2004 CHEVROLET CORVETTE check engine light

If the Light Is On Steady
You also 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.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.
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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.
Engine Oil Pressure Gage
The engine oil pressure gage shows the engine oil
pressure in psi (pounds per square inch) or kPa
(kilopascals) when the engine is running.
Oil pressure should be 20 to 80 psi (140 to 550 kPa). In
certain situations such as long, extended idles on hot
days, it could read as low as 6 psi (40 kPa) and still be
considered normal. It may vary with engine speed,
outside temperature and oil viscosity, but readings
above the shaded area show the normal operating
range. Readings in the shaded area tell you that
the engine is low on oil, or that you might have some
other oil problem. SeeEngine Oil on page 5-13. United States
Canada
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The engine oil pressure can also be displayed using the
GAGES button on the Driver Information Center (DIC).
SeeDriver Information Center (DIC) on page 3-48.
{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.
Security Light
This light comes on to
remind you to arm your
theft-deterrent system. If it
comes on and stays on
when your ignition is
on, there may be a
problem with your
theft-deterrent system.
SeeTheft-Deterrent System on page 2-16and
PASS-Key
®on page 2-18.
3-45

Check Gages Warning Light
This light will come on
briefly when you are
starting the engine. If the
light comes on and
stays on while you are
driving, check your gages
to see if they are in the
warning areas.
This light can come on for the following reasons:
•Low Oil Pressure
•High Coolant Temperature
•High or Low Battery Voltage
•Low Fuel Level
Fuel Gage
Your fuel gage tells you
about how much fuel you
have left when the
ignition is on.
When the needle approaches the red zone, RESERVE
FUEL will appear on the Driver Information Center (DIC)
display. When the needle approaches the E, LOW
FUEL will appear on the display. At this time, you still
have a little fuel left, but you should get more soon.
Press RESET to acknowledge a DIC message(s).
Pressing RESET will also turn off a DIC message but
the LOW FUEL message will come on again in
10 minutes if you have not added fuel to the vehicle.
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CHARGE SYSTEM FAULT:Press RESET to
acknowledge that you have read the message and to
remove it from the display. The message will reappear
every 10 minutes until this condition changes. You
will hear two chimes when this message is displayed.
If this message comes on while you are driving, you may
have a problem with the electrical charging system. It
could indicate that you have a loose or broken drive belt
or another electrical problem. Have it checked right
away. Driving while this light is on could drain your
battery.
If you must drive a short distance with the message on,
be certain to turn off your accessories, such as the
radio and air conditioner.
COMPETITIVE DRIVING:When the Competitive
Driving mode is selected, this message will be displayed
in the DIC. The instrument panel cluster light will not
be on when the Competitive Driving mode is selected.
The Traction Control System will not be operating
while in the Competitive Driving mode. You should
adjust your driving accordingly.COOLANT OVER TEMP:You will hear four chimes
and the CHECK GAGES telltale will come on when this
message is displayed. To acknowledge the warning,
press the RESET button. After you press the RESET
button, a message will be displayed and you will hear a
chime every minute until this condition changes. If
you do not press RESET, the message will remain on
the digital display until the condition changes.
If the engine coolant exceeds 255°F (124°C), this
message is displayed. 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. You can monitor the coolant
temperature with the GAGES button on the DIC or
the engine coolant gage on the instrument panel cluster.
SeeEngine Overheating on page 5-26.
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LOW OIL LEVEL:Press RESET to acknowledge that
you have read the message and to remove it from
the display. The message will reappear every
10 minutes until this condition changes. Once the
vehicle senses a temperature change in the engine oil,
the light will remain off.
You will hear two chimes when this message is
displayed. If this message appears after starting your
engine, your engine oil level may be too low. You
may need to add oil. SeeEngine Overheating on
page 5-26.
LOW OIL PRESSURE:You will hear four chimes and
the CHECK GAGES telltale will come on when this
message is displayed. To acknowledge the warning,
press the RESET button. After you press the RESET
button, a message will be displayed and you will hear a
chime every minute until the vehicle is serviced. If
you do not press RESET, the message will remain on
the digital display until the vehicle is serviced.
Low oil pressure may be the result of a combination of
low oil level and abrupt changes in the vehicle’s
direction. When this warning is displayed, you should
not operate the engine at high rpm or make fast abrupt
moves. As soon as possible, you should check the
oil level. SeeEngine Oil on page 5-13.LOW TIRE PRESSURE (Except Z06):You will hear
two chimes when this message is displayed. To
acknowledge the warning, press RESET. After you
press RESET, a message will appear every 10 minutes
until this condition changes. This message indicates
that the pressure in one of your tires is less than 25 psi
(172 kPa). Next to the LOW TIRE PRESSURE
message, you can see either LF (left front), LR (left
rear), RF (right front) or RR (right rear) to indicate to you
which tire is low on pressure. You can receive more
than one tire pressure message at a time. To read other
messages that may have been sent at the same time,
press RESET. If a tire pressure message appears on the
DIC, stop as soon as you can. Have the tire pressures
checked and set to those shown on your Tire Loading
Information Label. SeeExtended Mobility Tires
(Except Z06) on page 5-61andTire Pressure
Monitor Operation (Except Z06) on page 5-64.
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REDUCED ENGINE POWER:You will hear chimes
continuously when this message is displayed. To
acknowledge that you have read the message and to
remove it from the display, press RESET. The message
will reappear every 15 seconds until this condition
changes.
If the Driver Information Center (DIC) displays the
REDUCED ENGINE POWER message and the CHECK
ENGINE light comes on, a noticeable reduction in the
vehicle’s performance may occur. If the REDUCED
ENGINE POWER message is displayed but there is no
reduction in performance, proceed to your destination.
The performance may be reduced the next time
the vehicle is driven.
The vehicle may be driven at a reduced speed while the
REDUCED ENGINE POWER message is displayed,
but acceleration and speed may be reduced. Anytime
the CHECK ENGINE light stays on, the vehicle
should be taken to an authorized dealer as soon as
possible for diagnosis and repair.
Also, refer toMalfunction Indicator Lamp on page 3-41.
If the REDUCED ENGINE POWER message is
displayed in combination with the COOLANT OVER
TEMP message, seeEngine Overheating on page 5-26.REDUCE ENGINE RPM:You will hear four chimes
when this message is displayed. To acknowledge
the warning, press the RESET button. After you press
the RESET button, a message will be displayed and you
will hear a chime every minute until this condition
changes. If you do not press RESET, the message will
remain on the digital display until the condition
changes.
If the engine oil temperature exceeds 320°F (160°C),
this message is displayed. You should check the engine
coolant temperature and engine oil level. If your
engine is too hot, seeEngine Overheating on page 5-26.
Your vehicle may need service, so see your dealer.
You can monitor the oil temperature with the GAGES
button on the DIC.
SERVICE ABS (Anti-Lock Brake System):If the
SERVICE ABS message is displayed when you
are driving, stop as soon as possible and turn the
ignition off. Then start the engine again to reset the
system. If the message stays on, or comes back
on again while you are driving, your vehicle is in need
of service. If the regular brake system warning light
is not on, you still have brakes, but do not have anti-lock
brakes. If the regular brake system light is also on,
you do not have anti-lock brakes and there is a problem
with your brakes. SeeBrake System Warning Light
on page 3-38.
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Avoid needless heavy braking. Some people drive in
spurts — heavy acceleration followed by heavy
braking — 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 traffic and 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 (ABS)
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, and you may even notice that your
brake pedal moves a little. This is normal.
If there is a problem with
the anti-lock brake system,
this warning light will
stay on. SeeAnti-Lock
Brake System Warning
Light on page 3-39.
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