2004 CHEVROLET IMPALA service

This light should come on briey when you turn the
ignition key to ON. If it doesn’t come on then, have it
xed so it will be ready to warn you if there’s a problem.
When the ignition is on, the brake system warning
light will also come on when you set your parking brake.
The light will stay on if your parking brake doesn’t
release fully. If it stays on after your parking brake is
fully released, it means you have a brake 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. SeeBrake System
Warning Light on page 3-33andTowing Your Vehicle on
page 4-30.{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
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Anti-Lock Brake System Warning
Light
If your vehicle is equipped
with anti-lock brakes, the
anti-lock brake system
warning light should come
on for a few seconds
when you turn the ignition
key to ON.
If the anti-lock brake system warning light stays on
longer than normal after you’ve started your engine, turn
the ignition off. Or, if the light comes on and stays on
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, the anti-lock brake system needs
service and you don’t have anti-lock brakes.
The anti-lock brake system warning light should come
on briey when you turn the ignition key to ON. This
is 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.
Traction Control System (TCS)
Warning Light
Your vehicle may have the
traction control system. If it
does, this warning light
may come on for the
following reasons:
If you turn the system off by pressing the TRAC
OFF button located on the instrument panel, a
chime will sound and the warning light will come on
and stay on. To turn the system back on, press
the button again. The warning light should go off.
If there’s a brake system problem that is specically
related to traction control, the traction control
system will turn off and the warning light will come
on. If your brakes begin to overheat, the traction
control system will turn off and the warning light will
come on until your brakes cool down.
If the traction control system warning light comes on
and stays on for an extended period of time when the
system is turned on, your vehicle needs service.
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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.
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 misre condition has been
detected. A misre 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 ashing and remains on steady, see “If
the Light Is On Steady” 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 “If the Light Is On Steady”
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 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.
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The fuel gage, when the ignition is on, tells you about
how much fuel you have left in your tank.
The gage will rst indicate empty before you are out of
fuel, and you should get more fuel as soon as
possible.
Here are four situations you may experience with your
fuel gage. None of these indicate a problem with the
fuel gage.
At the gas station, the fuel pump shuts off before
the gage reads full.
It takes a little more or less fuel to ll up than the
fuel gage indicated. For example, the gage may
have indicated the tank was half full, but it actually
took a little more or less than half the tank’s
capacity to ll the tank.
The gage goes back to empty when you turn off the
ignition.
The gage pointer moves while cornering, braking or
acceleration.
Message Center
The message center is located below the temperature
gage or the tachometer gage (if equipped) on the
instrument panel cluster. It gives you important safety
and maintenance facts.
Service Traction System Warning
Message
If your vehicle is equipped with the traction control
system and this message appears when you are driving,
there is a problem with your traction control system
and your vehicle is in need of service.United States
Canada
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When this message is displayed, the system will not
limit wheel spin. The message will stay on for
60 seconds. Four chimes will also be heard. Adjust your
driving accordingly.
When the ignition is turned off, this message will be
displayed again for three seconds to remind you
that your traction control system is not working properly.
Be sure to have your vehicle serviced right away.Traction Active Message
If your vehicle is equipped with the traction control
system, this message will stay on a few seconds after
the traction system stops limiting wheel spin.
This message will appear when the traction control
system is limiting wheel spin.United States
Canada
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Low Oil Pressure Message
This message is displayed in the message center when
the engine oil pressure is low. A chime will sound
continuously, also.
If this occurs, you should have your vehicle serviced
immediately.
{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. United States
Canada
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Low Engine Oil Level Message
Your vehicle may be equipped with a low engine oil
level message.
This message is displayed for 60 seconds at the start of
each ignition cycle when the engine oil level is low.
Four chimes will also sound.
When the ignition is turned off, this message will be
displayed again for three seconds to remind you
that your engine oil level is low. Be sure to have your
vehicle serviced right away.
SeeEngine Oil on page 5-18on how to check the oil
level and for what type of oil to add.
Change Engine Oil Message
When this message comes on, it means that service is
required for your vehicle. It will appear for 60 seconds.
SeeScheduled Maintenance on page 6-4and
Engine Oil on page 5-18for more information.
Once the engine oil has been changed, the CHANGE
ENGINE OIL message must be reset. Until it is
reset, this message will be displayed for 60 seconds
each time you start the engine. For more information on
resetting the system, see “How to Reset the Change
Engine Oil Message” underEngine Oil on page 5-18. United States
CanadaUnited StatesCanada
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