light CHEVROLET IMPALA 2004 8.G Service Manual

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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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, misring, 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,
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.
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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, your GM dealer can prepare the
vehicle for inspection.Cruise Control Light
The CRUISE light comes
on whenever you set your
cruise control. See
Cruise Control on
page 3-11.
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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. SeeBrake System Warning Light on
page 3-33for more information.
Service Vehicle Soon Message
This message will come on if you have engine problems.
These problems may not be obvious and may not
affect vehicle performance or durability. Consult a
qualied dealership for necessary repairs to maintain
top vehicle performance. United States
CanadaUnited StatesCanada
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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
conrm that your requested change has been made and
all the segments of the display will briey 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 conrm the new
selection.
The reset button can also be used to manually calibrate
the compass. See “Manual Compass Calibration”
later in this section.
The reset button can be used to set the compass zone
variation. See “Compass Variance” later in this section.MODE:Press this button to cycle through three modes
of operation: Off, Compass/Temperature and Trip
Computer mode.
Off:No driver information is displayed in this mode
of operation.
Compass/Temperature Mode:One of eight
compass readings and the outside temperature are
displayed. If the temperature is below 38°F
(3°C), the word ICE is displayed for two minutes.
Trip Computer:Pressing the MODE button cycles
through the ve displays. Press the MODE button
after the last Trip Computer display to return
the DIC to the OFF mode.
Compass Variance
Compass variance is the difference between magnetic
north and geographic north. In some areas of the
country, the difference is great enough to cause the
compass to give false readings. If this occurs, the
compass variance must be set.
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CD Messages
If CHECK CD appears on the display and the CD
comes out, it could be for one of the following reasons:
It is very hot. When the temperature returns to
normal, the CD should play.
You are driving on a very rough road. When the
road becomes smooth, the CD should play.
The CD is dirty, scratched, wet, or upside down.
The air is very humid. If so, wait about an hour and
try again.
There may have been a problem while burning
the CD.
The label may be caught in the CD player.
If the CD is not playing correctly, for any other reason,
try a known good CD.
If any error occurs repeatedly or if an error cannot be
corrected, contact your dealer. If your radio displays an
error message, write it down and provide it to your
dealer when reporting the problem.
Theft-Deterrent Feature
THEFTLOCK®is designed to discourage theft of your
vehicle’s radio. The feature works automatically by
learning a portion of the Vehicle Identication Number
(VIN). If the radio is moved to a different vehicle, it
will not operate and LOCKED will appear on the display.
When the ignition is off and RAP is not active, the
blinking red light indicates that THEFTLOCK
®is armed.
With THEFTLOCK
®activated, the radio will not
operate if stolen.
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Radio Reception
AM
The range for most AM stations is greater than for FM,
especially at night. The longer range can cause
station frequencies to interfere with each other. Static
can occur on AM stations caused by things like
storms and power lines. Try reducing the treble to
reduce this noise.
FM Stereo
FM stereo will give the best sound, but FM signals will
reach only about 10 to 40 miles (16 to 65 km). Tall
buildings or hills can interfere with FM signals, causing
the sound to fade in and out.
XM™ Satellite Radio Service
XM™ Satellite Radio Service gives digital radio
reception from coast to coast. Just as with FM, tall
buildings or hills can interfere with satellite radio signals,
causing the sound to fade in and out. The radio may
display NO SIGNAL to indicate interference.
Care of Your Cassette Tape Player
A tape player that is not cleaned regularly can cause
reduced sound quality, ruined cassettes, or a damaged
mechanism. Cassette tapes should be stored in their
cases away from contaminants, direct sunlight, and
extreme heat. If they are not, they may not operate
properly or may cause failure of the tape player.
The tape player should be cleaned regularly after every
50 hours of use. The radio may display CLEAN to
indicate that the tape player has been used for 50 hours
without resetting the tape clean timer. If this message
appears on the display, the cassette tape player
needs to be cleaned. It will still play tapes, but it should
be cleaned as soon as possible to prevent damage
to the tapes and player. If there is a reduction in sound
quality, try a known good cassette to see if the tape
or the tape player is at fault. If this other cassette has no
improvement in sound quality, clean the tape player.
For best results, use a scrubbing action, non-abrasive
cleaning cassette with pads which scrub the tape
head as the hubs of the cleaner cassette turn. The
recommended cleaning cassette is available through
your dealer.
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Care of Your CDs
Handle CDs carefully. Store them in their original cases
or other protective cases and away from direct
sunlight and dust. If the surface of a CD is soiled,
dampen a clean, soft cloth in a mild, neutral detergent
solution and clean it, wiping from the center to the edge.
Be sure never to touch the side without writing when
handling CDs. Pick up CDs by grasping the outer edges
or the edge of the hole and the outer edge.
Care of Your CD Player
The use of CD lens cleaners for CD players is not
advised, due to the risk of contaminating the lens of the
CD optics with lubricants internal to the CD mechanism.
Backglass Antenna
The AM-FM antenna is integrated with the rear window
defogger, located in the rear window. Be sure that the
inside surface of the rear window is not scratched and
that the lines on the glass are not damaged. If the inside
surface is damaged, it could interfere with radio
reception. Also, for proper radio reception, the antenna
connector at the top-center of the rear window needs to
be properly attached to the post on the glass.Notice:Using a razor blade or sharp object to clear
the inside rear window may damage the rear
window antenna and/or the rear window defogger.
Repairs would not be covered by your warranty.
Do not clear the inside rear window with sharp
objects.
Notice:Do not apply aftermarket glass tinting with
metallic lm. The metallic lm in some tinting
materials will interfere with or distort the incoming
radio reception. Any damage caused to your
backglass antenna due to metallic tinting materials
will not be covered by your warranty.
Because this antenna is built into your rear window,
there is a reduced risk of damage caused by car washes
and vandals.
If you choose to add a cellular telephone to your
vehicle, and the antenna needs to be attached to the
glass, be sure that you do not damage the grid lines for
the AM-FM antenna. There is enough space between
the lines to attach a cellular telephone antenna
without interfering with radio reception.
Do not apply aftermarket glass tinting to the back glass.
The metallic lm in some tinting materials will interfere
with or distort the incoming radio reception. Care
must be taken when cleaning the rear window because
it breaks in the resistive material heating element
and will adversely affect radio and defogger
performance. See your dealer for details.
3-96

Braking
Braking action involvesperception timeand
reaction time.
First, you have to decide to push on the brake pedal.
That isperception time.Then you have to bring up your
foot and do it. That isreaction time.
Averagereaction timeis about 3/4 of a second. But that
is only an average. It might be less with one driver
and as long as two or three seconds or more with
another. Age, physical condition, alertness, coordination
and eyesight all play a part. So do alcohol, drugs and
frustration. But even in 3/4 of a second, a vehicle moving
at 60 mph (100 km/h) travels 66 feet (20 m). That
could be a lot of distance in an emergency, so keeping
enough space between your vehicle and others is
important.
And, of course, actual stopping distances vary greatly
with the surface of the road (whether it is pavement
or gravel); the condition of the road (wet, dry, icy); tire
tread; the condition of your brakes; the weight of
the vehicle and the amount of brake force applied.
Avoid needless heavy braking. Some people drive in
spurts — heavy acceleration followed by heavy
braking — rather than keeping pace with traffic. This is
a mistake. Your brakes may not have time to cool
between hard stops. Your brakes will wear out much
faster if you do a lot of heavy braking. If you keep pacewith the traffic and allow realistic following distances,
you will eliminate a lot of unnecessary braking.
That means better braking and longer brake life.
If your engine ever stops while you are driving, brake
normally but do not pump your brakes. If you do,
the pedal may get harder to push down. If your engine
stops, you will still have some power brake assist.
But you will use it when you brake. Once the power
assist is used up, it may take longer to stop and
the brake pedal will be harder to push.
Anti-lock Brake System (ABS)
Your vehicle may have anti-lock brakes. ABS is an
advanced electronic braking system that will help
prevent a braking skid.
If your vehicle has anti-lock
brakes, this warning light
on the instrument panel will
come on briey when
you start your vehicle.
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Remember: Anti-lock does not change the time you
need to get your foot up to the brake pedal or always
decrease stopping distance. If you get too close to
the vehicle in front of you, you will not have time to apply
your brakes if that vehicle suddenly slows or stops.
Always leave enough room up ahead to stop, even
though you have anti-lock brakes.
Using Anti-Lock
Do not pump the brakes. Just hold the brake pedal
down rmly and let anti-lock work for you. You may feel
a slight brake pedal pulsation or notice some noise,
but this is normal.
Braking in Emergencies
At some time, nearly every driver gets into a situation
that requires hard braking.
If you have anti-lock, you can steer and brake at the
same time. However, if you do not have anti-lock, your
rst reaction — to hit the brake pedal hard and hold
it down — may be the wrong thing to do. Your wheels
can stop rolling. Once they do, the vehicle can not
respond to your steering. Momentum will carry it
in whatever direction it was headed when the wheels
stopped rolling. That could be off the road, into the very
thing you were trying to avoid, or into traffic.If you do not have anti-lock, use a “squeeze” braking
technique. This will give you maximum braking
while maintaining steering control. You can do this by
pushing on the brake pedal with steadily increasing
pressure.
In an emergency, you will probably want to squeeze the
brakes hard without locking the wheels. If you hear or
feel the wheels sliding, ease off the brake pedal.
This will help you retain steering control. If youdohave
anti-lock, it is different. See “Anti-Lock Brake System”
in this section.
In many emergencies, steering can help you more than
even the very best braking.Traction Control System (TCS)
(3800 V6 Engine)
Your vehicle may have a traction control system that
limits wheel spin. This is especially useful in slippery road
conditions. The system operates only if it senses that one
or both of the front wheels are spinning or beginning to
lose traction. When this happens, the system reduces
engine power and may also upshift the transaxle and
apply the front brakes to limit wheel spin.
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