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 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 the
anti
-lock pump or motor operate, and feel the brake
pedal pulsate, 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
Your vehicle 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 rear wheels are spinning or beginning to
lose traction. When this happens, the system brakes the
spinning wheel(s) and/or reduces engine power to limit
wheel spin.You may feel or hear the system working, but this
is normal.
This warning light will
come on to let you know if
there's a problem with your
traction control system.
See ªTraction Control System Warning Lightº in the
Index. When this warning light is on, the system will not
limit wheel spin. Adjust your driving accordingly.
When the system is limiting wheel spin, the Traction
Control System warning light will be blinking.
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 Vehicleº in the Index.
4-10
To turn the system off, press
the TC (traction control)
button located in the
glove box.
If you press the TC button once, the traction control
system will turn off and the traction control system
warning light will come on. Press the TC button again
to turn the system back on. If you press and hold the
TC button for five seconds, the Stabilitrak system will
turn off. Press the TC button again to turn Stabilitrak
back on.
Stabilitrak - Vehicle Stability
Enhancement System (If Equipped)
Your vehicle may be equipped with a vehicle stability
enhancement system called Stabilitrak. Stabilitrak is an
advanced computer controlled system that assists you
with directional control of the vehicle in difficult driving
conditions.Stabilitrak has sensors that detect the direction your
vehicle is going and compares it to the direction that you
are steering the vehicle. Stabilitrak activates when the
computer senses a discrepancy between your intended
path and the direction the vehicle is actually traveling.
To assist you in returning your vehicle to the intended
path, Stabilitrak selectively applies braking pressure at
any one of the vehicle's brakes to help steer the vehicle
in the direction which you are steering.
When the system activates, a STABILITY SYS
ENGAGED message will be displayed on the Driver
Information Center. See ªDriver Information Center
Messagesº in the Index. You may also hear a noise or feel
vibration in the brake pedal. This is normal. Continue to
steer the vehicle in the direction you want it to go.
If there is a problem detected with Stabilitrak, a
SERVICE STABILITY SYS message will be displayed
on the Driver Information Center. See ªDriver
Information Center Messagesº in the Index. When this
message is displayed, the system is not operational.
Driving should be adjusted accordingly.
Stability comes on automatically whenever you start
your vehicle. To help assist you with directional control
of the vehicle, you should always leave the system on.
You can turn Stabilitrak OFF if you ever need to trough
the Traction On/Off button. See ªTraction Control
Systemº in the Index.
4-11
If your vehicle is in cruise control when the Stabilitrak
activates, the cruise control will automatically
disengage. When road conditions allow you to safely
use it again, you may reengage the cruise control. See
ªCruise Controlº in the Index.
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.
Speed Variable Assist Steering
(If Equipped)
This system varies the amount of effort required to steer
the vehicle in relation to the speed of the vehicle.
The amount of steering effort required is less at slower
speeds to make the vehicle more maneuverable and
easier to park. At faster speeds, the steering effort
increases to provide a sport
-like feel to the steering.
This provides maximum control and stability.If your vehicle seems harder to steer than normal when
parking or driving slowly, there may be a problem with
the system. You will still have power steering, but
steering will be stiffer than normal at slow speeds. See
your dealer for service.
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.
4-12
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.
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 ªBraking in
Emergenciesº 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.
4-15
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
your right 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.
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.
If you're being passed, make it easy for the
following driver to get ahead of you. Perhaps you
can ease a little to the right.
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.
4-16
If your traction control 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.
Driving at Night
Night driving is more dangerous than day driving.
One reason is that some drivers are likely to be
impaired
-- by alcohol or drugs, with night vision
problems, or by fatigue.
4-27 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 (32F; 0C) 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 a traction control system,
you'll want to slow down and adjust your driving to the
road conditions. See ªTraction Control Systemº in
the Index.