2008 CADILLAC DTS check engine light

Remote Vehicle Start
The remote vehicle starting feature allows you to start
the engine from outside of the vehicle. It also starts up the
vehicle’s automatic climate control system. When the
remote start system is active, the climate control system
will heat and cool the inside of the vehicle according to
the previous settings of the system before turning the
vehicle off. The rear window defogger will be turned on by
the climate control system when it is cold outside. If the
vehicle has heated seats, they will also turn on when it is
cold outside. SeeHeated and Cooled Seats on page 1-3
for additional information. Cooled seats are not activated
during a remote start. Normal operation of the climate
control system will return after the key is turned to
ON/RUN. SeeDual Climate Control System on
page 3-42.
Laws in some communities may restrict the use of
remote starters. For example, some laws may require a
person using remote start to have the vehicle in view
when doing so. Check local regulations for any
requirements on remote starting of vehicles.
Do not use the remote start feature if your vehicle is low
on fuel. Your vehicle may run out of fuel.
If your vehicle has the remote start feature, the RKE
transmitter functions will have an increased range
of operation. However, the range may be less while the
vehicle is running.There are other conditions which can affect the
performance of the transmitter, seeRemote Keyless
Entry (RKE) System Operation on page 2-5for
additional information.
/(Remote Start):This button will be on the RKE
transmitter if you have remote start.
To start the vehicle using the remote start feature:
1. Aim the transmitter at the vehicle.
2. Press and release the transmitter’s lock button, then
immediately press and hold the transmitter’s remote
start button until the turn signal lights ash or if the
vehicle’s lights are not visible, press and hold the
remote start button for at least four seconds. The
vehicle’s doors will lock. Pressing the remote start
button again after the vehicle has started will turn off
the ignition.
When the vehicle starts, the parking lamps will turn
on and remain on while the vehicle is running.
3. If it is the rst remote start since the vehicle has been
driven, repeat these steps, while the engine is still
running, to extend the engine running time by
10 minutes. Remote start can be extended one time.
After entering the vehicle during a remote start, insert
and turn the key to ON/RUN to drive the vehicle.
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PASS-Key®III+ Electronic
Immobilizer Operation
Your vehicle has PASS-Key®III+ (Personalized
Automotive Security System) theft-deterrent system.
PASS-Key
®III+ is a passive theft-deterrent system.
The system is automatically armed when the key
is removed from the ignition.
The system is automatically disarmed when the key is
turned to ON/RUN, ACC/ACCESSORY or START
from the LOCK/OFF position.
You do not have to manually arm or disarm the system.
The security light will come on if there is a problem
with arming or disarming the theft-deterrent system.
When the PASS-Key
®III+ system senses that someone
is using the wrong key, it prevents the vehicle from
starting. Anyone using a trial-and-error method to start
the vehicle will be discouraged because of the high
number of electrical key codes.
If the engine does not start and the security light comes
on when trying to start the vehicle, there may be a
problem with your theft-deterrent system. Turn
the ignition off and try again.If the engine still 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, seeFuses
and Circuit Breakers on page 5-101. 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/retailer who can service the
PASS-Key
®III+ to have a new key made. In an
emergency, contact Roadside Assistance.
It is possible for the PASS-Key
®III+ decoder to “learn”
the transponder value of a new or replacement key. Up to
nine additional keys may be programmed for the vehicle.
The following procedure is for programming additional
keys only. If all the currently programmed keys are lost or
do not operate, you must see your dealer/retailer or a
locksmith who can service PASS-Key
®III+ to have keys
made and programmed to the system.
See your dealer/retailer or a locksmith who can service
PASS-Key
®III+ to get a new key blank that is cut
exactly as the ignition key that operates the system.
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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 briey when you start the
engine just to let you know they are 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 is 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 are a big help.
Your vehicle also has a Driver Information Center (DIC)
that works along with the warning lights and gages.
SeeDriver Information Center (DIC) on page 3-70for
more information.
3-53

Airbag Readiness Light
There is an airbag readiness light on the instrument
panel cluster, which shows the airbag symbol. The
system checks the airbag’s electrical system for
malfunctions. The light tells you if there is an electrical
problem. The system check includes the airbag
sensor, the pretensioners, the airbag modules, the
wiring and the crash sensing and diagnostic module.
For more information on the airbag system, seeAirbag
System on page 1-53.
This light will come on
when you start your
vehicle, and it will ash
for a few seconds.
The light should go out
and the system is ready.
If the airbag readiness light stays on after you start
the vehicle or comes on when you are driving,
your airbag system may not work properly.
Have your vehicle serviced right away.{CAUTION:
If the airbag readiness light stays on after you
start your vehicle, it means the airbag system
may not be working properly. The airbags in
your vehicle may not inate in a crash, or they
could even inate without a crash. To help
avoid injury to yourself or others, have your
vehicle serviced right away.
The airbag readiness light should ash for a
few seconds when you start the engine. If the light does
not come on then, have it xed immediately. If there
is a problem with the airbag system, an airbag Driver
Information Center (DIC) message may also come
on. SeeDIC Warnings and Messages on page 3-75for
more information.
3-57

Charging System Light
This light will come on
briey when you turn on
the ignition key, but
the engine is not running,
as a check to show
you it is working.
It should go out once the engine is running. If it stays
on, or comes on while driving, there could be a problem
with the charging system. A charging system Driver
Information Center (DIC) message may also appear.
SeeDIC Warnings and Messages on page 3-75
for more information. This light could indicate that
there are problems with a generator drive belt, or that
there is an electrical problem. Have it checked right
away. If you must drive a short distance with the light on,
be certain to turn off all the accessories, such as the
radio and air conditioner.
Brake System Warning 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 briey when you turn the
engine on. If it does not come on then, have it xed so
it will be ready to warn you if there is 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 does
not release fully. If it stays on after your parking brake
is fully released, it means you have a brake problem.
United StatesCanada
3-60

Engine Coolant Temperature Gage
This gage shows the
engine coolant
temperature.
It indicates when the engine has warmed up and if
the cooling system is operating properly. If the gage
pointer moves into the shaded area, the engine coolant
is too hot and the engine coolant temperature warning
light will come on. SeeEngine Overheating on
page 5-27for more information.
Tire Pressure Light
This light comes on briey
when the engine is started.
This light will also come on when one or more of your
tires are signicantly underinated.
A tire pressure message in the Driver Information
Center (DIC), may accompany the light. SeeDIC
Warnings and Messages on page 3-75for more
information.
Stop and check your tires as soon as it is safe to
do so. If underinated, inate to the proper pressure.
SeeTires on page 5-52for more information.
If a problem is detected with the Tire Pressure Monitor
System, this light will ash for approximately 60 seconds
and then stay on solid for the remainder of the ignition
cycle. SeeTire Pressure Monitor System on page 5-63
for more information.
3-64

Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation of
the fuel, ignition, and emission control systems. It makes
sure 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 an OBD II
problem and service
is required.
Malfunctions often are indicated by the system before
any problem is apparent. This can 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, the emission controls
might not work as well, your vehicle’s fuel economy
might not be as good, and the engine might not
run as smoothly. This could lead to costly repairs
that might not be covered by your warranty.Notice:Modications made to the engine,
transmission, 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 can cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This could
also result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 5-3.
This light comes on, as a check to show it is working,
when the ignition is turned ON/RUN but the engine is not
running. If the light does not come on, have it repaired.
This light also comes on during a malfunction in
one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions and
could damage the emission control system on your
vehicle. Diagnosis and service might be required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service might be required.
3-65

If the Light is Flashing
The following can prevent more serious damage to your
vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid 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 the vehicle.
Turn the ignition 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/retailer
for service as soon as possible.
If the Light Is On Steady
You might 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 has been left off or improperly installed.A loose or missing fuel cap allows 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 vehicle’s electrical system might be wet. The
condition is usually 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 causes
the engine not to run as efficiently as designed. You
might 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 might 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/retailer can check the vehicle. Your
dealer/retailer has the proper test equipment and
diagnostic tools to x any mechanical or electrical
problems that might have developed.
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