2005 GMC ENVOY light

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.
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 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. SeeRocking Your Vehicle to Get It Out
on page 4-44andIf You Are Stuck: In Sand, Mud, Ice
or Snow on page 4-43for more information.
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.
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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 nd that your right wheels have dropped off the
edge of a road onto the shoulder while you are 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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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 cannot 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.Driving on Off-Road Hills
Off-road driving often takes you up, down or across a
hill. Driving safely on hills requires good judgment
and an understanding of what your vehicle can and
cannot do. There are some hills that simply cannot be
driven, no matter how well built the vehicle.
{CAUTION:
Many hills are simply too steep for any vehicle.
If you drive up them, you will stall. If you drive
down them, you cannot control your speed. If
you drive across them, you will roll over. You
could be seriously injured or killed. If you have
any doubt about the steepness, do not drive
the hill.
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Are there hidden surface obstacles? Ruts? Logs?
Boulders?
What is at the bottom of the hill? Is there
a hidden creek bank or even a river bottom
with large rocks?
If you decide you can go down a hill safely, then try to
keep your vehicle headed straight down, and use a
low gear. This way, engine drag can help your brakes
and they will not have to do all the work. Descend
slowly, keeping your vehicle under control at all times.
{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.
1. Stop your vehicle by applying the regular brakes.
Apply the parking brake.
2. Shift to PARK (P) and, while still braking, restart
the engine.
3. Shift back to a low gear, release the parking brake,
and drive straight down.
4. If the engine will not start, get out and get help.
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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.Here are some tips on night driving.
Drive defensively.
Do not drink and drive.
Since you cannot see as well, you may need to
slow down and keep more space between you
and other vehicles.
Slow down, especially on higher speed roads. Your
headlamps can light up only so much road ahead.
In remote areas, watch for animals.
If you are tired, pull off the road in a safe place
and rest.
No one can see as well at night as in the daytime. But
as we get older these differences increase. A
50-year-old driver may require at least twice as much
light to see the same thing at night as a 20-year-old.
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What you do in the daytime can also affect your night
vision. For example, if you spend the day in bright
sunshine you are wise to wear sunglasses. Your eyes
will have less trouble adjusting to night. But if you
are driving, do not wear sunglasses at night. They may
cut down on glare from headlamps, but they also
make a lot of things invisible.
You can be temporarily blinded by approaching
headlamps. It can take a second or two, or even several
seconds, for your eyes to re-adjust to the dark. When
you are faced with severe glare, as from a driver
who does not lower the high beams, or a vehicle with
misaimed headlamps, slow down a little. Avoid
staring directly into the approaching headlamps.
Keep your windshield and all the glass on your vehicle
clean — inside and out. Glare at night is made much
worse by dirt on the glass. Even the inside of the glass
can build up a lm caused by dust. Dirty glass makes
lights dazzle and ash more than clean glass would,
making the pupils of your eyes contract repeatedly.
Remember that your headlamps light up far less of a
roadway when you are in a turn or curve. Keep
your eyes moving; that way, it is easier to pick out dimly
lighted objects. Just as your headlamps should be
checked regularly for proper aim, so should your eyes
be examined regularly. Some drivers suffer from
night blindness — the inability to see in dim light — and
are not even aware of it.Driving in Rain and on Wet Roads
Rain and wet roads can mean driving trouble. On a wet
road, you cannot stop, accelerate, or turn as well
because your tire-to-road traction is not as good as on
dry roads. And, if your tires do not have much tread
left, you will get even less traction. It is always wise to
go slower and be cautious if rain starts to fall while
you are driving. The surface may get wet suddenly when
your reexes are tuned for driving on dry pavement.
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The heavier the rain, the harder it is to see. Even if your
windshield wiper blades are in good shape, a heavy
rain can make it harder to see road signs and
traffic signals, pavement markings, the edge of the road,
and even people walking.
It is wise to keep your wiping equipment in good shape
and keep your windshield washer tank lled with
washer uid. Replace your windshield wiper inserts
when they show signs of streaking or missing areas on
the windshield, or when strips of rubber start to
separate from the inserts.
Driving too fast through large water puddles or even
going through some car washes can cause problems,
too. The water may affect your brakes. Try to avoid
puddles. But if you cannot, try to slow down before
you hit them.
{CAUTION:
Wet brakes can cause accidents. They will not
work as well in a quick stop and may cause
pulling to one side. You could lose control of
the vehicle.
After driving through a large puddle of water
or a car wash, apply your brake pedal lightly
until your brakes work normally.
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Hydroplaning
Hydroplaning is dangerous. So much water can build up
under your tires that they can actually ride on the
water. This can happen if the road is wet enough and
you are going fast enough. When your vehicle is
hydroplaning, it has little or no contact with the road.
Hydroplaning does not happen often. But it can if your
tires do not have much tread or if the pressure in
one or more is low. It can happen if a lot of water is
standing on the road. If you can see reections
from trees, telephone poles, or other vehicles, and
raindrops dimple the water’s surface, there could be
hydroplaning.
Hydroplaning usually happens at higher speeds. There
just is not a hard and fast rule about hydroplaning.
The best advice is to slow down when it is raining.
Driving Through Deep Standing Water
Notice:If you drive too quickly through deep
puddles or standing water, water can come in
through your engine’s air intake and badly damage
your engine. Never drive through water that is
slightly lower than the underbody of your vehicle. If
you cannot avoid deep puddles or standing water,
drive through them very slowly.
Driving Through Flowing Water
{CAUTION:
Flowing or rushing water creates strong forces.
If you try to drive through owing water, as you
might at a low water crossing, your vehicle can
be carried away. As little as six inches of
owing water can carry away a smaller vehicle.
If this happens, you and other vehicle
occupants could drown. Do not ignore police
warning signs, and otherwise be very cautious
about trying to drive through owing water.
Some Other Rainy Weather Tips
Besides slowing down, allow some extra following
distance. And be especially careful when you pass
another vehicle. Allow yourself more clear room
ahead, and be prepared to have your view restricted
by road spray.
Have good tires with proper tread depth. SeeTires
on page 5-54.
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