2003 CHEVROLET TAHOE brake

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. Park the vehicle with the ignition off and the
transmission in PARK (P).
2. Turn the ignition to RUN; do not start the engine.
3. Apply the brake pedal, shift into NEUTRAL (N),
press the accelerator pedal to the ¯oor and then
press the TAS on/off button and hold it down for at
least six seconds.
4. Release the TAS button and both pedals.
5. Turn off the ignition 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 on/off button.
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.
StabilitrakžSystem
Your vehicle is equipped with the Stabilitrakžwhich
combines antilock brake, traction and stability control
systems and helps the driver maintain directional control
of the vehicle in most driving conditions.
When you ®rst start your vehicle and begin to drive
away, the system performs several diagnostic checks to
insure there are no problems. You may hear or feel
the system working. This is normal and does not mean
there is a problem with your vehicle. The system
should initialize before the vehicle reaches 20 m.p.h.
(32 km/h). In some cases, it may take approximately two
miles of driving before the system initializes.
If the system fails to turn on or activate, the STABILITY
SYS DISABLED or SERVICE STABILITY message
will be displayed. If the vehicle has gone through heavy
acceleration or braking during the ®rst two miles after
starting your vehicle, the STABILITY SYS DISABLED
message may appear. If this is the case, your
vehicle does not need servicing. Turn your vehicle off
and back on again to reset the system. If either message
appears on the Driver Information Center (DIC), and
your vehicle hasn't gone through hard acceleration
or braking in the ®rst two miles, your vehicle should be
taken in for service.
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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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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 not; there is not
room. That is 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 4-6. 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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·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
ªrunning startº 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 ifyour 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
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
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 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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Q:What should I do if my vehicle stalls, or is
about to stall, and I can't 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's what you
shoulddo:
·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'll 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'll be able to tell if your wheels
are straight and maneuver as you back down.
It's 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 you
must 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 ªrev-upº the engine and regain
forward momentum. This won't 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's steep enough to
cause you to roll over if you turn around. If you can't
make it up the hill, you must back straight down
the hill.
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Q:Suppose, after stalling, I try to back down
the hill and decide I just can't do it. What
should I do?
A:Set the parking brake, put your transmission in
PARK (P) and turn off the engine. Leave the
vehicle and go get some help. Exit on the uphill
side and stay clear of the path the vehicle
would take if it rolled downhill. Do not shift the
transfer case to NEUTRAL when you leave
the vehicle. Leave it in some gear.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). This is because
the NEUTRAL position on the transfer case
overrides the transmission. You or someone
else could be injured. If you are going to leave
your vehicle, set the parking brake and shift
the transmission to PARK (P). But do not shift
the transfer case to NEUTRAL. Leave the
transfer case in the 2 Wheel High, 4 High or 4
Low position.
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