brake GMC SIERRA 1997 Owner's Manual

Brake System Warning Light
Your vehicle’s hydraulic brake system is divided into
two parts. If
one part isn’t working, the other part can
still work and stop you. For good braking, though,
you
need both parts working well.
If the warning light comes on, there could be a brake
problem. Have your brake system inspected right away.
This light should come on
briefly when
you turn the
ignition key to
RUN. If it
doesn’t come on then,
have it fixed so it will be
ready to warn
you if
there’s
a problem.
I
Your brake system may not be working properly
if the brake system warning light is on. Driving
with the brake system warning light
on can lead
to an accident. If the light is still on after you’ve
pulled
off the road and stopped carefully, have
the vehicle towed for service.
When the ignition is on, the brake system warning light
will also come
on when you set your parking brake. The
light will stay on
if your parking brake doesn’t release
fully. If it stays on after your parking brake is fully
released,
it means you have a brake problem.
If the light comes on while you are driving, pull off
the
road and stop carefully. You may notice that the pedal is
harder to push. Or, the pedal may go closer to the floor.
It may take longer
to stop. If the light is still on, have the
vehicle towed for service. (See “Towing Your Vehicle”
in the Index.)
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Anti-Lock Brake System Warning Light
ANTI -
LOCK
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay
on for several seconds.
That’s normal.
If the light stays on, or comes
on when you’re driving,
your vehicle needs service. If
the regular brake system
warning light isn’t on, you still have brakes, but you
don’t have anti-lock brakes. If the regular brake system
warning light is
also on, you don’t have anti-lock brakes
and there’s a problem with your regular brakes. See
“Brake System Warning Light” earlier in this section.
The anti-lock brake system warning light should come
on briefly when you
turn the ignition key to RUN. If the
light doesn’t come on then, have it fixed
so it will be
ready to warn you
if there is a problem.
Engine Coolant Temperature Gage
Ill This gage shows the engine
1
*\\I‘
00
%,
0
260
coolant temperature.
It also provides an indicator
of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210°F
(lOO°C) or less. If you are pulling a
load or going up hills, it is normal for
the temperature to
fluctuate and approach the
260°F (125°C) mark. If the
gage reaches the 260°F ( 125 “C) mark, it indicates that
the cooling system is working beyond its capacity.
In “Problems on the Road,” this manual shows what to
do. See “Engine Overheating” in the Index.
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Defensive Driving
The best advice anyone can give about driving is:
Drive defensively.
Please start with a very important safety device in your vehicle: Buckle up. (See “Safety Belts”
in the Index.)
Defensive driving really means “be ready for anything.”
On city streets, rural roads or freeways, it means
“always expect the unexpected.”
Assume that pedestrians or other drivers are going to be
careless and make mistakes. Anticipate what they might
do. Be ready for their mistakes.
Rear-end collisions are about
the most preventable
of accidents. Yet they are common. Allow enough
following distance. It’s
the best defensive driving
maneuver,
in both city and rural driving. You never
know when the vehicle in front
of you is going to brake
or turn suddenly.
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Control of a Vehicle Braking
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. Braking action involves
perception
time and
reaction time.
First, you have to decide to push on the brake pedal.
That’s
perception time. Then you have to bring up your
foot 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; the condition of your brakes; the weight of the
vehicle and the amount
of brake force applied.
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 braking. 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
between 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 (ABS)
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 and 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. This is normal.
ANTI -
LOCK
If there’s a problem with the
anti-lock brake system, this
warning light will stay on.
See “Anti-Lock Brake
System Warning Light”
in the Index.
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Here’s how anti-lock works. Let’s say the road is wet.
You’re driving safely. Suddenly an animal jumps out
in
front of you.
You slam on the brakes. Here’s 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 the
rear wheels. The anti-lock system can change the brake pressure
faster than any driver could. The computer is
programmed to make the most
of available tire and
road conditions.
You can 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: 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 suddenly slows or stops. Always leave
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 brakes
vibrate, or you may notice some noise, but this is normal.
On vehicles
with four-wheel drive, your anti-lock brakes
work at all times
-- whether you are in two-wheel drive
or four-wheel drive.
Braking in Emergencies
With anti-lock, you can steer and brake at the same
time. In many emergencies, steering can help you more
than even the very best braking.
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.
Variable Effort Steering
This system varies the amount of steering effort
proportionate
to your vehicle speed. Steering is easier
at lower speeds for maneuvering and parking ease. As
your vehicle speed increases, the steering effort also
increases.
At highway speeds, the amount of steering
effort is increased for vehicle control and stability.
Steering Tips
Driving on Curves
It’s important to take curves at a reasonable speed.
A lot of the “driver lost control” accidents mentioned on
the news happen on curves. Here’s
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’s no traction, inertia will keep
the vehicle going in the same direction.
If you’ve ever
tried to steer a vehicle on wet ice, you’ll 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’re
in a curve, speed is the one factor you can control.
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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. 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 course,
the posted speeds are
based on good weather and road conditions. Under less
favorable conditions you’ll 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.
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 vehicle 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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If other cars are lined up to pass a slow vehicle, wait
your turn. But take care that someone
isn’t 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 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
if
your right outside mirror is convex, the vehicle you
just passed may seem to be farther away from you
than
it really is.)
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.
following driver to get ahead of you. Perhaps you
can ease a little to the right.
0 Try not to pass more than one vehicle at a time
If you’re being passed, make it easy for the
Loss of Control
Let’s review what driving experts say about what
happens when
the three control systems (brakes, steering
and acceleration) don’t have enough friction where the
tires meet the road to do what the driver has asked.
In
any emergency, don’t 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
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 and an acceleration skid are best
handled by easing your foot off the accelerator pedal.
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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’ll
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 engine braking 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.
Remember: Any anti-lock brake system (ABS) helps
avoid only the braking skid.
Driving Guidelines
Off-Road Driving with Your
Four-Wheel-Drive Vehicle
This off-road guide is for vehicles that have
four-wheel drive.
Also, see “Anti-Lock Brakes” in the Index.
If your vehicle doesn’t have four-wheel drive, you
shouldn’t drive off-road unless you’re
on a level,
solid surface.
Off-road dnving can be great fun. But
it does have
some definite hazards. The greatest of these is the
terrain itself.
“Off-roading” means you’ve left the great North
American road system behind. Traffic lanes aren’t
marked. Curves aren’t banked. There are no road signs.
Surfaces can be slippery, rough, uphill
or downhill. In
short, you’ve gone right back to nature.
Off-road driving involves some new skills. And that’s
why it’s very important that you read this guide. You’ll \
find many driving tips and suggestions. These will help
make your off-road driving safer and more enjoyable.
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