service CHEVROLET SILVERADO 2003 1.G Owner's Manual

Readings in the low warning zone may occur when a
large number of electrical accessories are operating in
the vehicle and the engine is left at an idle for an
extended period. This condition is normal since the
charging system is not able to provide full power
at engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.
You can only drive for a short time with the reading
in either warning zone. If you must drive, turn off
all unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.Up-Shift Light
This light is used on some
models with manual
transmissions.
The shift indicator light will help you get the best fuel
economy.
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Brake System Warning Light
With the ignition on, the brake system warning light will
¯ash when you set the parking brake. The light will
¯ash if the parking brake doesn't release fully. If you try
to drive with the parking brake engaged, a chime will
sound when the vehicle speed is greater than
3 mph (5 km/h).
Your vehicle's hydraulic brake system is divided into two
parts. If one part isn't working, the other part can still
work and stop you. For good braking, though, you need
both parts working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have your brake system
inspected right away.This light should come on brie¯y when you turn the
ignition key to RUN. If it doesn't come on then, have it
®xed so it will be ready to warn you if there's a
problem.
If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push. Or, the pedal may go closer to the
¯oor. It may take longer to stop. If the light is still on,
have the vehicle towed for service. See
Towing
Your Vehicle on page 4-55.
{CAUTION:
Your brake system may not be working
properly if the brake system warning light is
on. Driving with the brake system warning light
on can lead to an accident. If the light is still
on after you have pulled off the road and
stopped carefully, have the vehicle towed for
service.
United States
Canada
3-44

Anti-Lock Brake System Warning
Light
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay on for
several seconds.
That's normal. If the light doesn't come on then, have it
®xed so it will be ready to warn you if there is a
problem.If the light stays on, or comes on when you're driving,
your vehicle needs service. You will also hear a
chime sound when the light is on steady. If the regular
brake system warning light isn't on, you still have
brakes, but you don't have anti-lock brakes. If the
regular brake system warning light is also on you don't
have anti-lock brakes and there's a problem with
your regular brakes. In addition to both lights, you will
also hear a chime sound on the ®rst occurrence of
a problem and each time the vehicle is shut off and then
restarted. See
Brake System Warning Light on
page 3-44.
3-45

Traction Off Light
If you have the Traction
Assist System, this light
should come on brie¯y
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. See
Traction Assist System (TAS) on
page 4-10.
·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, see
Traction Assist
System (TAS) on page 4-10.
·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.
3-46

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:Modi®cations 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.
Modi®cations 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 FlashingÐ A mis®re condition has been
detected. A mis®re increases vehicle emissions
and may damage the emission control system on
your vehicle. Diagnosis and service may be
required.
·Light On SteadyÐ An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
3-49

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 ªIf
the Light Is On Steadyº 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 ªIf
the Light Is On Steadyº 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. See
Filling Your Tank on page 5-6. 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 5-4. 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, mis®ring, 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.
3-50

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. See
Oil Pressure LowunderDIC Warnings
and Messages on page 3-65andEngine Oil on
page 5-16.
{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:Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.
Cruise Control Light
The cruise light comes on
whenever you set your
cruise control. See ªCruise
Controlº under
Turn
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.
See
Four-Wheel Drive on page 2-33for more
information.
3-52

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 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 DIC buttons will
acknowledge any current warning or service messages.
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.
If your vehicle is not equipped with the DIC steering
wheel buttons not all of the features listed will be
available on your vehicle.
Trip Information Button
Use 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 TripandBusiness Tripnext 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
If the PERSONAL TRIP is on (turn it on or off by
pressing the select button) you will also be able to scroll
through the following:
·PERSONAL: XX MI Ð This shows the current
distance traveled since the last reset for the
personal trip odometer in either miles or kilometers.
·PERSONAL: XX.X GAL Ð This shows the amount
of fuel used for the personal trip.
·PERSONAL: XX.X MPG Ð This shows the amount
of fuel used for the personal trip.
3-55

KEYFOB X BATTERY LOW
If a remote keyless entry transmitter battery is low, this
message will appear on the DIC. The battery needs
to be replaced in the transmitter. Press the select button
to acknowledge the message and clear it from the
DIC display.
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 operateit until the cause of the low oil pressure has been
corrected. Check your oil as soon as possible and have
your vehicle serviced.
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
TransmissionžOnly)
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.
3-67

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.
See
Engine Overheating on page 5-33for further
information.
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 quali®ed
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.
See
Brake System Warning Light on page 3-44.
3-68