2001 GMC ENVOY lock

3-43
Unlocking the Theft-Deterrent Feature After a
Power Loss
Enter your secret code as follows; pause no more than
15 seconds between steps:
1. Turn the ignition on. LOC will appear on the display.
2. Press MN and 000 will appear on the display.
3. Press MN again to make the last two digits agree
with your code.
4. Press HR to make the first one or two digits agree
with your code.
5. Press AM
-FM after you have confirmed that the
code matches the secret code you have written down.
The display will show SEC, indicating the radio is
now operable and secure.
If you enter the wrong code eight times, INOP will
appear on the display. You will have to wait an hour with
the ignition on before you can try again. When you try
again, you will only have three chances to enter the
correct code before INOP appears.
If you lose or forget your code, contact your dealer.Disabling the Theft
-Deterrent Feature
Enter your secret code as follows; pause no more than
15 seconds between steps:
1. Turn the ignition to ACCESSORY or RUN.
2. Turn the radio off.
3. Press the ª1º and ª4º buttons together. Hold them
down until SEC shows on the display.
4. Press MN and 000 will appear on the display.
5. Press MN again to make the last two digits agree
with your code.
6. Press HR to make the first one or two digits agree
with your code.
7. Press AM FM after you have confirmed that the code
matches the secret code you have written down. The
display will show
---, indicating that the radio
is no longer secured.
If the code entered is incorrect, SEC will appear on the
display. The radio will remain secured until the correct
code is entered.
When battery power is removed and later applied to a
secured radio, the radio won't turn on and LOC will
appear on the display.
To unlock a secured radio, see ªUnlocking the
Theft
-Deterrent Feature After a Power Lossº earlier
in this section.
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4-8
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.
If there's a problem with
the anti
-lock brake system,
this warning light will stay
on. See ªAnti
-Lock Brake
System Warning Lightº in
the Index.
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4-9
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 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.
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4-10
As you brake, your computer keeps receiving updates on
wheel speed and controls braking pressure accordingly.
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 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.
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 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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4-12
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.
Off-Road Recovery
You may find that your right wheels have dropped off the
edge of a road onto the shoulder while you're driving.
If the level of the shoulder is only slightly below the
pavement, recovery should be fairly easy. Ease off the
accelerator and then, if there is nothing in the way, steer
so that your vehicle straddles the edge of the pavement.
You can turn the steering wheel up to one
-quarter turn
until the right front tire contacts the pavement edge.
Then turn your steering wheel to go straight down
the roadway.
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4-15
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.
Off-Road Driving with Your
Four
-Wheel-Drive Vehicle
This off-road guide is for vehicles that have
four
-wheel drive.
Also, see ªAnti
-Lock Brakesº 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 driving can be great fun. But it does have
some definite hazards. The greatest of these is the
terrain itself.
ªOff
-roadingº 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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4-17 Environmental Concerns
Off-road driving can provide wholesome and satisfying
recreation. However, it also raises environmental
concerns. GM recognizes these concerns and urges
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
-- shrubs, flowers, trees, grasses -- or
disturb wildlife (this includes wheel
-spinning,
breaking down trees or unnecessary driving through
streams or over soft ground).

Always carry a litter bag . . . make sure all refuse is
removed from any campsite before leaving.

Take extreme care with open fires (where permitted),
camp stoves and lanterns.

Never park your vehicle over dry grass or other
combustible materials that could catch fire 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
driving 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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4-20
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 find 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 firm 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 find
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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