2003 CHEVROLET SILVERADO engine

TIGHTEN FUEL CAP
If the vehicle's fuel cap is not tightened properly thsi
message may appear along with the check engine light
on the instrument panel. See
Malfunction Indicator
Lamp on page 3-49. Fully reinstall the fuel cap.
SeeFilling Your Tank on page 5-6. The diagnostic
system can determine if the fuel cap has been left off or
improperly installed. A loose or missing fuel cap will
allow fuel to evaporate into the atmosphere. A few
driving trips with the cap properly installed should turn
the light and message off.
TRACTION ACTIVE
When the traction control system had detected that any
of the vehicle's wheels are slipping, the traction
control system will activate and this message will appear
on the DIC. For more information see ªTraction Assistº
in the Index.
TRANSMISSION HOT
If the transmission ¯uid temperature becomes high, the
message center will display this message.
When the transmission enters the protection mode, you
may notice a change in the transmission shifting
patterns. When the transmission ¯uid temperature
returns to normal, the display will turn off and the
transmission shifting patterns will return to normal.
Notice:If you keep driving your vehicle with the
transmission TRANS FLUID HOT message
displayed, you can damage the transmission. This
could lead to costly repairs that may not be covered
under your warranty.
The following situations can cause the transmission to
operate at higher temperatures:
·Towing a trailer
·Hot outside air temperatures
·Hauling a large or heavy load
·Low transmission ¯uid level
·High transmission ¯uid level
·Restricted air ¯ow to the radiator and the auxiliary
transmission oil cooler.
A temporary solution to hotter transmission operating
temperatures may be to let the transmission cool down.
If the transmission is operated at higher temperatures
on a frequent basis, see
Scheduled Maintenance
on page 6-5for the proper transmission maintenance
intervals.
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TRANS HOT IDLE ENGINE (Allison
TransmissionžOnly)
If the transmission ¯uid in the vehicle gets hot, this
message will appear on the DIC, and you will hear a
chime. The chime will stop when the transmission ¯uid
temperature is less that 265ÉF (129ÉC). Driving with
the transmission ¯uid temperature high can cause
damage to the vehicle. Stop the vehicle and let it idle to
allow the transmission to cool. This message will
clear when the ¯uid temperature reaches a safe level.
Notice:If you keep driving your vehicle with
the transmission TRANS HOT¼IDLE ENGINE
message displayed, you can damage the
transmission. This could lead to costly repairs that
may not be covered under your warranty.
TURN SIGNAL ON
If a turn signal is left on for 3/4 of a mile (1.2 km), this
message will appear on the display and you will
hear a chime. Move the turn signal/multifunction lever to
the off position. Press the select button to acknowledge
the message and clear it from the DIC display.
Audio System(s)
Notice:Before you add any sound equipment to
your vehicle ± like a tape player, CB radio, mobile
telephone or two-way radio ± be sure you can
add what you want. If you can, it's very important to
do it properly. Added sound equipment may
interfere with the operation of your vehicle's engine,
radio or other systems, and even damage them.
Your vehicle's systems may interfere with the
operation of sound equipment that has been added
improperly.
So, before adding sound equipment, check with
your dealer and be sure to check federal rules
covering mobile radio and telephone units.
Your audio system has been designed to operate easily
and to give years of listening pleasure. You will get
the most enjoyment out of it if you acquaint yourself with
it ®rst. Figure out which radio you have in your vehicle,
®nd out what your audio system can do and how to
operate all of its controls to be sure you're getting the
most out of the advanced engineering that went into it.
Your vehicle may have a feature called Retained
Accessory Power (RAP). With RAP, you can play your
audio system even after the ignition is turned off.
See ªRetained Accessory Power (RAP)º under
Ignition
Positions on page 2-20.
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Braking
Braking action involvesperception timeandreaction time.
First, you have to decide to push on the brake pedal.
That isperception time.Then you have to bring up your
foot and do it. That isreaction time.
Averagereaction timeis about 3/4 of a second. But that
is only an average. It might be less with one driver
and as long as two or three seconds or more with
another. Age, physical condition, alertness, coordination
and eyesight all play a part. So do alcohol, drugs and
frustration. But even in 3/4 of a second, a vehicle moving
at 60 mph (100 km/h) travels 66 feet (20 m). That
could be a lot of distance in an emergency, so keeping
enough space between your vehicle and others is
important.
And, of course, actual stopping distances vary greatly
with the surface of the road (whether it is pavement
or gravel); the condition of the road (wet, dry, icy); tire
tread; the condition of your brakes; the weight of
the vehicle and the amount of brake force applied.
Avoid needless heavy braking. Some people drive in
spurts Ð heavy acceleration followed by heavy
braking Ð 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 trafficand 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 are driving, brake
normally but do not 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 Brake System
Your vehicle has anti-lock brakes. 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.
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Supplemental Brake Assist System
If your vehicle has vacuum assist power brakes, it is also
equipped with a supplemental brake assist system
that supplies additional vacuum to the vacuum brake
booster if engine vacuum is reduced. Under certain
conditions, the supplemental brake assist system may
run brie¯y after starting your vehicle or when you
apply and release the brake pedal and it may continue
to run even after you have removed your foot from
the brake pedal. When the supplemental brake assist
system is operating, you may hear a motor running
or feel a slight vibration in the steering wheel or brake
pedal. This indicates that the supplemental brake
assist system is working to supply additional vacuum for
your vacuum assist power brakes. This is a normal
operation of your brake system and does not require that
the brake system be serviced.Each time you start your vehicle and accelerate to
10 mph, the supplemental brake assist system
will perform a self-diagnostic check of the system and
you may hear or feel the supplemental brake assist
motor run brie¯y. While you are driving your vehicle, the
supplemental brake assist system monitors itself to
ensure that it is operating properly. If there is a problem
with the supplemental brake assist system, the
SERVICE BRAKE BOOSTER message will be displayed
on the Driver Information Center. See
DIC Warnings
and Messages on page 3-65.
If your supplemental brake assist system runs every
time you apply and release the brake pedal or you notice
that the brake pedal has suddenly become much
harder to push and the vehicle takes longer to stop, you
should have your vehicle serviced as soon as possible.
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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
Cruise ControlunderTurn 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 3-46.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
Rocking Your VehicleunderIf You
Are Stuck: In Sand, Mud, Ice or Snow on page 4-52.
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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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.Manual Selectable Ride
The main function of this system is to provide superior
ride comfort while trailering or fully loaded, as well
as for unloaded driving. This system also helps
to provide:
·Improved trailering stability
·Improved handling response when trailering or fully
loaded
This button is located on
the center of the instrument
panel near the radio. Press
it to activate the selectable
ride setting as desired. An
indicator light near the
button will illuminate
whenever the system is
active.
It is recommended to use this system as follows:
·For optimum ride comfort in an unloaded vehicle
the button should be out and the indicator light
will not be illuminated. This switch position indicates
NORMAL levels of ride control or damping.
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·For optimum ride comfort when trailering, fully
loaded, driving off-road, or when personal
preferences demand more control the button should
be pressed in with the indicator light illuminated.
This switch position indicates FIRM levels of
ride control or damping.
The following guide can also be used to help determine
the best setting.
NORMAL:The indicator light will be off when the
system is in this setting. Use for normal city and highway
driving. Provides a smooth, soft ride when the vehicle
is unloaded.
FIRM (Unloaded):Press the switch to activate this
setting, the indicator light will illuminate. Use this setting
when road conditions or personal preference demand
more control. Provides more ªfeel²or response to
the road conditions.
FIRM (Loaded):Press the switch to activate this
setting, the indicator light will illuminate. Use this setting
to minimize trailer inputs to the vehicle or when the
vehicle is fully loaded. This setting is also appropriate
for off-road driving.
You can select a setting at any time based on road and
trailering conditions to provide the best ride and
handling. Select a new setting whenever driving
conditions change.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.
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 is important to take curves at a reasonable speed.
A lot of the ªdriver lost controlº accidents mentioned on
the news happen on curves. Here is 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 is no traction, inertia will keep
the vehicle going in the same direction. If you have ever
tried to steer a vehicle on wet ice, you will
understand this.
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