2003 CHEVROLET TAHOE light

Traction Assist System (TAS)
Your 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 traction control system is enabled every time your
vehicle is started. The system will activate if it senses
that any of the wheels are spinning or beginning to lose
traction.
You may hear or feel the system working or notice a
lack of accelerator response, 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 off light
is on, the TAS is off and
will not limit wheel
spin. Adjust your driving
accordingly.
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The traction off light will come on under the following
conditions:
·The Traction Assist System is turned off, either by
pressing the TAS on/off button or turning off the
automatic engagement feature of the TAS.
·The transmission is in FIRST (1); 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.
·If the vehicle has been driven with the TAS system
on for long periods of time, or if the vehicle has
gone through many several high speed braking
maneuvers the system may be automatically
disabled. The system will automatically re-enable
after approximately two minutes of not using
the brakes.
See
Traction Off Light on page 3-44.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. See ªRocking Your Vehicleº under
If You
Are Stuck: In Sand, Mud, Ice or Snow on page 4-56.
To turn the system on or
off, press the TAS on/off
button located on the
instrument panel.
If you used the button to turn the system off, the traction
off light will come on and stay on. You can turn the
system back on at any time by pressing the button
again. The traction off light should go off.
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The STABILITY SYS ACTIVE message will appear on
the Driver Information Center (DIC) only when the
system is both on and activated. You may also feel or
hear the system working; this is normal. For more
information on the stability messages, see
Driver
Information Center (DIC) on page 3-53.
The Stabilitrak
žmode
button is located on the
instrument panel.
Stabilitrak
žand part of the traction control system can
be turned off or back on by pressing the
Stabilitrak
žbutton. All-wheel drive vehicles must be in
all-wheel drive mode to turn the system on or off.
When the system is turned off, the traction off light will
illuminate, and the STABILITY SYS DISABLED
message will appear on the DIC to warn the driver that
both the stability system and part of the traction
control system are disabled. Your vehicle will still have
brake-traction control when Stabilitrak
žis off, but
will not be able to use the engine speed management
system. See ªTraction Control Operationº next for
more information.When the Stabilitrak
žsystem has been turned off you
may still hear system noises as a result of the
brake-traction control coming on.
It is recommended to leave the system on for normal
driving conditions, but it may be necessary to turn
the system off if your vehicle is stuck in sand, mud, ice
or snow, and you want to ªrockº your vehicle to
attempt to free it. It may also be necessary to turn off
the system when driving in extreme off-road conditions
where high wheel spin is required. See
If You Are
Stuck: In Sand, Mud, Ice or Snow on page 4-56.
When the transfer case is in 4 low, the stability system
is automatically disabled, and the STABILITY SYS
DISABLED message will appear on the DIC. In 4 low,
the Stabilitrak
žbutton only turns the traction control
system on and off.
Traction Control Operation
The traction control system is part of the
Stabilitrakžsystem. Traction control limits wheel spin by
reducing engine power to the wheels (engine speed
management) and by applying brakes to each individual
wheel (brake-traction control) as necessary.
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The traction control system is enabled automatically
when you start your vehicle, and it will activate and
display the TRACTION ACTIVE message in the Driver
Information Center (DIC) if it senses that any of the
wheels are spinning or beginning to lose traction while
driving. If you turn off Stabilitrak
ž, only the brake-traction
control portion of traction control will work. The engine
speed management will be disabled. In this state, engine
power is not reduced automatically and the driven wheels
can spin more freely. This can cause the brake-traction
control to activate constantly. For more information on the
traction active message, see
Driver Information Center
(DIC) on page 3-53.
Notice:If the traction off light comes on due to
heavy braking and/or because the traction control
system has been continuously active, do not
allow the wheel(s) of one axle to spin excessively.
If you do, you may be causing damage to your
transfer case. This could lead to costly repairs not
covered by your warranty.
If the brake-traction control system activates constantly
or if the brakes have heated up due to high speed
braking, the brake-traction control will be automatically
disabled. The system will come back on after the
brakes have cooled. This can take up to two minutes or
longer depending on brake usage.
Notice:Don't allow the wheel(s) of one axle to spin
excessively when the traction off, ABS and brake
lights are on and the SERVICE STABILITY MESSAGE
is displayed. In this situation, damage to the
transfer case is possible. This could lead to costly
repairs not covered by your warranty. You should
immediately reduce engine power until the lights
and messages are no longer displayed.
The traction control system may activate on dry or
rough roads or under conditions such as heavy
acceleration while turning or abrupt upshifts/downshifts
of the transmission. When this happens you may
notice a reduction in acceleration, or may hear a noise
or vibration. This is normal.
If your vehicle is in cruise control when the system
activates, the STABILITY SYS ACTIVE message will
appear on the Driver Information Center and the cruise
control will automatically disengage. When road
conditions allow you to use cruise again, you may
re-engage the cruise control. See ªCruise Controlº under
Turn Signal/Multifunction Lever on page 3-7
Stabilitrakžmay also turn off automatically if it determines
that a problem exists with the system. If the problem does
not clear itself after restarting the vehicle, you should see
your dealer for service.
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QUADRASTEERŸ
The QUADRASTEERŸ System has a control and
diagnostic module that monitors and records current
system status and operational information.
If your vehicle is equipped with the 4 Wheel Steer
system it has the ability to steer the vehicle with all four
wheels.
Once the 4 Wheel Steer mode is selected, it is
recommended to leave the vehicle in this mode at all
times, and during all driving and weather conditions.
You can select this mode at any speed, however, if you
are turning the system will not engage until the turn
is complete.
The 4 Wheel Steer system is equipped with three
different driving modes:
·Two wheel steering (2)
·Four wheel steering (4)
·Four wheel steering with a trailer mode (_)The switch is located on the instrument panel.
2:In this mode the vehicle will operate like any other
vehicle with two wheel steering. If you want to use 2
wheel steer mode and your vehicle is not in this mode,
press the button until the 2 indicator, located to the right
of the 4 Wheel Steer button, lights up. If the 2 indicator is
¯ashing you will have to center the steering wheel by
turning it to the left or right.
Your vehicle will return to 2 when the transmission is
shifted into NEUTRAL, for example when entering a
car wash.
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To engage the 4 Wheel Steer tow mode, press the
button until the 4 and tow mode indicators light up on
the instrument panel. If the tow indicator is ¯ashing you
will have to center the steering wheel by turning it to
the left or right. While in the 4 wheel steer tow mode, it
is possible the steering wheel may be slightly off
center. For more information, see
Towing a Trailer on
page 4-65.
Car Washes for QUADRASTEERŸ
Equipped Vehicles
Notice:Because your vehicle has a wider rear
track a small number of older car washes may be
too narrow for your vehicle. Conveyor systems
on some automatic car washes may damage your
vehicle. Only use conveyor system car washes with
13-inch (33 cm) wide conveyor rails and/or
stationary washes with at least 82 inches (208 cm)
between the rails. Before using the car wash
check with the manager.
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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.
Passing
The driver of a vehicle about to pass another on a
two-lane highway waits for just the right moment,
accelerates, moves around the vehicle ahead, then
goes back into the right lane again. A simple maneuver?
Not necessarily! Passing another vehicle on a two-lane
highway is a potentially dangerous move, since the
passing vehicle occupies the same lane as oncoming
traffic for several seconds. A miscalculation, an error in
judgment, or a brief surrender to frustration or anger
can suddenly put the passing driver face to face with the
worst of all traffic accidents Ð the head-on collision.
So here are some tips for passing:
·ªDrive ahead.º Look down the road, to the sides
and to crossroads for situations that might affect
your passing patterns. If you have any doubt
whatsoever about making a successful pass, wait
for a better time.
·Watch for traffic signs, pavement markings and
lines. If you can see a sign up ahead that might
indicate a turn or an intersection, delay your pass.
A broken center line usually indicates it is all
right to pass (providing the road ahead is clear).
Never cross a solid line on your side of the lane or
a double solid line, even if the road seems empty
of approaching traffic.
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Surface Obstacles:Unseen or hidden obstacles can
be hazardous. A rock, log, hole, rut or bump can startle
you if you're 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's 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're 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't control
the vehicle as well or at all.Because you will be on an unpaved surface, it's
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 isn't.
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 re¯exes, perceptions and judgment can be
affected by even a small amount of alcohol. You
could have a serious Ð or even fatal Ð accident if you
drink and drive or ride with a driver who has been
drinking. See
Drunken Driving on page 4-2.
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