2009 CADILLAC DTS engine

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.
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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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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 comes on. SeeEngine Overheating on page 5-28
for more information.
Tire Pressure Light
For vehicles with a tire
pressure monitoring
system, this light comes
on briey when the engine
is started.
It provides information about tire pressures and the
Tire Pressure Monitoring System.
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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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Light On Steady:An emission control system
malfunction has been detected on the vehicle.
Diagnosis and service might be required.
An emission system malfunction might be corrected by
doing the following:
Make sure the fuel cap is fully installed.
SeeFilling the 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 allows fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light off.
If the vehicle has been driven through a deep puddle
of water, the 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.
Make sure to fuel the vehicle with quality fuel.
Poor fuel quality causes the engine not to run as
efficiently as designed and can cause: stalling after
start-up, stalling when the vehicle is changed into
gear, misring, hesitation on acceleration, or
stumbling on acceleration. These conditions
might go away once the engine is warmed up.
If one or more of these conditions occurs, change the
fuel brand used. It will require at least one full tank of
the proper fuel to turn the light off.
SeeGasoline Octane on page 5-5.
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.
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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 ON/RUN and the light is not on.
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.
Oil Pressure Light
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches re.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice:Lack of proper engine oil maintenance
can damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow
the maintenance schedule in this manual for
changing engine oil.
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