2003 CADILLAC SEVILLE check engine light

When trying to start the
vehicle, if the engine does
not start and the
SECURITY light comes on,
the key may have a
damaged transponder.
Turn the ignition off and
try again.
If the engine does not start, and the key appears to be
undamaged, try another ignition key. At this time,
you may also want to check the fuse. See
Fuses and
Circuit Breakers on page 5-93. If the engine still
does not start with the other key, your vehicle needs
service. If your vehicle does start, the ®rst key may be
faulty. See your dealer who can service the PASS-Key
ž
III to have a new key made.It is possible for the PASS-Key
žIII decoder to learn the
transponder value of a new or replacement key. Up
to 10 additional keys may be programmed for the
vehicle. This procedure is for learning additional
keys only.
Canadian Owners:If you lose or damage your keys,
only a GM dealer can service PASS-Key
žIII to
have new keys made. To program additional keys you
will require two current driver's keys (black in color). You
must add a step to the following procedure. After
Step 2, repeat Steps 1 and 2 with the second current
driver's key. Then continue with Step 3.
To program the new key do the following:
1. Verify that the new key has PK3 stamped on it.
2. Insert the current driver's key in the ignition
and start the engine. If the engine will not start see
your dealer for service.
3. After the engine has started, turn the key to OFF,
and remove the key.
4. Insert the key to be programmed and turn it to ON
within 10 seconds of removing the previous key.
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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 brie¯y 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. 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 also has a Driver Information Center (DIC)
that works along with the warning lights and gages.
See
Driver Information Center (DIC) on page 3-53for
more information.
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Engine Coolant Temperature
Warning Light
This light tells you that
your engine has
overheated. As a check,
the light should come
on for a few seconds when
you start your engine.
If this light comes on and stays on, you should
stop your vehicle and turn the engine off as soon as
possible. A warning chime should also sound if this light
comes on.
See
Engine Overheating on page 5-28.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature. If the
gage pointer moves into the shaded area, the engine
is too hot.
That reading means the same thing as the warning
light ± the engine coolant has overheated. See
Engine
Overheating on page 5-28.
United StatesCanada
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Malfunction Indicator Lamp
Service Engine Soon Light in the
United States or Check Engine Light in
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 SERVICE ENGINE SOON or 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. United StatesCanada
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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 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.
·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 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 5-6. 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 5-4. 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.
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 in order to help
your vehicle pass an inspection:
Your vehicle will not pass this inspection if the SERVICE
ENGINE SOON or 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, your GM dealer can prepare the
vehicle for inspection.
3-49

Oil Pressure Light
{CAUTION:
Do not 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.This light tells you if there
could be a problem with
your engine oil pressure.
The light goes on when you turn your key to ON or
START. It goes off once you start your engine. That's a
check to be sure the light works. If it doesn't come
on, be sure to have it ®xed so it will be there to warn
you if something goes wrong.
When the light comes on and stays on, it means that oil
isn't ¯owing through your engine properly. You could
be low on oil and you might have some other system
problem.
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CHANGE ENGINE OIL ± 82:This means that the life
of the engine oil has expired and it should be changed
within 200 miles. After an oil change, the Oil Life
Indicator must be reset. See
Oil Life Indicator on
page 3-77. SeeEngine Oil on page 5-13.
CHANGE TRANS FLUID ± 47:This message will
appear when it is time to change the transaxle ¯uid. See
Part A: Scheduled Maintenance Services on page 6-4for the proper ¯uid and change intervals.
CHECK BRAKE FLUID ± 37:This message will
display if the ignition is in ON to inform the driver that
the brake ¯uid level is low. Have the brake system
serviced by a technician as soon as possible. See
Brake
System Warning and Parking Brake Indicator Light on
page 3-43
.
CHECK COOLANT LEVEL ± 2:This message will
appear when there is a low level of engine coolant. Have
the cooling system serviced by a technician as soon
as possible. See
Engine Coolant on page 5-25.CHECK FUEL GAGE ± 50:This message will appear
when the fuel supply is less than 5 gallons (18.9 L)
and the display is turned off. A single chime will also
sound when this message is displayed.
CHECK GAS CAP ± 61:This message will appear if
the gas cap has not been fully tightened. You should
recheck your gas cap to ensure that it's on properly.
CHECK OIL LEVEL ± 36:For correct operation of the
low oil sensing system, your vehicle should be on a
level surface. A false CHECK OIL LEVEL message may
appear if the vehicle is parked on a grade. The oil
level sensing system does not check for actual oil level
if the engine has been off for a short period of time,
and the oil level is never checked while the engine is
running. If the CHECK OIL LEVEL message appears,
and your vehicle has been parked on level ground
with the engine off for at least 30 minutes, the oil level
should be checked by observing the oil dipstick. Prior to
checking the oil level, be sure the engine has been
off for a few minutes and your vehicle is on a level
surface. Then check the dipstick and add oil if
necessary. See
Engine Oil on page 5-13.
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