2009 CADILLAC DTS service

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 1-55.
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 3-73
for more information.
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Passenger Airbag Status Indicator
The vehicle has the passenger sensing system.
SeePassenger Sensing System on page 1-64for
important safety information. The overhead console
has a passenger airbag status indicator.
When the vehicle is started, the passenger airbag status
indicator will light ON and OFF, or the symbol for on
and off, for several seconds as a system check.
If you are using remote start to start the vehicle from a
distance, if equipped, you may not see the system check.
Then, after several more seconds, the status indicator
will light either ON or OFF, or either the on or off symbol,
to let you know the status of the right front passenger
frontal and seat-mounted side impact airbags.If the word ON or the on symbol is lit on the passenger
airbag status indicator, it means that the right front
passenger frontal airbag and seat-mounted side impact
airbag are enabled (may inate).
If the word OFF or the off symbol is lit on the passenger
airbag status indicator, it means that the passenger
sensing system has turned off the right front passenger
frontal and seat-mounted side impact airbag.
If, after several seconds, both status indicator lights
remain on, or if there are no lights at all, there may
be a problem with the lights or the passenger sensing
system. See your dealer/retailer for service.
{CAUTION:
If the airbag readiness light ever comes on and
stays on, it means that something may be wrong
with the airbag system. To help avoid injury to
yourself or others, have the vehicle serviced right
away. SeeAirbag Readiness Light on page 3-54
for more information, including important safety
information. United States
Canada
3-55

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 3-73for
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.
Brake System Warning Light
The vehicle’s hydraulic brake system is divided into two
parts. If one part is not working, the other part can still
work and stop the vehicle. For good braking both parts
need to be working.
If the warning light comes on, there is a brake problem.
Have the brake system inspected right away.
This light comes on briey when the engine is turned
on. If it does not come on then, have it xed so it will be
ready to warn if there is a problem.
United StatesCanada
3-56

When the ignition is on, the brake system warning
light also comes on when the parking brake is set.
The light will stay on if the parking brake does
not release fully. If it stays on after the parking brake
is fully released, it means there is a brake problem.
If the light comes on while driving, pull off the road
and stop carefully. The pedal may be harder to push,
or the pedal may go closer to the oor. It may take longer
to stop. If the light is still on, have the vehicle towed for
service. SeeTowing Your Vehicle on page 4-26.
{CAUTION:
The brake system might not be working properly if
the brake system warning light is on. Driving with
the brake system warning light on can lead to a
crash. If the light is still on after the vehicle has
been pulled off the road and carefully stopped,
have the vehicle towed for service.
Antilock Brake System (ABS)
Warning Light
For vehicles with
the Antilock Brake
System (ABS), this light
comes on briey when
the engine is started.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
If the ABS light stays on, turn the ignition off. If the
light comes on while driving, stop as soon as it is safely
possible and turn the ignition off. Then start the engine
again to reset the system. If the ABS light stays on, or
comes on again while driving, the vehicle needs service.
If the regular brake system warning light is not on, the
vehicle still has brakes, but not antilock brakes. If the
regular brake system warning light is also on, the vehicle
does not have antilock brakes and there is a problem with
the regular brakes. SeeBrake System Warning Light on
page 3-56.
For vehicles with a Driver Information Center (DIC),
seeDIC Warnings and Messages on page 3-73for
all brake related DIC messages.
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Traction Control System (TCS)
Warning Light
This warning light comes
on briey while starting the
engine.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light will then go off.
If it stays on, or comes on while driving, there may
be a problem with the traction control system and the
vehicle needs service. When this warning light is on,
the system will not limit wheel spin.
If the traction control system warning light comes on
and stays on when the system is turned on, the vehicle
needs service. SeeTraction Control System (TCS)
on page 4-6for more information.
StabiliTrak®Indicator Light
For vehicles with the
StabiliTrak®system, this
light comes on briey while
starting the engine.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
If the light comes on and stays on while driving, there
could be a problem with the StabiliTrak
®system and the
vehicle might need service. When this warning light is
on, the StabiliTrak
®system is off and does not limit
wheel spin.
The light ashes if the system is active and is working
to assist the driver with directional control of the
vehicle in difficult driving conditions.
SeeStabiliTrak
®System on page 4-6for more
information.
3-58

Lane Departure Warning (LDW)
Light
For vehicles with the lane
departure warning system,
this light briey comes
on amber, while starting
the vehicle, to indicate
that it is working.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
When driving at speeds of 35 mph (56 km) or greater
and LDW is turned on, a green warning symbol appears
when the system has detected lane markings on at
least one side of the vehicle.
For more information seeLane Departure Warning
(LDW) on page 2-49.When LDW is active, the amber warning symbol comes
on and ashes. Three beeps sound if a lane marking
is crossed without using the turn signal. If the warning
symbol is not on, LDW is not operating and will not
warn when the vehicle crosses a lane marking.
Engine Coolant Temperature
Warning Light
The engine coolant
temperature warning
light comes on when
the engine is very hot.
This light also comes on briey when the vehicle is
started.
If the light does not go out or comes on and stays on
while driving, there may be a problem with the cooling
system. Driving with engine coolant temperature light
on could cause the vehicle to overheat, seeOverheated
Engine Protection Operating Mode on page 5-30.
SeeEngine Overheating on page 5-28andDIC Warnings
and Messages on page 3-73for more information.
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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 3-73for 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 5-48for 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 5-60
for more information.
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 ensures 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,
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.
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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.This light 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 the vehicle. Diagnosis
and service might be required.
To prevent more serious damage to the vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
If towing a trailer, reduce the amount of cargo being
hauled as soon as it is possible.
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 key off, wait at least 10 seconds, and restart
the engine. If the light is still ashing, follow the previous
steps and see your dealer/retailer for service as soon
as possible.
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