2004 CHEVROLET CORVETTE check engine

Engine Coolant Temperature Gage
This gage shows the engine coolant temperature. If the
gage pointer moves into the shaded area, your
engine is too hot.
This 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.
(The larger tic marks are in increments of 30° below
220°F (104°C) and in increments of 10° above
220°F (104°C).)
SeeEngine Overheating on page 5-26for more
information.
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. United States
Canada
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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 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 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.
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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.
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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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HIGH TIRE PRESSURE – (LF, LR, RF, RR)
(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
reappear every 10 minutes until this condition
changes. This message indicates that the pressure in
one of your tires is higher than 42 psi (290 kPa). Next to
the HIGH 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 higher than
42 psi (290 kPa). 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 5-61andInation - Tire
Pressure on page 5-62.HIGH TRANS TEMP (Automatic Transmission
Only):You will hear four chimes when this message is
displayed. To acknowledge this warning, press the
RESET button. After you press the RESET button, the
message will be displayed every 10 minutes until
the condition changes. If you do not press RESET, the
message remains on the display until the condition
changes.
If the transmission fluid temperature rises above 270°F
(132°C) or rises rapidly, this message is displayed.
The transmission may shift gears or apply the torque
converter clutch to reduce the fluid temperature. Driving
aggressively or driving on long hills can cause the
transmission fluid temperature to be higher than normal.
If this message appears, you may continue to drive at
a slower speed. You should also monitor the
transmission fluid temperature and allow it to cool to at
least 230°F (110°C). The transmission fluid temperature
can be monitored with the GAGES button on the
DIC. SeeAutomatic Transmission Fluid on page 5-20.
You should also check the engine coolant temperature.
If it is also hot, seeEngine Overheating on page 5-26.
If the HIGH TRANS TEMP message is displayed during
normal vehicle operation on flat roads, your vehicle
may need service. See your dealer for an inspection.
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