2004 CHEVROLET SILVERADO service

Traction Off Light
If you have the Traction
Assist System, this light
should come on briey
when you turn the ignition
to RUN.
If the light doesn’t come on then, the system may
require service; have it xed so it will be there to warn
you if the system is turned off.
If the light stays on, or comes on when you’re driving,
there may be a problem with your Traction Assist
System and your vehicle may need service. When this
light is on, the system will not limit wheel spin. Adjust
your driving accordingly.
The traction off light may come on for the
following reasons:
If you turn the system off by pressing the TAS
on/off button located to the left of the steering wheel,
the light will come on and stay on. To turn the
system back on, press the button again; the light
should go off.
If you move the shift lever to FIRST (1), the light
will come on and stay on to indicate that the
traction system is off. This is normal operation. To
turn the system back on, move the shift lever
back to a position other than FIRST (1); the light
should go off. SeeTraction Assist System (TAS) on
page 4-9.
The light will come on and stay on if the TAS
automatic engagement feature has been turned off.
To turn the system on, press the TAS off/on
button; the light should go off. To turn the automatic
engagement feature back on, seeTraction Assist
System (TAS) on page 4-9.
If the Traction Assist System is affected by an
anti-lock brake system, TAS or engine-related
problem, the system will turn off and the light will
come on. Have your vehicle serviced.
If the vehicle is driven over an extremely rough
road, the system will turn off and the light will
come on. The light will go off a few seconds after
the rough road conditions go away or when
the vehicle comes to a complete stop. This is
normal operation.
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SeeDriver Information Center (DIC) on page 3-53for
further information.
If your vehicle has an Allison transmission, and the uid
reaches temperatures of approximately 275°F (135°C)
or greater, the driver information center will display
a TRANS HOT IDLE ENGINE warning message and a
chime will sound until the temperature falls below
265°F (129°C). Pull the vehicle off the roadway when it
is safe to do so. Set the parking brake, place the
transmission in PARK (P) and allow the engine to idle
until the transmission temperature falls below 265°F
(129°C). If the transmission continues to operate above
265°F (130°C), contact your nearest dealer or the
GM Roadside Assistance Center. SeeRoadside
Assistance Program on page 7-6.
Notice:If you drive your vehicle with the
transmission temperature gage above normal
operating range, you can damage the transmission.
This could lead to costly repairs that would not
be covered by your warranty. Do not drive your
vehicle while the transmission temperature gage
reading is above normal. See your dealer for service.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 (if equipped).
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, seeScheduled Maintenance
on page 6-4for the proper transmission
maintenance intervals.
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Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with a computer which
monitors operation of the
fuel, ignition, and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping to produce a cleaner
environment. The check engine light comes on to
indicate that there is a problem and service is required.
Malfunctions often will be indicated by the system
before any problem is apparent. This may prevent more
serious damage to your vehicle. This system is also
designed to assist your service technician in correctly
diagnosing any malfunction.
Notice:If you keep driving your vehicle with this
light on, after a while, your emission controls
may not work as well, your fuel economy may not
be as good, and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of
your vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test.
This light should come on, as a check to show you it is
working, when the ignition is on and the engine is
not running. If the light does not come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and may damage the emission control system on
your vehicle. Diagnosis and service may be
required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
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If the Light is Flashing
The following may prevent more serious damage to
your vehicle:
Reducing vehicle speed
Avoiding hard accelerations
Avoiding steep uphill grades
If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible
If the light stops ashing and remains on steady, see “If
the Light Is On Steady” following.
If the light continues to ash, when it is safe to do so,
stop the vehicle. Find a safe place to park your vehicle.
Turn the key off, wait at least 10 seconds and restart
the engine. If the light remains on steady, see “If
the Light Is On Steady” following. If the light is still
ashing, follow the previous steps, and see your dealer
for service as soon as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. SeeFilling Your Tank on page 5-9. The
diagnostic system can determine if the fuel cap hasbeen 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 off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-5. Poor fuel quality will
cause your engine not to run as efficiently as designed.
You may notice this as stalling after start-up, stalling
when you put the vehicle into gear, misring, hesitation
on acceleration, or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the
light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer can check the vehicle. Your dealer has
the proper test equipment and diagnostic tools to
x any mechanical or electrical problems that may
have developed.
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A reading in the low pressure zone may be caused by a
dangerously low oil level or some other problem
causing low oil pressure. Check your oil as soon as
possible. SeeOil Pressure LowunderDIC Warnings
and Messages on page 3-64andEngine Oil on
page 5-20.
{CAUTION:
Do not keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be
covered by your warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
Cruise Control Light
The cruise light comes on
whenever you set your
cruise control. See “Cruise
Control” underTurn
Signal/Multifunction Lever
on page 3-7.
Four-Wheel-Drive Light
The four-wheel drive
indicator will light up when
you shift a manual
transfer case into
four-wheel drive and the
front axle engages.
Some delay between shifting and the indicator’s
lighting is normal.
SeeFour-Wheel Drive on page 2-36for
more information.
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C (Personalization):This button will change personal
options available on your vehicle.
D (Select):This button resets certain functions and
turns off or acknowledges messages on the DIC.
If your vehicle is not equipped with the DIC steering
wheel buttons you will not have all of the features listed
above, and you will turn off, or acknowledge DIC
messages by using the trip odometer reset stem located
on the instrument panel cluster.
DIC Operation and Displays
The DIC comes on when the ignition is on. After a short
delay the DIC will display the current driver (1 or 2)
and the information that was last displayed before the
engine was turned off.
If a problem is detected, a warning message will appear
on the display. Pressing any of the four buttons will
acknowledge (clear) most current warnings or service
messages. Some warnings that cannot be
acknowledged (cleared) are: ENGINE OVERHEATED,
OIL PRESSURE LOW, REDUCED ENGINE POWER,
TRANS HOT IDLE ENGINE. These warnings must
be dealt with immediately and therefore cannot
be cleared until the problem has been corrected.
The DIC has different modes which can be accessed by
pressing the four buttons on the DIC. These buttons are
trip information, fuel information, personalization and
select. The button functions are detailed in the following.
Trip Information Button
Press the trip information button to scroll through the
ODOMETER, PERSONAL TRIP ON/OFF, BUSINESS
TRIP ON/OFF, HOURMETER, ANNUAL LOG and
TIMER. If the personal trip and/or the business trip are
set to ON, you will also be able to scroll through
more messages. See “Personal Trip” and “Business
Trip” next for more information.
If your vehicle is not equipped with the DIC steering
wheel buttons you can select the trip information
by pressing the trip odometer reset stem on the
instrument panel cluster.
Personal Trip
Turn PERSONAL TRIP on or off by pressing the
select button. When it is on, you will also be able to
scroll through the following by pressing the trip
information button:
PERSONAL: XXXXXX.X MI — This shows the
current distance traveled since the last reset for the
personal trip odometer in either miles or kilometers.
PERSONAL: XXXX.X GAL — This shows the
amount of fuel used for the personal trip.
PERSONAL: XX.X MPG— This shows how
many miles per gallon of fuel your vehicle is getting
for the personal trip based on current and past
driving conditions.
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LEFT REAR DOOR AJAR (Crew Cab)
If the driver’s side rear door is not fully closed, this
message will appear on the display and you will hear a
chime. Stop and turn off the vehicle, check the door
for obstacles, and close the door again. Check to see if
the message still appears on the DIC. Press the
select button to acknowledge the message and clear it
from the DIC display.
LOW COOLANT LEVEL
If your vehicle is equipped with a low coolant level
sensor, this message will appear on the DIC if
the engine coolant level is low. Adding coolant will clear
the message.
OIL PRESSURE LOW
If low oil pressure levels occur, this message will be
displayed on the DIC and a chime will sound. Stop the
vehicle as soon as safely possible and do not operate
it until the cause of the low oil pressure has been
corrected. Check your oil as soon as possible and have
your vehicle serviced. SeeEngine Oil on page 5-20.
OIL LIFE RESET
This message will appear on the display for
about 10 seconds after resetting the change engine
oil message.
PASSENGER DOOR AJAR
If the passenger’s door is not fully closed, this message
will appear on the display and you will hear a chime.
Stop and turn off the vehicle, check the door for
obstacles, and close the door again. Check to see if the
message still appears on the DIC. Press the select
button to acknowledge the message and clear it from
the DIC display.
RANGE SHIFT INHIBITED
(Allison Transmission®Only)
If the transmission is unable to shift into a selected gear
this message will appear on the DIC. The electronic
shift position indicator on the instrument panel cluster
may blink when this occurs. To make the vehicle shift to
the requested gear you may have to shift back to
PARK (P) or NEUTRAL (N) and re-select the
desired gear.
REDUCED ENGINE POWER
This message is displayed when the cooling system
temperature gets too hot and the engine further enters
the engine coolant protection mode.
SeeEngine Overheating on page 5-38for
further information.
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RIGHT REAR DOOR AJAR (Crew Cab)
If the passenger’s side rear door is not fully closed,
this message will appear on the display and you
will hear a chime. Stop and turn off the vehicle, check
the door for obstacles, and close the door again. Check
to see if the message still appears on the DIC. Press
the select button to acknowledge the message and clear
it from the DIC display.
SERVICE AIRBAG
If there is a problem with the air bag system, this
message will be displayed on the DIC. Have a qualied
technician inspect the system for problems. Press
the select button to acknowledge the message and clear
it from the DIC display.
SERVICE BRAKE SYSTEM
If there is a problem with the brake system, this
message will be displayed on the DIC. If this message
appears, stop as soon as possible and turn off the
vehicle. Restart the vehicle and check for the message
on the DIC display. If the message is still displayed,
or appears again when you begin driving, the brake
system needs service.
SERVICE BRAKE BOOSTER
If your vehicle has vaccum assist power brakes, this
message will be displayed on the DIC when there is a
problem with the Supplemental Brake Assist system.
If the message is displayed immediately after starting
the vehicle or the message appears while driving,
your Supplemental Brake Assist system needs service.
SeeBrake System Warning Light on page 3-43.
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