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
front wheel and at both rear wheels.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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If your vehicle has the vehicle stability control
system, it includes a brake assist system which
provides more powerful braking during a sudden,
hard brake application. See “Vehicle Stability
Control System” underTraction Control System
(TCS) on page 230.
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 227.
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.
You may feel or hear the system working, but this
is normal. Leave the system on during ordinary
driving so that it can operate when needed. When
the ignition is turned to ON, the system
automatically turns on.
This light should come
on brie y when you
start the engine.
If it stays on or comes on while you are driving,
there is a problem with your traction control
system.The TRAC OFF button
is located to the left of
the steering wheel
below the instrument
panel cluster.
When getting the vehicle out of mud or newly
fallen snow, turn off the traction control system.
The system that controls engine performance
interferes with the process of freeing the
front wheels. To turn off traction control, press the
TRAC OFF button. The traction control system
warning light will come on. The vehicle stability
control system (StabiliTrak
®) is always activated,
even when the traction control system is turned
off. To turn the traction control system back
on, press the TRAC OFF button again. The
traction control system warning light will go off.
SeeTraction Control System (TCS) Warning Light
on page 168for more information.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modi cations on page 272for more information.
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StabiliTrak®System
Your vehicle may have this feature. The
StabiliTrak®system helps provide integrated
control of the systems such as anti-lock brake
system, traction control and engine control.
This system automatically controls the brakes and
engine to help prevent the vehicle from skidding
when cornering on a slippery road surface or
turning the steering wheel abruptly.
This system will activate when your vehicle speed
reaches or exceeds 9 mph (15 km/h), and will
deactivate when the vehicle speed reduces
to below 9 mph (15 km/h).
You may hear a sound in the engine compartment
for a few seconds when the engine is started or
just after the vehicle begins to move. This
means that the system is in the self-check mode,
but does not indicate a malfunction.
If the vehicle is going to skid during driving, the
traction control system warning light will blink and
an alarm will sound intermittently. Adjust your
driving accordingly.This light warns that
there is a problem
somewhere in
the traction control
system or StabiliTrak®.
Panic Brake Assist
Your vehicle has a panic brake assist system that
monitors the intention of the driver while braking.
If the system senses that the driver has applied
hard/fast pressure to the brake pedal, the system
will generate additional pressure, making it
easier for the driver to maintain brake application.
When this happens the brake pedal will feel
easier to push. Just hold the brake pedal down
rmly and let the system work for you. You
may feel the brakes vibrate, or you may notice
some noise but this is normal. The brakes
will return to normal operation after the brake
pedal has been released.
The brake assist system becomes operational
after the vehicle has accelerated to a speed
in excess of approximately 6 mph (10 km/h). It
stops operating when the vehicle decelerates to a
speed below approximately 3 mph (5 km/h).
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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.
Steering Tips
It is important to take curves at a reasonable
speed.
A lot of the “driver lost control” accidents
mentioned on the news happen on curves.
Here is 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 is
no traction, inertia will keep the vehicle going in the
same direction. If you have ever tried to steer a
vehicle on wet ice, you will 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 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.
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.
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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
Modi cations on page 272.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 — but, unless
you have anti-lock brakes, not enough to lock
your wheels.
SeeBraking on page 226. 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 that your 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.
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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 and an acceleration skid are 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 will 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 reducing vehicle speed 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.
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