Anti-Lock Brake System
Warning Light
Your vehicle may have
the Anti-Lock Brake
System (ABS).
This light will come on when your engine is
started and may stay on for several seconds.
This is normal.If the light stays on, turn the ignition to off.
If the light comes on and the chime sounds when
you are driving, stop as soon as possible and
turn the ignition off. Then start the engine again
to reset the system. If the light still stays on,
or comes on again while you are driving, your
vehicle needs service. If the regular brake system
warning light is not on, you still have brakes,
but you do not have anti-lock brakes. If the regular
brake system warning light is also on, you do
not have anti-lock brakes and there is a problem
with your regular brakes. SeeBrake System
Warning Light on page 206earlier in this section.
The ABS warning light will come on brie y
when you turn the ignition key to ON. This is
normal. If the light does not come on then,
have it xed so it will be ready to warn you if
there is a problem.
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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.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modi cations on page 344.
Braking
SeeBrake System Warning Light on page 206.
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.
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.
292
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
Modi cations on page 344.
Anti-Lock Brake System (ABS)
Your vehicle might have the Anti-Lock Brake
System (ABS), an advanced electronic braking
system that will help prevent a braking skid.
If your vehicle has
ABS, this warning
light on the instrument
panel will come on
brie y when you start
your vehicle.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.
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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, the computer keeps receiving
updates on wheel speed and controls braking
pressure accordingly.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 the 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 might feel a slight brake pedal pulsation
or notice some noise, but this is normal.
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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 — might 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 293.
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
(TCS) 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
reduces engine power and may also upshift
the transmission to limit wheel spin. Also, the
traction control system activates the appropriate
corner brakes to gain even quicker control to
limit wheel spin.
295
The traction you can get in a curve depends on
the condition of the 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 295orEnhanced Traction System (ETS)
on page 297.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
the 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-dealer/non-retailer accessories can
affect your vehicle’s performance. SeeAccessories
and Modi cations on page 344.
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