2003 CADILLAC DEVILLE light

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.
Charging System Light
When you turn the key to
ON or START, this light
will come on brie¯y
to show that the generator
and battery charging
systems are working
properly.
If this light stays on, you need service and you should
take your vehicle to the dealer at once. To save
your battery until you get there, turn off all accessories.
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Brake System Warning and Parking
Brake Indicator 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.
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 fully
release. If it stays on after your parking brake is
fully released, it means you have a brake problem.
{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.
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. See
Towing
Your Vehicle on page 4-31.
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Anti-Lock Brake System Warning
Light
With the anti-lock brake
system, the light(s) will
come on when your engine
is started and may stay
on for several seconds.
That's normal.
If the light stays on, turn the ignition to OFF. Or, if the
light comes 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, your vehicle
needs service. If the regular brake system warning
light isn't on, you still have brakes, but you don't have
anti-lock brakes. If the regular brake system warning
light is also on, you don't have anti-lock brakes
and there's a problem with your regular brakes. See
Brake System Warning and Parking Brake Indicator
Light on page 3-47.
The anti-lock brake system warning light should come
on brie¯y 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.
Traction Control System (TCS)
Warning Light
This warning light should come on brie¯y when the
engine is started.
If the warning light doesn't come on then, have it ®xed
so it will be ready to warn you if there's a problem.
If it stays on, or comes on when you're driving, there
may be a problem with your traction control system and
your vehicle may need service. When this warning
light is on, the system will not limit wheel spin. Adjust
your driving accordingly.
United StatesCanada (Analog Only)
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The traction control system warning light may come on
for the following reasons:
·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 the traction control system is affected by an
engine-related problem, the system will turn off and
the warning light will come on.
·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.
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 5-27.
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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 5-27.
.
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. United States (Analog
Only)
Canada (Analog Only)
Digital Cluster
United StatesCanada
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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.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 emissio 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.
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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 5-7. 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 5-4. 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.
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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.
Oil Pressure Light
{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.
This light tells you if there
could be a problem with
your engine oil pressure.
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