2003 CADILLAC DEVILLE service

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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·AVG MPH (Average Miles per Hour):This
message shows the average speed you have
traveled at since the last time you reset the value.
To reset the value, press the INFO button to
display AVG MPH then press and hold the INFO
RESET button until 0.0 AVG MPH is displayed.
·TIMER:This feature is like a stopwatch, in that you
can clock the time it takes to get from one point to
another.
To operate, press the INFO button to display
TIMER. Each of the ®elds for the hours, minutes
and seconds are two numeric digits.
Once TIMER 00:00:00 is displayed, press the
ON/OFF button to start the timing feature. Press
the ON/OFF button again to stop it. If you will
be starting and stopping your vehicle, during a trip
for instance, the TIMER feature will automatically
start timing where it left off when you last stopped.
To reset it, press and hold the INFO RESET
button until the display reads TIMER 00:00:00.
Press the INFO button to exit from the TIMER
display.
·ENGINE OIL LIFE:Press the INFO button to
display ENGINE OIL LIFE, then press and hold the
INFO RESET button until 100% ENGINE OIL
LIFE is displayed. (This only needs to be reset after
you have had the oil changed.)
·TRANSMISSION FLUID LIFE:Under normal
conditions, the rate of deterioration of the
transmission ¯uid is slow. See
Part A: Scheduled
Maintenance Services on page 6-4for proper
¯uid and change intervals. To reset the transmission
¯uid life, press the INFO button to display TRANS
FLUID LIFE, then press and hold the INFO
RESET button until 100% TRANS FLUID LIFE is
displayed. (This only needs to be reset after
you have had the ¯uid changed.)
ON/OFF:Pressing this button turns the Programming
and Personalization Features on and off. (FEATURE
PROGRAMMING must be displayed on the DIC to begin
actual programming.) This button also starts and
stops the timer.
MILES RANGE:(Analog Cluster Only) This message
shows about how many miles you can drive without
re®lling your fuel tank. Once the range drops below
40 miles (64 km) remaining, the display will show LOW.
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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 3-79. 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 3-47
.
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 5-24.
CHECK FUEL GAGE ± 50:(Analog Cluster) 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.
CHECK TIRE PRESSURE ± 144:This message is
displayed when the Tire Pressure Monitor (TPM) system
detects a low or high tire pressure condition in one or
more of the road tires. By pressing the INFO button up or
down, the DIC display will show which tire or tires do not
have the correct in¯ation pressure. A ªLOW TIREº
condition exists when the tire's air pressure is under
25 psi (172 kPa) and a ªHIGH TIREº condition exists
when the tire's air pressure is above 38 psi (262 kPa).
The system will display the air pressure, the tire location
(LF, RF, RR or LR) and if the air pressure is low or high.
The tire pressure information is available in English or
metric measurements. For example, a driver's side front
tire that is low may be shown as: 22 PSI LF TIRE LOW.
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ENGINE COOLANT HOT, IDLE ENGINE ± 44:This
message will appear when the engine coolant
temperature is over 262ÉF (128ÉC). Stop and allow your
vehicle to idle in PARK (P) until it cools down and the
message is removed. Do not increase engine speed
above a normal idle. If it does not cool down, turn off the
engine and have it serviced before driving it again.
Severe engine damage can result from an overheated
engine. See
Engine Overheating on page 5-27.
ENGINE HOT±AC OFF ± 16:This message displays
when the engine coolant becomes hotter than the normal
operating temperature. To avoid added strain on a hot
engine, the air conditioning compressor is automatically
turned off. When the coolant temperature returns to
normal, the A/C operation will automatically resume. You
can continue to drive your vehicle. If this message
continues to appear, have the system repaired as soon
as possible to avoid compressor damage.
ENGINE OVERHEATED, STOP ENGINE ± 42:This
message will appear when the engine has overheated.
Stop and turn the engine off immediately to avoid severe
engine damage. See
Engine Overheating on page 5-27.
A multiple chime will also sound when this message is
displayed.
ENGINE POWER REDUCED ± 41:This message
informs you that the vehicle is reducing engine power
because the transaxle is being placed in gear under
conditions that may cause damage to the vehicle's
engine, transaxle or ability to accelerate.FUEL LEVEL LOW ± 11:This message serves as a
warning that the fuel level in the tank is critically
low. Stop for fuel soon. A single chime will sound when
this message is displayed.
HEADLAMPS SUGGESTED ± 23:If it's dark enough
outside and the headlamps and Twilight Sentinel
ž
controls are off, this message will display on the DIC.
This message informs the driver that turning on the
exterior lamps is recommended even though the DRL
are still illuminated. It has become dark enough outside
to require the headlamps and/or other exterior lamps.
This message will also appear if the optional
RainsenseŸ wiping feature is on and the Twilight
Sentinel
žis off.
ICE POSSIBLE ± 13:This message appears when the
outside air temperature is cold enough to create icy
road conditions.
LEFT REAR DOOR AJAR ± 142:The left rear door is
open or ajar when this message appears. The ignition
must be in ON and the transaxle not in PARK (P) for this
message to display. A chime will sound if the vehicle's
speed is greater than 3 mph (5 km/h).
OIL PRESSURE LOW STOP ENGINE ± 35:If this
message appears while the engine is running, stop the
engine and do not operate it until the cause of low oil
pressure is corrected. Severe damage to the engine can
result. A multiple chime will sound when this message is
displayed.
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PASSENGER DOOR AJAR ± 141:The right front
passenger's door is open or ajar when this message
appears. The ignition must be in ON and the transaxle
not in PARK (P) for this message to display. A chime
will sound if the vehicle's speed is greater than
3 mph (5 km/h).
RIGHT REAR DOOR AJAR ± 143:The right rear door
is open or ajar when this message appears. The
ignition must be in ON and the transaxle not in PARK (P)
for this message to display. A chime will sound if the
vehicle's speed is greater than 3 mph (5 km/h).
SERVICE AC SYSTEM ± 14:This message appears
when the electronic sensors that control the air
conditioning and heating systems are no longer working.
Have the climate control system serviced if you notice
a drop in heating and air conditioning efficiency.
SERVICE AIR BAG ± 83:There is a problem with the
air bag system when this message appears. Let
only a quali®ed technician work on your vehicle. Have
your vehicle serviced by your dealership immediately.
SERVICE CHARGING SYS ± 102:This message
will display when a problem with the charging system
has been detected. Have your vehicle serviced at
your dealership.SERVICE ELECTRICAL SYS ± 106:This message will
display if an electrical problem has occurred within
the Powertrain Control Module (PCM) or the ignition
switch. Have your vehicle serviced by your dealership.
SERVICE FUEL SYSTEM ± 101:The Powertrain
Control Module (PCM) has detected a problem within
the fuel system when this message appears. Have your
vehicle serviced by your dealership.
SERVICE IDLE CONTROL ± 107:A problem with the
idle control has occurred when this message displays.
Have your vehicle serviced by your dealership.
SERVICE STABILITY SYS ± 54:If you ever see the
SERVICE STABILITY SYS message, it means
there may be a problem with your stability enhancement
system. If you see this message, try to reset the
system (stop, turn off the engine, then start the engine
again). If the SERVICE STABILITY SYS message
still comes on, it means there is a problem. You should
see your dealer for service. Reduce your speed and
drive accordingly. A single chime will also sound when
this message is displayed.
SERVICE STEERING ± 127:This message is displayed
when a problem has been detected in the magnetic
speed variable assist steering system. If message
comes on, service is required.
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SERVICE SUSPENSION SYS ± 84:This message is
displayed to indicate that the suspension system is
not operating properly. To correct this problem, have
your vehicle serviced at your dealership.
SERVICE THEFT SYSTEM ± 34:This message means
there is a problem with the PASS-Key
žIII system. A
fault has been detected in the system which means that
the system is disabled and is not protecting the
vehicle. The vehicle usually restarts, however, you may
want to take your vehicle to your dealer before turning
off the engine.
SERVICE TPM SYSTEM ± 51:When this message is
displayed, the Tire Pressure Monitor (TPM) system
is not working properly. See your dealer for service.
SERVICE TRANSMISSION ± 100:See your dealer for
repair.
SERVICE VEHICLE SOON ± 3:This message is
displayed when a non-emissions related powertrain
malfunction occurs. Have your vehicle serviced by
a technician as soon as possible.
SPEED LIMIT TO 90 ± 113:A failure in the suspension
control system has occurred when this message
appears. The Powertrain Control Module (PCM)
determines the speed to which your vehicle is limited.
Have your vehicle serviced if this message appears.STABILITY SYS ENGAGED ± 55:You may see the
STABILITY SYS ENGAGED message on the Driver
Information Center. It means that an advanced,
computer-controlled system has come on to help your
vehicle continue to go in the direction in which you're
steering. This stability enhancement system activates
when the computer senses that your vehicle is just
starting to spin, as it might if you hit a patch of ice or
other slippery spot on the road. When the system is on,
you may hear a noise or feel a vibration in the brake
pedal. This is normal.
When the STABILITY SYS ENGAGED message is on,
you should continue to steer in the direction you want to
go. The system is designed to help you in bad weather or
other difficult driving situations by making the most of
whatever road conditions will permit. If the STABILITY
SYS ENGAGED message comes on, you'll know that
something has caused your vehicle to start to spin, so
you should consider slowing down. A single chime will
also sound when this message is displayed.
STARTING DISABLED REMOVE KEY ± 33:This
message will appear when the PASS-Key
žIII system
detects that an improper ignition key is being used to try
to start the vehicle. Check the ignition key for damage.
If it is damaged, it may need to be replaced. If it is
not damaged, remove the key and try to start the vehicle
again. If it still does not start, try another ignition key
or see your dealer for service.
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