2004 GMC ENVOY XL stop start

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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Do not get too close to the vehicle you want to
pass while you are awaiting an opportunity. For one
thing, following too closely reduces your area of
vision, especially if you are following a larger
vehicle. Also, you will not have adequate space if
the vehicle ahead suddenly slows or stops.
Keep back a reasonable distance.
When it looks like a chance to pass is coming up,
start to accelerate but stay in the right lane and do
not get too close. Time your move so you will be
increasing speed as the time comes to move into the
other lane. If the way is clear to pass, you will have a
“running start” that more than makes up for the
distance you would lose by dropping back. And if
something happens to cause you to cancel your
pass, you need only slow down and drop back again
and wait for another opportunity.
If other vehicles are lined up to pass a slow vehicle,
wait your turn. But take care that someone is not
trying to pass you as you pull out to pass the slow
vehicle. Remember to glance over your shoulder
and check the blind spot.
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.
Do not overtake a slowly moving vehicle too rapidly.
Even though the brake lamps are not ashing, it may
be slowing down or starting to turn.
If you are 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 us review what driving experts say about what
happens when the three control systems (brakes,
steering and acceleration) do not have enough friction
where the tires meet the road to do what the driver
has asked.
In any emergency, do not give up. Keep trying to steer
and constantly seek an escape route or area of less
danger.
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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 “overdriving”
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
are not 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 will 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 “mirrored surface” — 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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Scanning the Terrain
Off-road driving can take you over many different kinds
of terrain. You need to be familiar with the terrain
and its many different features. Here are some things
to consider.
Surface Conditions:Off-roading can take you over
hard-packed dirt, gravel, rocks, grass, sand, mud, snow
or ice. Each of these surfaces affects the steering,
acceleration and braking of your vehicle in different
ways. Depending upon the kind of surface you are on,
you may experience slipping, sliding, wheel spinning,
delayed acceleration, poor traction and longer braking
distances.
Surface Obstacles:Unseen or hidden obstacles can
be hazardous. A rock, log, hole, rut or bump can startle
you if you are not prepared for them. Often these
obstacles are hidden by grass, bushes, snow or even
the rise and fall of the terrain itself. Here are some
things to consider:
Is the path ahead clear?
Will the surface texture change abruptly up ahead?
Does the travel take you uphill or downhill?
(There is more discussion of these subjects later.)
Will you have to stop suddenly or change direction
quickly?When you drive over obstacles or rough terrain,
keep a rm grip on the steering wheel. Ruts, troughs
or other surface features can jerk the wheel out of your
hands if you are not prepared.
When you drive over bumps, rocks, or other obstacles,
your wheels can leave the ground. If this happens,
even with one or two wheels, you can not control the
vehicle as well or at all.
Because you will be on an unpaved surface, it is
especially important to avoid sudden acceleration,
sudden turns or sudden braking.
In a way, off-road driving requires a different kind of
alertness from driving on paved roads and highways.
There are no road signs, posted speed limits or
signal lights. You have to use your own good judgment
about what is safe and what is not.
Drinking and driving can be very dangerous on any
road. And this is certainly true for off-road driving.
At the very time you need special alertness and driving
skills, your reexes, perceptions and judgment can
be affected by even a small amount of alcohol.
You could have a serious — or even fatal — accident
if you drink and drive or ride with a driver who has been
drinking. SeeDrunken Driving on page 4-2.
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Q:What should I do if my vehicle stalls,
or is about to stall, and I can not make
it up the hill?
A:If this happens, there are some things you should
do, and there are some things you must not do.
First, here is what youshoulddo:
Push the brake pedal to stop the vehicle and keep
it from rolling backwards. Also, apply the parking
brake.
If your engine is still running, shift the transmission
to REVERSE (R), release the parking brake, and
slowly back down the hill in REVERSE (R).
If your engine has stopped running, you will need
to restart it. With the brake pedal pressed and the
parking brake still applied, shift the transmission
to PARK (P) and restart the engine. Then, shift to
REVERSE (R), release the parking brake, and
slowly back down the hill as straight as possible
in REVERSE (R).
As you are backing down the hill, put your left hand
on the steering wheel at the 12 o’clock position.
This way, you will be able to tell if your wheels are
straight and maneuver as you back down. It is
best that you back down the hill with your wheels
straight rather than in the left or right direction.
Turning the wheel too far to the left or right
will increase the possibility of a rollover.
Here are some things youmust notdo if you stall,
or are about to stall, when going up a hill.
Never attempt to prevent a stall by shifting into
NEUTRAL (N) to “rev-up” the engine and regain
forward momentum. This will not work. Your vehicle
will roll backwards very quickly and you could go
out of control.
Instead, apply the regular brake to stop the
vehicle. Then apply the parking brake. Shift to
REVERSE (R), release the parking brake,
and slowly back straight down.
Never attempt to turn around if you are about
to stall when going up a hill. If the hill is steep
enough to stall your vehicle, it is steep enough to
cause you to roll over if you turn around. If you
can not make it up the hill, you must back straight
down the hill.
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{CAUTION:
Heavy braking when going down a hill can
cause your brakes to overheat and fade.
This could cause loss of control and a serious
accident. Apply the brakes lightly when
descending a hill and use a low gear to keep
vehicle speed under control.
Q:Are there some things I should not do when
driving down a hill?
A:Yes! These are important because if you ignore
them you could lose control and have a serious
accident.
When driving downhill, avoid turns that take you
across the incline of the hill. A hill that is not too
steep to drive down may be too steep to drive
across. You could roll over if you do not drive
straight down.
Never go downhill with the transmission in
NEUTRAL (N). This is called “free-wheeling.”
Your brakes will have to do all the work and could
overheat and fade.
Q:Am I likely to stall when going downhill?
A:It is much more likely to happen going uphill. But if
it happens going downhill, here is what to do.
Stop your vehicle by applying the regular brakes.
Apply the parking brake.
Shift to PARK (P) and, while still braking, restart
the engine.
Shift back to a low gear, release the parking brake,
and drive straight down.
If the engine will not start, get out and get help.
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Stalling on an Incline
If your vehicle stalls when you are crossing an incline,
be sure you (and your passengers) get out on the
uphill side, even if the door there is harder to open.
If you get out on the downhill side and the vehicle
starts to roll over, you will be right in its path.
If you have to walk down the slope, stay out of the
path the vehicle will take if it does roll over.{CAUTION:
Getting out on the downhill (low) side of a
vehicle stopped across an incline is dangerous.
If the vehicle rolls over, you could be crushed
or killed. Always get out on the uphill (high)
side of the vehicle and stay well clear of the
rollover path.
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If the water is not too deep, drive slowly through it.
At faster speeds, water splashes on your ignition
system and your vehicle can stall. Stalling can also
occur if you get your tailpipe under water. And, as long
as your tailpipe is under water, you will never be
able to start your engine. When you go through water,
remember that when your brakes get wet, it may
take you longer to stop.
{CAUTION:
Driving through rushing water can be
dangerous. Deep water can sweep your vehicle
downstream and you and your passengers
could drown. If it is only shallow water, it can
still wash away the ground from under your
tires, and you could lose traction and roll the
vehicle over. Do not drive through rushing
water.
SeeDriving in Rain and on Wet Roads on page 4-31for
more information on driving through water.
After Off-Road Driving
Remove any brush or debris that has collected on the
underbody, chassis or under the hood. These
accumulations can be a re hazard.
After operation in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and uneven braking. Check the body structure,
steering, suspension, wheels, tires and exhaust
system for damage. Also, check the fuel lines and
cooling system for any leakage.
Your vehicle will require more frequent service due to
off-road use. Refer to the Maintenance Schedule
for additional information.
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