the condition of the road,
whether it is wet, dry, or icy; tire tread; the
condition of the brakes; the weight of the vehicle;
and the amount of brake force applied.
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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. The brakes may not have
time to cool between hard stops. The 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 vehicle’s engine ever stops while you are
driving, brake normally but do not pump the
brakes. If you do, the pedal may get harder to
push down. If the 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.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 400.Anti-Lock Brake System (ABS)
Your vehicle has the Anti-Lock Brake System
(ABS), an advanced electronic braking system that
will help prevent a braking skid.
When you start your engine and begin to drive
away, ABS 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 ABS, this warning
light will stay on.
SeeAnti-Lock Brake
System Warning
Light on page 215.
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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
With ABS, you can steer and brake at the same
time. In many emergencies, steering can help you
more than even the very best braking.
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 if
it senses that one or both of the front wheels
are spinning or beginning to lose traction. When
this happens, the system brakes the spinning
wheel(s) and/or reduces engine power to
limit wheel spin.
The TRACTION CONTROL ACTIVE message will
come on in the Driver Information Center (DIC)
when the traction control system is limiting 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 re-engage the cruise control.
353

When the STABILITY CONTROL ACTIVE
message is on, you should continue to steer in the
direction you want to go. The system is designed to
help you in bad weather or other difficult driving
situations by making the most of whatever road
conditions will permit. For more information on the
stability messages, seeDriver Information Center
(DIC) on page 223.
If the StabiliTrak
®system turns off, the traction
control system warning light will illuminate, and the
STABILITY CONTROL OFF message will
appear on the DIC to warn the driver that
StabiliTrak
®is no longer available to assist you
with directional control of the vehicle. Adjust your
driving accordingly.
To realize the full benets of the stability
enhancement system, you should normally leave
StabiliTrak
®on, but it may be necessary to
turn the system off if your vehicle is stuck in sand,
mud, ice or snow, and you want to “rock” your
vehicle to attempt to free it. SeeRocking
Your Vehicle to Get It Out on page 378andIf
Your Vehicle is Stuck in Sand, Mud, Ice, or Snow
on page 377.
Traction Control Operation
The traction control system is part of the
StabiliTrak®system. Traction control limits wheel
spin by reducing engine power to the wheels
(engine speed management) and by applying
brakes.
The traction control system is enabled
automatically when you start your vehicle. It will
activate and display the TRACTION CONTROL
ACTIVE message in the DIC if it senses that one
or both of the front wheels are spinning or
beginning to lose traction while driving.
If the brake traction-control system activates
constantly or if the brakes have heated up due to
high-speed braking, brake traction-control will
be disabled and the TRACTION CONTROL
ACTIVE message will be displayed. In the limited
mode, the traction control system will only use
engine traction-control and is limited in its ability to
provide optimal performance since the system
will not utilize brake traction-control to control slip
on the drive wheels. The system will return to
normal operation after the brakes have cooled.
This can take up to two minutes or longer
depending on brake usage.
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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 are in a curve, speed is the one
factor you can control.
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 353andStabiliTrak
®System on
page 355.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 400.
358

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 350. 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.
359

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.
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.
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
362

It is wise to keep your windshield wiper and
washer system 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.
366