2009 CADILLAC CTS check engine light

Immobilizer Operation (Key Access)
Your vehicle has a passive theft-deterrent system.
The system is automatically armed when the key
is removed from the ignition.
The theft-deterrent system is disarmed when the key is
turned to ON/RUN.
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.
The key uses a transponder that matches an immobilizer
control unit in your vehicle and automatically disarms the
system. Only the correct key will start the vehicle. If the
key is ever damaged, you may not be able to start your
vehicle.
When trying to start the vehicle, if the engine does not
start and the security light comes on, 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 5-115. 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 theft-deterrent system
and have a new key made.It is possible for the theft-deterrent system decoder to
learn the transponder value of a new or replacement key.
Up to 10 keys can be programmed for the vehicle.
The following procedure is for programming additional
keys only.
To program a new key do the following:
1. Verify that the new key has
1stamped on it.
2. Insert the current driver’s key in the ignition and
start the engine. If the engine will not start see
your dealer/retailer for service.
3. After the engine has started, turn the key to
LOCK/OFF, and remove the key.
4. Insert the key to be programmed and turn it to
ON/RUN within ve seconds of the ignition being
turned to LOCK/OFF in Step 3.
5. The security light will turn off once the key has
been programmed. It may not be apparent that
the security light went on due to how quickly the key
is programmed.
6. Repeat the Steps 1 through 4 if additional keys are
to be programmed.
In an emergency, contact Cadillac Roadside Service.
SeeRoadside Service on page 7-7.
Do not leave the key or device that disarms or
deactivates the theft deterrent system in the vehicle.
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Immobilizer Operation
(Keyless Access)
Your vehicle has a passive theft-deterrent system.
The system is automatically armed when the ignition
control knob is turned to LOCK/OFF.
The immobilization system is disarmed when the ignition
control knob is pushed in and a valid transmitter is
found in the vehicle.
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.
The system has one or more keyless access transmitters
that are matched to an immobilizer control unit in your
vehicle. Only a correctly matched keyless access
transmitter will start the vehicle. If the keyless access
transmitter is ever damaged, you may not be able to
start your vehicle.
When trying to start the vehicle, if the engine does not
start and the security light comes on, there may be a
problem with your immobilizer system. Turn the ignition
control knob off and try again.If the ignition control knob does not rotate, and the
keyless access transmitter appears to be undamaged,
try another keyless access transmitter. Or, you may
try placing the transmitter in the transmitter pocket
located in the center console. See “Electronic Key Not
Detected” underDIC Warnings and Messages on
page 3-58. At this time, you may also want to check the
fuse. SeeFuses and Circuit Breakers on page 5-115.
If the ignition control knob still does not rotate with
the other transmitter, your vehicle needs service. If the
ignition control knob does rotate, the rst transmitter
may be faulty. See your dealer/retailer who can service
the theft-deterrent system and have a new keyless
access transmitter programmed to the vehicle.
It is possible for the immobilizer system to learn new or
replacement keyless access transmitters. Up to 4 keyless
access transmitters can be programmed for the vehicle.
To program additional transmitters, see “Matching
transmitter(s) to Your Vehicle” underKeyless Access
System Operation on page 2-8.
Do not leave the key or device that disarms or
deactivates the theft deterrent system in the vehicle.
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To replace the passenger compartment air lter:
1. Turn the ignition to ON/RUN with the engine off.
2. Turn on the windshield wipers and turn the
ignition off again when the wipers are straight up
on the windshield.
This allows access to the leaf screen.
The passenger compartment air lter is located
under the screen.
3. Open the hood to access the engine compartment.
SeeHood Release on page 5-12for more
information.
4. Remove the three screws that hold the screen in
place and lift off the screen by lifting and sliding it
toward the center of the vehicle.
5. Pull out on the two tabs located on each end of the
lter cover.
6. Lift the lter cover off by pulling it straight up.
7. Remove the old lter and insert a new one.
SeeMaintenance Replacement Parts on page 6-16
for the correct part number for the lter.
8. Reverse Steps 1 through 6 to reinstall the cover.Warning Lights, Gages, and
Indicators
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
the warning lights and gages could prevent injury.
Warning lights come on when there may be or is a
problem with one of the vehicle’s functions. Some
warning lights come on briey when the engine is
started to indicate they are working.
Gages can indicate when there may be or is a problem
with one of the vehicle’s functions. Often gages and
warning lights work together to indicate a problem with
the vehicle.
When one of the warning lights comes on and stays on
while driving, or when one of the gages shows there
may be a problem, check the section that explains what
to do. Follow this manual’s advice. Waiting to do
repairs can be costly and even dangerous.
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Airbag Readiness Light
The system checks the airbag’s electrical system for
possible malfunctions. If the light stays on it indicates
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 1-58.
The airbag readiness light
ashes for a few seconds
when the engine is
started. If the light does
not come on then, have it
xed immediately.{CAUTION:
If the airbag readiness light stays on after the
vehicle is started or comes on while driving, it
means the airbag system might not be working
properly. The airbags in the vehicle might not
inate in a crash, or they could even inate
without a crash. To help avoid injury, have the
vehicle serviced right away.
If there is a problem with the airbag system, an airbag
Driver Information Center (DIC) message can also come
on. SeeDIC Warnings and Messages on page 3-58
for more information.
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Charging System Light
This light comes on briey
when the ignition key is
turned to START, but
the engine is not running,
as a check to show it
is working.
If it does not, have the vehicle serviced by your
dealer/retailer.
The light should go out once the engine starts. If it
stays on, or comes on while driving, there could be a
problem with the charging system. A charging system
message in the Driver Information Center (DIC) can also
appear. SeeDIC Warnings and Messages on page 3-58
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 the vehicle must be driven a short distance with
the light on, turn off accessories, such as the radio
and air conditioner.
Up-Shift Light
The vehicle may have an
up-shift light, it shows
when to shift to the next
higher gear for best
fuel economy.
SeeManual Transmission Operation on page 2-40
for more information.
For the CTS-V, the tracer lights function as a
performance up-shift light.
These tracers ash to indicate when to shift to the
next higher gear to avoid the engine speed limit.
SeeAutomatic Transmission Operation on page 2-36
orManual Transmission Operation on page 2-40
for more information.
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Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
If the engine coolant overheats the engine coolant
temperature warning light will come on. SeeEngine
Overheating on page 5-37andEngine Coolant
Temperature Warning Light on page 3-41for more
information.
Tire Pressure Light
For vehicles with a tire
pressure light, this light
comes on briey when the
engine is started and
provides information about
tire pressures and the
Tire Pressure Monitoring
System.
When the Light is On Steady
This indicates that one or more of the tires is signicantly
underinated.
A tire pressure message in the Driver Information Center
(DIC), can accompany the light. SeeDIC Warnings and
Messages on page 3-58for more information. Stop and
check the tires as soon as it is safe to do so. If a tire is
underinated, inate to the proper pressure. SeeTires on
page 5-61for more information.
When the Light Flashes First and Then is
On Steady
This indicates that there could be a problem with the
Tire Pressure Monitor System. The light ashes for
about a minute and stays on steady for the remainder
of the ignition cycle. This sequence repeats with
every ignition cycle. SeeTire Pressure Monitor System
on page 5-71for more information. United States
Canada
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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.
This light should come on
when the ignition is on, but
the engine is not running,
as a check to show it
is working.
If it does not come on, have the vehicle serviced by
your dealer/retailer.
If the check engine light comes on and stays on, while
the engine is running, this indicates that there is an
OBD II problem and service is required.Malfunctions often are indicated by the system before
any problem is apparent. Being aware of the light
can prevent more serious damage to the vehicle.
This system assists the service technician in correctly
diagnosing any malfunction.
Notice:If the vehicle is continually driven with
this light on, after a while, the emission controls
might not work as well, the 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 the vehicle warranty.
Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of the
vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect the vehicle’s emission
controls and can cause this light to come on.
Modications to these systems could lead to
costly repairs not covered by the vehicle warranty.
This could also result in a failure to pass a
required Emission Inspection/Maintenance test.
SeeAccessories and Modifications on page 5-3.
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If none of the above have made the light turn off, your
dealer/retailer can check the vehicle. The dealer/retailer
has the proper test equipment and diagnostic tools to
x any mechanical or electrical problems that might have
developed.
Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have or
might begin programs to inspect the emission control
equipment on the vehicle. Failure to pass this inspection
could prevent getting a vehicle registration.
Here are some things to know to help the vehicle pass
an inspection:
The vehicle will not pass this inspection if the check
engine light is on with the engine running, or if the
key is in the ON/RUN and the light is not on.
For vehicles with a Keyless Access ignition,
make sure the transmitter is in the passenger
compartment. SeeIgnition Positions (Key Access)
on page 2-31orIgnition Positions (Keyless Access)
on page 2-32.
The vehicle will not pass this inspection if the OBD II
(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 the battery has recently been replaced or if the
battery has run down. The diagnostic system is
designed to evaluate critical emission control
systems during normal driving. This can take several
days of routine driving. If this has been done and the
vehicle still does not pass the inspection for lack of
OBD II system readiness, your dealer/retailer can
prepare the vehicle for inspection.
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