2003 GMC ENVOY lock

Let's say the road is wet and you're driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. 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 both 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. This can help you 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
®rmly and let anti-lock work for you. You may feel
the brakes vibrate, or you may notice some noise, 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 Assist System (TAS)
Your two-wheel drive vehicle may have a Traction
Assist System (TAS) 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 reduces engine
power to limit wheel spin.
The low traction symbol next to the button will come on
when the TAS is limiting wheel spin. You may feel or
hear the system working, but this is normal.
The Traction Assist System may operate on dry roads
under some conditions. When this happens, you
may notice a reduction in acceleration. This is normal
and doesn't mean there's a problem with your vehicle.
Examples of these conditions include a hard
acceleration in a turn, an abrupt upshift or downshift of
the transmission or driving on rough roads.
If your vehicle is in cruise control when the TAS 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 under
Turn Signal/Multifunction
Lever on page 3-7. When the traction control off symbol
on the button is on, the TAS is off and will not limit
wheel spin. Adjust your driving accordingly.
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The traction control off symbol on the button will come
on under the following conditions:
·The Traction Assist System is turned off, either by
pressing the TAS on/off button or by turning off
the automatic engagement feature of the TAS.
·The transmission is in FIRST (1) gear; TAS will not
operate in this gear. This is normal.
·The vehicle is driven on an extremely rough road.
When the vehicle leaves the rough surface, slows
down or stops, the light will go off and TAS will
be on again. This is normal.
·A Traction Assist System, Anti-Lock Brake System
or engine-related problem has been detected and
the vehicle needs service.
The Traction Assist System, as delivered from the
factory, will automatically come 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 TAS off if you ever need
to. You should turn the TAS off if your vehicle ever
gets stuck in sand, mud or snow and rocking the vehicle
is required.To turn the system on or off, press the TAS button
located near the shift lever. If you used the button to turn
the system off, the traction control off symbol on the
button will come on and stay on.
You can turn the system back on at any time by
pressing the button again. The traction control off symbol
on the button should go off.
If desired, you can change the TAS automatic
engagement feature so that the system will not come on
automatically when the engine is started. To do so:
1. Turn the ignition to RUN.
2. Move the shift lever to NEUTRAL.
3. Apply the brake pedal and press the accelerator
pedal to the ¯oor.
4. Press and hold the TAS button for at least six
seconds.
5. Release the TAS button and both pedals.
6. Start the engine and wait a few seconds.
The next time you start your vehicle, the TAS will not
automatically come on. You can restore the automatic
feature by using the same procedure. Whether the TAS
is set to come on automatically or not, you can always
turn the system on or off by pressing the TAS button.
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Locking Rear Axle
If your vehicle has this feature, your locking rear axle
can give you additional traction on snow, mud, ice, sand
or gravel. It works like a standard axle most of the
time, but when one of the rear wheels has no traction
and the other does, this feature will allow the wheel with
traction to move the vehicle.
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.
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 whenyou 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 Ð steering and acceleration Ð 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. See
Traction Assist
System (TAS) on page 4-8.
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.
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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 ®nd
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 Ð if you can stop
in time. But sometimes you can't; there isn't room.
That's the time for evasive action Ð steering around the
problem.
Your vehicle can perform very well in emergencies like
these. First apply your brakes.
See
Braking on page 4-5. 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.An emergency like this requires close attention and a
quick decision. If you are holding the steering wheel at
the recommended 9 and 3 o'clock positions, you
can turn it a full 180 degrees very quickly without
removing either hand. But you have to act fast, steer
quickly, and just as quickly straighten the wheel
once you have avoided the object.
The fact that such emergency situations are always
possible is a good reason to practice defensive driving
at all times and wear safety belts properly.
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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 have the Traction Assist System, remember: It
helps avoid only the acceleration skid. If you do not have
this 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.
Remember: Any anti-lock brake system (ABS) helps
avoid only the braking skid.
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Environmental Concerns
Off-road driving can provide wholesome and satisfying
recreation. However, it also raises environmental
concerns. We recognize these concerns and urge every
off-roader to follow these basic rules for protecting
the environment:
·Always use established trails, roads and areas that
have been specially set aside for public off-road
recreational driving; obey all posted regulations.
·Avoid any driving practice that could damage
the environment Ð shrubs, ¯owers, trees,
grasses Ð or disturb wildlife (this includes
wheel-spinning, breaking down trees or
unnecessary driving through streams or over soft
ground).
·Always carry a litter bag Ð make sure all refuse is
removed from any campsite before leaving.
·Take extreme care with open ®res (where
permitted), camp stoves and lanterns.
·Never park your vehicle over dry grass or other
combustible materials that could catch ®re from
the heat of the vehicle's exhaust system.
Traveling to Remote Areas
It makes sense to plan your trip, especially when going
to a remote area. Know the terrain and plan your
route. You are much less likely to get bad surprises.
Get accurate maps of trails and terrain. Try to learn of
any blocked or closed roads.
It's also a good idea to travel with at least one other
vehicle. If something happens to one of them, the other
can help quickly.
Does your vehicle have a winch? If so, be sure to read
the winch instructions. In a remote area, a winch
can be handy if you get stuck. But you'll want to know
how to use it properly.
Getting Familiar with Off-Road Driving
It's a good idea to practice in an area that's safe
and close to home before you go into the wilderness.
Off-road driving does require some new and different
skills. Here's what we mean.
Tune your senses to different kinds of signals. Your
eyes, for example, need to constantly sweep the terrain
for unexpected obstacles. Your ears need to listen
for unusual tire or engine sounds. With your arms,
hands, feet and body, you'll need to respond to
vibrations and vehicle bounce.
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Approaching a Hill
When you approach a hill, you need to decide if it's one
of those hills that's just too steep to climb, descend
or cross. Steepness can be hard to judge. On a very
small hill, for example, there may be a smooth, constant
incline with only a small change in elevation where
you can easily see all the way to the top. On a large hill,
the incline may get steeper as you near the top, but
you may not see this because the crest of the hill
is hidden by bushes, grass or shrubs.
Here are some other things to consider as you approach
a hill.
·Is there a constant incline, or does the hill get
sharply steeper in places?
·Is there good traction on the hillside, or will the
surface cause tire slipping?
·Is there a straight path up or down the hill so you
won't have to make turning maneuvers?
·Are there obstructions on the hill that can block
your path (boulders, trees, logs or ruts)?
·What's beyond the hill? Is there a cliff, an
embankment, a drop-off, a fence? Get out and walk
the hill if you don't know. It's the smart way to
®nd out.
·Is the hill simply too rough? Steep hills often have
ruts, gullies, troughs and exposed rocks because
they are more susceptible to the effects of erosion.
Driving Uphill
Once you decide you can safely drive up the hill, you
need to take some special steps.
·Use a low gear and get a ®rm grip on the steering
wheel.
·Get a smooth start up the hill and try to maintain
your speed. Don't use more power than you
need, because you don't want your wheels to start
spinning or sliding.
·Try to drive straight up the hill if at all possible. If
the path twists and turns, you might want to ®nd
another route.
{CAUTION:
Turning or driving across steep hills can be
dangerous. You could lose traction, slide
sideways, and possibly roll over. You could be
seriously injured or killed. When driving up
hills, always try to go straight up.
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