2006 CADILLAC DTS engine

Malfunction Indicator Lamp
Check Engine Light
Your vehicle has 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 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 awhile, 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:Modications 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.
Modications 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. SeeAccessories
and Modifications on page 5-3.
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 Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and may damage the emission control system
on your vehicle. Diagnosis and service may
be required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
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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 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 the Tank on page 5-8. The
diagnostic system can determine if the fuel cap hasbeen 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 5-5. 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.
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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 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:
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:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be covered
by your warranty. Always follow the maintenance
schedule in this manual for changing engine oil.
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This light tells you if there
could be a problem with
your engine oil pressure.
This light will come on briey when you start your
engine. That is a check to be sure the light works. If it
does not 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
is not owing through your engine properly. You
could be low on oil and you might have some other
system problem.
Security Light
For information regarding
this light, see
Theft-Deterrent Systems
on page 2-19.
Fog Lamp Light
The fog lamps light will
come on when the fog
lamps are in use.
The light will go out when the fog lamps are turned off.
SeeFog Lamps on page 3-35for more information.
Rear Fog Lamp Light
This light will come on
when the rear fog lamps
are in use. For more
information seeFog Lamps
on page 3-35.
Canada Only
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Lights On Reminder
This light comes on
whenever the parking
lamps are on.
SeeHeadlamps on Reminder on page 3-34for more
information.
Cruise Control Light
This light comes on
whenever you set your
cruise control.
The light will go out when the cruise control is turned
off. SeeCruise Control on page 3-16andAdaptive
Cruise Control on page 3-19for more information.
Highbeam On Light
This light comes on
whenever the high-beam
headlamps are on.
SeeHeadlamp High/Low-Beam Changer on page 3-9
for more information.
Fuel Gage
The fuel gage shows
approximately how much
fuel is in the tank. It
works only when the
engine is on.
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If the fuel supply gets low, the Fuel Level Low message
will appear on the DIC and a single chime will sound.
Here are a few concerns some owners have had about
the fuel gage. All of these situations are normal and
do not indicate that anything is wrong with the fuel gage:
At the gas station the gas pump shuts off before
the gage reads full.
The gage may change when you turn, stop quickly
or accelerate quickly.
It takes a little more or less fuel to ll the tank than
the gage indicated. For example, the gage may have
indicated that the tank was half full, but it actually
took a little more or less than half the tank’s capacity
to ll the tank.
Driver Information Center (DIC)
The Driver Information Center (DIC) gives you the
status of many of your vehicle’s systems. The DIC
is also used to display warning/status messages. All
messages will appear in the DIC display located at
the bottom of the instrument panel cluster, below the
tachometer and speedometer. The DIC buttons are
located on the instrument panel, to the left of the
steering wheel.
The DIC comes on when the ignition is on. After a short
delay, the DIC will display the information that was
last displayed before the engine was turned off.
The top line of the DIC display shows the vehicle system
information and the warning/status messages. The
bottom line of the DIC display shows the odometer on
the left side. The bottom line of the DIC display also
shows a digital speedometer on the right side.
If a problem is detected, a warning message will appear
on the display. Be sure to take any message that
appears on the display seriously and remember that
clearing the message will only make the message
disappear, not correct the problem.
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AVERAGE SPEED
This display shows the average speed of the vehicle in
either miles per hour (mph) or kilometers per hour (km/h).
This average is calculated based on the various vehicle
speeds recorded since the last reset of this display. To
reset this display, press the set/reset button. The display
will return to zero.
BATTERY VOLTAGE
This display shows the current battery voltage. If the
voltage is in the normal range, the value will display. For
example, the display may read BATTERY VOLTAGE
13.2 VOLTS. If the voltage is low, the display will show
LOW. If the voltage is high, the display will show HIGH.
Your vehicle’s charging system regulates voltage based
on the state of the battery. The battery voltage may
uctuate when viewing this information on the DIC. This
is normal. SeeCharging System Light on page 3-61for
more information.
If there is a problem with the battery charging system,
the DIC will display a message. SeeDIC Warnings
and Messages on page 3-76for more information.
Blank Display
This display shows no information.
Vehicle Information Display Menu Items
T
(Vehicle Information):The following display
menu items can be displayed by pressing the vehicle
information button:
OIL LIFE REMAINING
If the vehicle has this display, it shows the estimated oil
life remaining. If you see 99% OIL LIFE REMAINING on
the display, that means that 99% of the current oil life
remains.
When the oil life is depleted, the CHANGE ENGINE OIL
SOON message will appear on the display. You should
change your oil as soon as possible. In addition to the
engine oil life system monitoring the oil life, additional
maintenance is recommended in the Maintenance
Schedule in this manual. SeeScheduled Maintenance
on page 6-4andEngine Oil on page 5-13.
Remember, you must reset the OIL LIFE yourself
after each oil change. It will not reset itself. Also, be
careful not to reset the OIL LIFE accidentally at any
time other than when the oil has just been changed.
It cannot be reset accurately until the next oil change.
To reset the engine oil life system, SeeEngine Oil
Life System on page 5-16. The display will show 100%
when the system is reset.
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CHANGE ENGINE OIL SOON
When this message displays, it means that service is
required for your vehicle. See your GM dealer. See
Engine Oil on page 5-13andScheduled Maintenance
on page 6-4for more information.
When you reset the CHANGE ENGINE OIL SOON
message by clearing it from the display, you still must
reset the engine oil life system separately. For more
information on resetting the engine oil life system, see
Engine Oil Life System on page 5-16.
CHECK TIRE PRESSURE
This symbol appears with
this message.
If your vehicle has a Tire Pressure Monitor (TPM)
system, this message will display when the tire pressure
in one of the tires needs to be checked. This message
will also display LEFT FRONT, RIGHT FRONT,
LEFT REAR, or RIGHT REAR to indicate which tire
needs to be checked.You can receive more than one tire pressure message
at a time. To read the other messages that may
have been sent at the same time, press the set/reset
button. If a tire pressure message appears on the DIC,
stop as soon as you can. Have the tire pressures
checked and set to those shown on your Tire Loading
Information Label. SeeTires on page 5-49,Loading
Your Vehicle on page 4-31, andInation - Tire Pressure
on page 5-56. The DIC display also shows the tire
pressure values for the front and rear tires by pressing
the vehicle information button. SeeDIC Controls
and Displays on page 3-72. If the tire pressure is low,
the low tire pressure warning light will come on. SeeLow
Tire Pressure Warning Light on page 3-63.
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