2004 CHEVROLET IMPALA light

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 briey when you start the engine
just to let you know they’re 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’s 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’re a big help.
Your vehicle may also have a Driver Information
Center (DIC) that works along with the warning lights
and gages. SeeDriver Information Center (DIC)
on page 3-52.
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Tachometer
Your vehicle may have a
tachometer that displays
the engine speed in
thousands of revolutions
per minute (rpm).
Notice:If you operate the engine with the
tachometer in the shaded warning area, your vehicle
could be damaged, and the damages would not
be covered by your warranty. Do not operate
the engine with the tachometer in the shaded
warning area.
Safety Belt Reminder Light
When the key is turned to ON, a chime will come on for
about 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 ash for several more.
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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 sensors, the air
bag modules, the wiring and the crash sensing and
diagnostic module. For more information on the air bag
system, seeAir Bag Systems on page 1-51.This light will come on
when you start your
vehicle, and it will ash 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.
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{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 ash for a few
seconds when you turn the ignition key to ON. If the
light doesn’t come on then, have it xed so it will
be ready to warn you if there is a problem.
Brake System Warning Light
Your vehicle’s hydraulic brake system is divided into two
parts. If one part isn’t working, the other part can still
work and stop you. For good braking, though, you need
both parts working well.
If the warning light comes on, there is a brake problem.
The LOW BRAKE FLUID message in the message
center will also appear when there is a brake problem.
SeeLow Brake Fluid Warning Message on page 3-51.
Have your brake system inspected right away.
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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 gage shows the engine coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During the majority of the operation, the
gage will read 210°F (100°C) or less.
If you are pulling a load or going up hills, it is normal
for the temperature to uctuate and approach the
250°F (122°C) mark. When the gage reads greater than
250°F (122°C), the HOT COOLANT TEMP light will
be illuminated in the message center and a chime
will sound continuously. If the gage reaches the
260°F (125°C) mark, it indicates that the cooling
system is working beyond its capacity.
SeeEngine Overheating on page 5-32.Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped with a computer which
monitors operation of the fuel, ignition and emission
control systems.United States
Canada
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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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