traction control CHEVROLET CORVETTE 2002 5.G User Guide

4-6
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'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. Also see ªTraction Control System
(TCS)º and ªActive Handling Systemº in the Index.
Braking
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 3/4 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.

4-9
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
firmly and let anti
-lock work for you. You may hear a
motor or clicking noise and feel the brake pedal move
a little during a stop, but this is normal.
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.
Traction Control System (TCS)
Your vehicle has a traction control system called
TCS that limits wheel spin. This is especially useful in
slippery road conditions. The system operates only if it
senses that the rear wheels are spinning too much or
are beginning to lose traction. When this happens, the
system works the rear brakes and reduces engine power
(by closing the throttle and managing engine spark) to
limit wheel spin.
The TRACTION SYS ACTIVE message will
come on when the TCS system is limiting wheel spin.
See ªTraction Sys Active Messageº in the Index.
You may feel or hear the system working, but this
is normal.
If your vehicle is in cruise control when the
TCS 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. See ªCruise Controlº
in the Index.

4-12
The Active Handling System comes on automatically
whenever you start your vehicle. To help maintain
directional control of the vehicle, you should always
leave the system on. You can turn the system off if you
ever need to. If you turn the Active Handling System
off, the Traction Control System will also be turned off.
Adjust your driving accordingly.
To turn the system off, press
the ACTIVE HANDLING
button on the console. You
can turn the system on and
off at any time by pressing
the button. The DIC will
display the appropriate
message when you push
the button.
Competitive Driving Mode
The driver can select the optional handling mode by
pressing the ACTIVE HANDLING button on the
console for more than five seconds. Competitive
Driving mode allows the driver to have full control of
the rear wheels while the Active Handling System
helps steer the vehicle by selective brake application.
The instrument cluster light will not be on. The Traction
Control System will not be operating. Adjust your
driving accordingly.
When you press the ACTIVE HANDLING button
again, or turn the ignition to ACC, the Active
Handling and Traction Control Systems will be on.
The TRAC/ACT HNDLG
-ON message will be
displayed temporarily in the DIC and a chime will
be heard.

4-13
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.
Magnetic Speed Variable Assist Steering
Your vehicle is equipped with a steering system that
continuously adjusts the effort you feel when steering
at all vehicle speeds. It provides ease when parking
yet a firm, solid feel at highway speeds.
Steering Tips
Driving on Curves
It's important to take curves at a reasonable speed.
A lot of the ªdriver lost controlº 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.
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. Refer to
ªTraction Control Systemº in the Index.
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 ªdriveº 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.

4-17
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 ªoverdrivingº 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 is best handled by easing your foot
off the accelerator pedal.
Remember: Any traction control system helps avoid
only the acceleration skid.If your TCS 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 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 ªmirrored surfaceº
-- and
slow down when you have any doubt.
Remember: Any anti
-lock brake system (ABS) helps
avoid only the braking skid.

4-29 Driving on Snow or Ice
Most of the time, those places where your tires meet
the road probably have good traction.
However, if there is snow or ice between your tires
and the road, you can have a very slippery situation.
You'll have a lot less traction or ªgripº and will need
to be very careful.
What's the worst time for this? ªWet ice.º Very cold
snow or ice can be slick and hard to drive on. But wet
ice can be even more trouble because it may offer the
least traction of all. You can get wet ice when it's about
freezing (32
F; 0
C) and freezing rain begins to fall.
Try to avoid driving on wet ice until salt and sand crews
can get there.
Whatever the condition
-- smooth ice, packed, blowing
or loose snow
-- drive with caution.
Keep your traction control system on. It improves
your ability to accelerate when driving on a slippery
road. Even though your vehicle has the TCS system,
you'll want to slow down and adjust your driving to the
road conditions. If your vehicle has the optional Active
Handling System, it may also activate. See ªTraction
Control Systemº and ªActive Handling Systemº in
the Index.

5-27
If You're Stuck: In Sand, Mud,
Ice or Snow
In order to free your vehicle when it is stuck, you will
need to spin the wheels, but you don't want to spin
your wheels too fast. The method known as ªrockingº
can help you get out when you're stuck, but you must
use caution.
CAUTION:
If you let your tires spin at high speed, they can
explode, and you or others could be injured.
And, the transmission or other parts of the
vehicle can overheat. That could cause an engine
compartment fire or other damage. When you're
stuck, spin the wheels as little as possible. Don't
spin the wheels above 35 mph (55 km/h) as shown
on the speedometer.
NOTICE:
Spinning your wheels can destroy parts of your
vehicle as well as the tires. If you spin the wheels
too fast while shifting your transmission back
and forth, you can destroy your transmission.
For information about using tire chains on your vehicle,
see ªTire Chainsº in the Index.
Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will clear
the area around your front wheels. You should turn your
TCS System off. See ªTraction Control Systemº in the
Index. Then shift back and forth between REVERSE (R)
and a forward gear, spinning the wheels as little as possible.
For a manual transmission, shift slowly between either
FIRST (1) or SECOND (2) and REVERSE (R), allowing
the wheels to stop before shifting into gear. Release the
accelerator pedal while you shift, and press lightly on
the accelerator pedal when the transmission is in gear.
By slowly spinning your wheels in the forward and
reverse directions, you will cause a rocking motion that
may free your vehicle. If that doesn't get you out after a
few tries, you may need to be towed out. If you do need to
be towed out, see ªTowing Your Vehicleº in the Index.

6-48 Uniform Tire Quality Grading
Quality grades can be found where applicable on the
tire sidewall between tread shoulder and maximum
section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration, which grades tires by
treadwear, traction and temperature performance.
(This applies only to vehicles sold in the United States.)
The grades are molded on the sidewalls of most
passenger car tires. The Uniform Tire Quality Grading
system does not apply to deep tread, winter
-type snow
tires, space
-saver or temporary use spare tires, tires with
nominal rim diameters of 10 to 12 inches (25 to 30 cm),
or to some limited
-production tires.
While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course.
For example, a tire graded 150 would wear one and
a half (1 1/2) times as well on the government course
as a tire graded 100. The relative performance of
tires depends upon the actual conditions of their use,
however, and may depart significantly from the norm
due to variations in driving habits, service practices
and differences in road characteristics and climate.
Traction
-- AA, A, B, C
The traction grades, from highest to lowest, are AA,
A, B, and C. Those grades represent the tire's ability to
stop on wet pavement as measured under controlled
conditions on specified government test surfaces of
asphalt and concrete. A tire marked C may have poor
traction performance. Warning: The traction grade
assigned to this tire is based on straight
-ahead
braking traction tests, and does not include acceleration,
cornering, hydroplaning, or peak traction characteristics.

6-53 Tire Chains
CAUTION:
Don't use tire chains. There's not enough clearance.
Tire chains used on a vehicle without the proper
amount of clearance can cause damage to the
brakes, suspension or other vehicle parts. The area
damaged by the tire chains could cause you to lose
control of your vehicle and you or others may be
injured in a crash.
Use another type of traction device only if its
manufacturer recommends it for use on your
vehicle and tire size combination and road
conditions. Follow that manufacturer's
instructions. To help avoid damage to your
vehicle, drive slowly, readjust or remove the
device if it's contacting your vehicle, and don't
spin your wheels.
If you do find traction devices that will fit,
install them on the rear tires.
Lifting Your Corvette
CAUTION:
Lifting a vehicle can cause an injury. The vehicle
can slip off the jack and roll over you or other
people. You and they could be badly injured.
Find a level place to lift your vehicle. To help
prevent the vehicle from moving:
1. Set the parking brake firmly.
2. Put an automatic transmission shift lever in
PARK (P), or shift a manual transmission to
FIRST (1) or REVERSE (R).
3. Turn off the engine.
To be even more certain the vehicle won't
move, you can put blocks in front of and
behind the wheels.