2003 CHEVROLET IMPALA light

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.
See
Low Brake Fluid Warning Message on page 3-47.
Have your brake system inspected right away.
This light should come on brie¯y 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 3-34andTowing Your Vehicle on
page 4-31.
{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've pulled off the road and stopped
carefully, have the vehicle towed for service. United States
Canada
3-34

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 brie¯y 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 speci®cally
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.
3-35

Engine Coolant Temperature GageThis 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 210ÉF (100ÉC) or less.
If you are pulling a load or going up hills, it is normal for
the temperature to ¯uctuate and approach the 250ÉF
(122ÉC) mark. When the gage reads greater than 250ÉF
(122ÉC), the HOT COOLANT TEMP light will be
illuminated in the message center and a chime will
sound continuously. If the gage reaches the 260ÉF
(125ÉC) mark, it indicates that the cooling system is
working beyond its capacity.
See
Engine Overheating on page 5-30.
United States±3400 V6
Engine ClusterUnited States±3800 V6
Engine Cluster
Canada±3400 V6 Engine
ClusterCanada±3800 V6 Engine
Cluster
3-36

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.
Notice:Modi®cations 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.
Modi®cations 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 doesn't come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
·Light FlashingÐ A mis®re condition has been
detected. A mis®re increases vehicle emissions
and may damage the emission control system
on your vehicle. Diagnosis and service may
be required. United States
Canada
3-37

·Light On SteadyÐ 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 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 ªIf
the Light Is On Steadyº 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 ªIf the Light Is On
Steadyº 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. See
Filling 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, mis®ring, 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.
3-38

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 ®x any
mechanical or electrical problems that may have
developed.
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 isdesigned 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.
Cruise Control Light
Tthe CRUISE light comes
on whenever you set your
cruise control. See
ªCruise Controlº under
Turn Signal/Multifunction
Lever on page 3-7.
3-39

Low Fuel Warning Message
This message is displayed when your vehicle is low on
fuel. Four chimes will also sound.
Refer to the fuel gage for a better indication of the
amount of fuel remaining in the fuel tank.
Low Brake Fluid Warning Message
This message will be displayed when your vehicle has a
brake problem. The brake system warning light will
also be illuminated.
If this message appears, the brakes aren't working
properly. You should have your vehicle serviced
immediately. See
Brake System Warning Light on
page 3-34for more information. United States
CanadaUnited StatesCanada
3-47

Driver Information Center (DIC)
If your vehicle is equipped with the DIC, it will show
information about the vehicle and the surroundings. It is
located in the headliner between the sun visors.RESET:You can reset the AVG ECON, FUEL USED
or AVG SPEED trip computer modes by pressing
and holding this button for three seconds while you are
in the mode you wish to reset. A chime will sound to
con®rm that your requested change has been made and
all the segments of the display will brie¯y light up.
To change the display to a metric or English reading,
press the RESET and MODE buttons at the same time.
Hold them down for three seconds, and the display
will change. A chime will be heard to con®rm the
new selection.
The reset button can also be used to manually calibrate
the compass. See ªManual Compass Calibrationº
later in this section.
The reset button can be used to set the compass
zone variation. See ªCompass Varianceº later in
this section. Optional Sunroof Version Shown
3-49