2005 CHEVROLET CLASSIC engine

Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause
an expensive repair or replacement. Paying attention
to your warning lights and gages could also save you
or others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle’s functions. As you
will see in the details on the next few pages, some
warning lights come on briefly when you start the
engine just to let you know they are working. If you
are familiar with this section, you should not be
alarmed when this happens.Gages can indicate when there may be or is a problem
with one of your vehicle’s functions. Often gages
and warning lights work together to let you know when
there is a problem with your vehicle.
When one of the warning lights comes on and stays
on when you are driving, or when one of the gages
shows there may be a problem, check the section
that tells you what to do about it. Please follow
this manual’s advice. Waiting to do repairs can be
costly — and even dangerous. So please get to know
your warning lights and gages. They are a big help.
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Tachometer
The tachometer shows your engine speed in revolutions
per minute (rpm).
Safety Belt Reminder Light
When the key is turned to ON or START, a chime will
come on for several seconds to remind people to fasten
their safety belts, unless the driver’s safety belt is
already buckled.
The safety belt light will
also come on and stay
on for several seconds,
then it will flash for
several more.
If the driver’s belt is already buckled, neither the chime
nor the light will come on.
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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 4-32.
{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. SeeBrake 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.
3-28

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
to ON.
If this light comes on and stays on, the coolant level in
your vehicle is low. SeeEngine Coolant on page 5-18.
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 5-24for 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 awhile, 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.
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.
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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 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 the 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.
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, misfiring, 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 fix any
mechanical or electrical problems that may have
developed.
3-31

Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
may begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.
Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the Check
Engine light is on or not working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen
if you have recently replaced your battery or if your
battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This may take several days
of routine driving. If you have done this and your vehicle
still does not pass the inspection for lack of OBD
system readiness, your GM dealer can prepare the
vehicle for inspection.
Oil Pressure Light
If you have low engine oil
pressure, 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.
This light will come on briefly when you turn on
the ignition as a check to show you it is working. If it
does not come on with the ignition on, you may have
a problem with the bulb. Have it fixed right away.
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{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.
Passlock®Warning Light
This light will come
on when you turn the
ignition to ON. The light
will stay on until the
engine starts.
If the light flashes, the Passlock
®system has entered a
tamper mode. If the vehicle fails to start, seePasslock®
on page 2-15.
If the light comes on continuously while driving and
stays on, there may be a problem with the Passlock
®
system. Your vehicle will not be protected by Passlock®,
and you should see your dealer.
3-33