2003 CADILLAC DEVILLE engine

y9z(Fan):Pressing this switch cancels automatic
operation and places the system in manual mode.
Press this switch to increase or decrease the fan speed.
Press the MODE switch until AUTO is displayed to
return to automatic operation.
yTEMPz(Temperature):Press this switch to
increase or decrease the temperature for the rear seat
passengers.
For cool air to be sent to the rear of the vehicle, the
air-conditioning system on the main climate-control
panel must be on. If it is not on, then the temperature in
the rear of the vehicle will remain at cabin temperature.
Be sure to keep the area under the front seats clear
of any objects so that the air inside of your vehicle can
circulate effectively.
Passenger Compartment Air Filter
The passenger compartment air ®lter traps most of the
pollen from the air entering your vehicle. Like your
vehicle's engine air cleaner/®lter, it may need to
be changed periodically. For how often to change the
passenger compartment air ®lter, see
Part A: Scheduled
Maintenance Services on page 6-4.
The access panel for the passenger compartment air
®lter is located under the hood near the windshield,
on the passenger's side of the vehicle.
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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 3-57for
more information.
Instrument Panel Cluster
The instrument panel cluster is designed to let you
know at a glance how your vehicle is running. You'll
know how fast you're going, how much fuel you're using
and many of the other things you'll need to know to
drive safely and economically.
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English/Metric Button
By pressing this button
located to the left of the
steering wheel on the
instrument panel, you can
go back and forth from
English (miles) to
metric (kilometers).
Other readings such as temperature, fuel and trip
odometer also go back and forth between English
and metric.
Vehicle Speed Limiter
This feature prevents your vehicle from exceeding
speeds that the tires are not rated for. When this
happens, the engine's fuel supply is shut off. When the
vehicle speed slows, the fuel supply will come on again.
Tachometer (Analog Cluster Only)
This gage indicates the
engine speed in revolutions
per minute (rpm).
Notice:Do not operate the engine with the
tachometer in the shaded warning area, or engine
damage may occur.
Engine Speed Limiter
This feature prevents the engine from operating at too
many revolutions per minute (rpm). When the engine's
rpm are critically high, the fuel supply to the engine
is shut off. When the engine speed slows, the fuel
supply will come on again. This helps prevent damage
to the engine.
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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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