2002 CHEVROLET IMPALA service

2-86 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 ªLow Brake Fluid Messageº in the Index.
Have your brake system inspected right away.
United States Canada
This light should come on briefly when you turn
the ignition key to ON. If it doesn't come on then,
have it fixed so it will be ready to warn you if there's
a 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 floor.
It may take longer to stop. If the light is still on, have the
vehicle towed for service. See ªAnti
-Lock Brake
System Warning Lightº and ªTowing Your Vehicleº in
the Index.
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.
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.

2-87
Anti-Lock Brake System Warning Light
(If Equipped)
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 briefly when you turn the ignition key to ON.
If the light doesn't come on then, have it fixed so it will
be ready to warn you if there is a problem.
Traction Control System Warning Light
The traction control system
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. See ªTraction
Control Systemº in the Index for more information.

If there's a brake system problem that is specifically
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.

2-89
Malfunction Indicator Lamp
(Check Engine Light)
United States Canada
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:
Modifications 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 the CHECK ENGINE light to
come on. Modifications 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.

2-90
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 Flashing
-- A misfire condition has been
detected. A misfire increases vehicle emissions and
may damage the emission control system on your
vehicle. Dealer or qualified service center diagnosis
and service may be required.

Light On Steady
-- An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center 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 flashing and remains on steady,
see ªIf the Light Is On Steadyº 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 ªIf the Light
Is On Steadyº following. If the light is still flashing,
follow the previous steps, and drive the vehicle to your
dealer or qualified service center for service.
If the Light Is On Steady
You 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 ªFilling Your Tankº in the Index. 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.

2-91
Are you low on fuel?
As your engine starts to run out of fuel, your engine may
not run as efficiently as designed since small amounts
of air are sucked into the fuel line causing a misfire.
The system can detect this. Adding fuel should correct
this condition. Make sure to install the fuel cap properly.
See ªFilling Your Tankº in the Index. It will take a few
driving trips to turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
ªFuelº in the Index. 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,
have your dealer or qualified service center check the
vehicle. Your dealer has the proper test equipment and
diagnostic tools to fix 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 in order 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, see your dealer or qualified service center to
prepare the vehicle for inspection.

2-92 Low Oil Pressure Message
United States Canada
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 fire. 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.

2-94
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 fill 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 fill
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.
Modes
Service Traction System (If Equipped)
United States Canada
If 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 and then go out. 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.

2-96
Hot Coolant Temp
United States Canada
This message is displayed when the cooling system
temperature gets hot. A chime will sound
continuously, also.
Check the coolant temperature gage and the coolant
level. See ªEngine Coolant,º ªEngine Coolant
Temperature Gageº and ªEngine Overheatingº in the
Index for further information.Low Coolant LevelUnited States Canada
This message is displayed when the cooling system is
low on coolant. Four chimes will also sound.
The engine may overheat. See ªEngine Coolantº in the
Index and have your vehicle serviced as soon as you can.