2004 CHEVROLET CLASSIC service

Speedometer and Odometer
Your speedometer lets you see your speed in miles per
hour (mph).
Your odometer shows how far your vehicle has been
driven in miles.
Your vehicle has a tamper resistant odometer. The
digital odometer will read 999,999 if someone tries to
turn it back.
Repair or replacement of you instrument panel cluster
should only be performed by an authorized GM
service center.
Trip Odometer
The trip odometer can tell
you how far you have
driven since you last reset
it.
The reset button is located next to the trip odometer. To
reset the trip odometer to zero, press and hold the
reset button for one or two seconds. Also, by pressing
this button, you can toggle between the odometer
and the trip odometer.
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Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows the air bag symbol. The system
checks the air bag’s electrical system for malfunctions.
The light tells you if there is an electrical problem.
The system check includes the air bag sensor, the air
bag modules, the wiring and the crash sensing and
diagnostic module. For more information on the air bag
system, seeSupplemental Restraint System (SRS)
on page 1-56.
This light will come on
when you start your
vehicle, and it will flash for
a few seconds. Then the
light should go out. This
means the system is ready.
If the air bag readiness light stays on after you start the
vehicle or comes on when you are driving, your air
bag system may not work properly. Have your vehicle
serviced right away.{CAUTION:
If the air bag readiness light stays on after you
start your vehicle, it means the air bag system
may not be working properly. The air bags in
your vehicle may not inate in a crash, or they
could even inate without a crash. To help avoid
injury to yourself or others, have your vehicle
serviced right away if the air bag readiness light
stays on after you start your vehicle.
The air bag readiness light should flash for a few
seconds when you turn the ignition key to ON. If the
light doesn’t come on then, have it fixed so it will
be ready to warn you if there is a problem.
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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
floor. It may take longer to stop. If the light is still on,
have the vehicle towed for service. SeeTowing
Your Vehicle on page 4-29.
{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.
Anti-Lock Brake System Warning
Light
If your vehicle has the
anti-lock brake system, the
light will come on when
your engine is started and
may stay on for several
seconds. That’s normal.
If the light stays on, turn the ignition to OFF. Or, if the light
comes on and the chime sounds when you’re driving,
stop as soon as possible and turn the ignition off. Then
start the engine again to reset the system. If the light still
stays on, or comes on again while you’re driving, your
vehicle needs service. 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. See
Brake System Warning Light on page 3-27earlier in this
section.
The anti-lock brake system warning light will come on
briefly when you turn the ignition key to ON. This is
normal. If the light doesn’t come on then, have it fixed
so it will be ready to warn you if there is a problem.
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Engine Coolant Temperature Gage
This gage shows the
engine coolant
temperature.
If the gage pointer moves into the red area, the light
comes on and you hear a chime, your engine is too hot!
It means that your engine coolant has overheated.
If you have been operating your vehicle under normal
driving conditions, you should pull off the road, stop your
vehicle and turn off the engine as soon as possible.
SeeEngine Overheating on page 5-22.
Low Coolant Warning Light
This light comes on
briefly when you turn
your ignition ON.
If this light comes on and stays on, the coolant level in
your vehicle is low. SeeEngine Coolant on page 5-19.
If the light is on along with an overheat warning,
you may have a serious overheating problem, see
Engine Coolant Temperature Gage on page 3-29.
Notice:If you operate the engine without coolant
or fail to maintain the cooling system properly,
you could damage the engine. The repairs would not
be covered by your warranty. Always follow the
maintenance schedule in this manual for
maintaining your cooling system. SeeCooling
System on page 5-25for more information.
SeeEngine Overheating on page 5-22for information
on what to do. Your vehicle should be serviced as soon
as possible.
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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,
transaxle, 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.
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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 misfire condition has been
detected. A misfire 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.
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 flashing and remains on steady, see “If
the Light Is On Steady” following.If the light continues to flash, 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
flashing, 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 5-7. 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 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.
3-31

Oil Pressure Light
If you have a low engine
oil pressure problem, this
light will stay on after
you start your engine, or
come on and you will hear
a chime when you are
driving.
This indicates that your engine is not receiving enough
oil. The engine could be low on oil, or could have
some other oil problem. Have it fixed immediately.
When the ignition is on but the engine is not running,
the light will come on as a test to show you it is working,
but the light will go out when the engine is running. If
it doesn’t come on with the ignition on, you may have a
problem with the bulb. Have it fixed right away.{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.
3-33

Service Vehicle Soon Light
This light will come on
briefly when you turn the
ignition to ON.
It will stay on, or come on and a chime will sound if it
detects a problem on the vehicle, such as a Daytime
Running Lamps (DRL) or an automatic headlamp
system malfunction. If this happens, see your dealer as
soon as possible.
Fuel Gage
Your fuel gage tells you
about how much fuel you
have left, when the
ignition is on.
When the indicator nears empty, the light will come on
and you will hear a chime. You still have a little fuel
left, but you should get more soon.
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