2004 PONTIAC GRAND PRIX traction control

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
Traction Control System (TCS)
on page 4-10andEnhanced Traction System (ETS) on
page 4-11.
Braking
Braking action involvesperception timeandreaction time.
First, you have to decide to push on the brake pedal.
That'sperception time.Then you have to bring up your
foot and do it. That'sreaction time.
Averagereaction timeis 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.
4-6

Traction Control System (TCS)
If your vehicle has the 3800 supercharged V6 engine
it has 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.
This symbol will appear on
the DIC screen when the
system is active, along with
the TRACTION CONTROL
ACTIVE message.
You may feel or hear the system working, but this is
normal.
When the traction control
system is not working, this
symbol will appear on the
instrument panel cluster.This symbol, along with
the message TRACTION
CONTROL OFF will
also display in the DIC
for three seconds when
the traction control system
is not active.
When these symbols and messages appear on the
instrument panel and the Driver's Information Center
(DIC), the system will not limit wheel spin. Adjust your
driving accordingly.
The traction control system automatically comes on
whenever you start your vehicle. To limit wheel spin,
especially in slippery road conditions, you should always
leave the system on. But you can turn the traction
control system off if you ever need to. You should turn
the system off if your vehicle ever gets stuck in
sand, mud or snow and rocking the vehicle is required.
See ªRocking Your Vehicle to Get It Outº under
If You Are Stuck: In Sand, Mud, Ice or Snow on
page 4-32.
4-10

To turn the system off,
press the traction control
button located on the
console.
If the system is limiting wheel spin when you press the
button the system will turn off instantly. You can
turn the system back on at any time by pressing the
button again.
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
reengage the cruise control. See
Cruise Control Lever
on page 3-8.
Enhanced Traction System (ETS)
If your vehicle has the 3800 V6 engine and anti-lock
brakes, your vehicle may have an Enhanced Traction
System (ETS) 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 transaxle to limit wheel spin.
This symbol will appear on
the Driver Information
Center (DIC) when your
Enhanced Traction System
is limiting wheel spin.
If your vehicle is in cruise control when the enhanced
traction 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
Cruise Control Lever
on page 3-8.
4-11

The Enhanced Traction System operates in all transaxle
shift lever positions. But the system can upshift the
transaxle only as high as the shift lever position you've
chosen, so you should use the lower gears only when
necessary. See
Automatic Transaxle Operation on
page 2-22.
This warning light appears
on the instrument panel to
indicate that the ETS is
not on.
This symbol, along with
the message TRACTION
CONTROL OFF will
also display on the DIC for
three seconds when the
ETS is not active.
See
Enhanced Traction System Warning Light on
page 3-38. When this warning light is on, the system will
not limit wheel spin. Adjust your driving accordingly.To limit wheel spin, especially in slippery road conditions,
you should always leave the ETS on. But you can turn
the system off if you ever need to. You should turn the
system off if your vehicle ever gets stuck in sand, mud or
snow and rocking the vehicle is required. See ªRocking
Your Vehicle To Get It Outº under
If You Are Stuck:
In Sand, Mud, Ice or Snow on page 4-32.
To turn the system off,
press the traction control
button located on the
console.
If the system is limiting wheel spin when you press the
button the system will turn off instantly. You can
turn the system back on at any time by pressing the
button again.
4-12

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
If your vehicle has this steering system, the system
provides less steering effort for parking and when driving
at speeds below 20 mph (32 km/h). Steering effort will
increase at higher speeds for improved road feel.
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 apply the brakes. Both control
systems Ð steering and braking Ð 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're steering through a
sharp curve and you suddenly accelerate. Those two
control systems Ð steering and acceleration Ð can
overwhelm those places where the tires meet the road
and make you lose control. See
Traction Control System
(TCS) on page 4-10orEnhanced Traction System (ETS)
on page 4-11.
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'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.
4-14

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.
If you do not have the Enhanced Traction System or the
Traction Control System, or if the 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 Ð such as enough water, ice or packed snow on
the road to make a ªmirrored surfaceº Ð and slow down
when you have any doubt.
If you have the anti-lock braking system, remember:
It helps avoid only the braking skid. If you do not have
anti-lock, then in a braking skid (where the wheels
are no longer rolling), release enough pressure on the
brakes to get the wheels rolling again. This restores
steering control. Push the brake pedal down steadily
when you have to stop suddenly. As long as the wheels
are rolling, you will have steering control.
4-18

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 (32ÉF; 0ÉC) 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.
If you have traction control or enhanced traction, keep
the system on. It will improve your ability to accelerate
when driving on a slippery road. Even though your
vehicle has a traction control system you'll want to slow
down and adjust your driving to the road conditions.
See
Traction Control System (TCS) on page 4-10.
If you don't have a traction control or enhanced traction
system, accelerate gently. Try not to break the fragile
traction. If you accelerate too fast, the drive wheels will
spin and polish the surface under the tires even more.
Unless you have the anti-lock braking system, you'll
want to brake very gently, too. (If you do have anti-lock,
see
Braking on page 4-6. This system improves your
vehicle's stability when you make a hard stop on a
slippery road.) Whether you have the anti-lock braking
system or not, you'll want to begin stopping sooner than
you would on dry pavement. Without anti-lock brakes,
4-29

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 transaxle
back and forth, you can destroy your transaxle.
See ªRocking Your Vehicle To Get It Out.º
For information about using tire chains on your vehicle,
see
Tire Chains on page 5-77.
Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear the area around your front wheels. If your vehicle
has traction control, you should turn the system off.
See
Traction Control System (TCS) on page 4-10.
Then shift back and forth between REVERSE (R) and a
forward gear, spinning the wheels as little as possible.
Release the accelerator pedal while you shift, and press
lightly on the accelerator pedal when the transaxle 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 following.
Towing
Towing Your Vehicle
Consult your dealer or a professional towing service
if you need to have your disabled vehicle towed.
See
Roadside Assistance Program on page 7-6.
If you want to tow your vehicle behind another vehicle
for recreational purposes (such as behind a motorhome),
see ªRecreational Vehicle Towingº following.
Recreational Vehicle Towing
Recreational vehicle towing means towing your vehicle
behind another vehicle ± such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as ªdinghy towingº (towing your vehicle
with all four wheels on the ground) and ªdolly towingº
(towing your vehicle with two wheels on the ground and
two wheels up on a device known as a ªdollyº).
With the proper preparation and equipment, many
vehicles can be towed in these ways. See ªDinghy
Towingº and ªDolly Towing,º following.
4-33