2003 CHEVROLET IMPALA service

Operation Tips
·Clear away any ice, snow or leaves from the air
inlets at the base of the windshield that may
block the ¯ow of air into your vehicle.
·Use of non-GM approved hood de¯ectors may
adversely affect the performance of the system.
·Keep the path under the front seats clear of objects
to help circulate the air inside your vehicle more
effectively.
·If the air¯ow seems low when the fan is at the
highest setting, the passenger compartment
air ®lter, if equipped, may need to replaced. For
more information, see
Passenger Compartment Air
Filter on page 3-26andPart A: Scheduled
Maintenance Services on page 6-4.
Passenger Compartment Air Filter
Your vehicle may be equipped with a passenger
compartment particulate air ®lter. It is located
underneath the hood just below the windshield wiper
arm on the passenger's side of the vehicle, underneath
the air inlet grille.
The ®lter traps most of the pollen from air entering the
Climate Control System. Like your engine's air
cleaner/®lter, it may need to be changed periodically to
insure system performance. For information on how
often to change the passenger compartment air
®lter, see
Scheduled Maintenance on page 6-5.
3-26

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, see
Air 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.
{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 in¯ate in a crash, or they
could even in¯ate 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.
3-33

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

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

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.
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 StatesCanada
United StatesCanada
3-41

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:
Don't 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:Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.
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.
See
Engine Oil on page 5-16on how to check the oil
level and for what type of oil to add. United States
Canada
United StatesCanada
3-43