2004 CADILLAC CTS V service

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 doesn’t
release fully. If it stays on after your parking brake is
fully released, it means you have a brake problem.
If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
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 4-32.
{CAUTION:
Your brake system may not be working
properly if the brake system warning light is
on. Driving with the brake system warning light
on can lead to an accident. If the light is still
on after you have pulled off the road and
stopped carefully, have the vehicle towed
for service.
Anti-Lock Brake System
Warning Light
With the anti-lock brake
system, the light will come
on when your engine is
started and may stay on
for several seconds.
That’s normal.
If the ABS warning light comes on and stays on, there
may be a problem with the anti-lock portion of the brake
system. If the red BRAKE light is not on, you
still have brakes, but you don’t have antilock brakes.
SeeBrake System Warning Light on page 3-43.
If the light stays on, turn the ignition to OFF. If the light
comes on when you’re driving, stop as soon as possible
and turn the ignition off. Then start the engine again to
reset the system. If the light still stays on, or comes on
again while you’re driving, your vehicle needs service.
If the regular brake system warning light isn’t on, you still
have brakes, but you don’t have anti-lock brakes. If the
regular brake system warning light is also on, you don’t
have anti-lock brakes and there’s a problem with your
regular brakes. SeeBrake System Warning Light on
page 3-43.
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Traction Control System (TCS)
Warning Light
If the TC (traction control)
warning light comes on
and stays on, there may be
a problem with the
traction control system.
The TC (traction control) warning light will come on
briey when you turn the ignition to ON. If it doesn’t
come on then, have it xed so it will be ready to warn
you if there is a problem.
The light will also come on if you turn the traction control
system off using the TC (traction control) on/off button
located in the glove box for the CTS and on the steering
wheel for the CTS-V.
If the TC (traction control) warning light stays on or
comes on while you are driving, pull off the road as soon
as possible and stop carefully. Try resetting the system
by turning the ignition off then back on. If the light still
stays on or comes back on again while you are driving,
your vehicle needs service. Have the traction control
system inspected as soon as possible. SeeTraction
Control System (TCS) (CTS) on page 4-8orTraction
Control System (TCS) (CTS-V) on page 4-9for
more information.
Engine Coolant Temperature
Warning Light (CTS)
This light tells you that
your engine is very hot.
This light will come on when you rst start the vehicle
as a check to let you know that the light is working. It will
go out after a few seconds. If the light does not come
on, the bulb may be burned out. See your dealer
for assistance in changing the bulb.
If the light does not go out or if the light comes on and
stays on while you are driving, your vehicle may
have a problem with the cooling system. You should
stop the vehicle and turn off the engine as soon
as possible to avoid damage to the engine. A warning
chime will sound when this light is on, also.
SeeEngine Overheating on page 5-31and
Message Center (CTS-V) on page 3-53(CTS-V)
for more information.
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Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with 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 notbe 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,
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 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.
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 Your Tank on page 5-7. 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.
SeeGasoline 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 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.
This light tells you if there
could be a problem with
your engine oil pressure.
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The light goes on when you turn your key to ON or
START. It goes off once you start your engine. That’s a
check to be sure the light works. If it doesn’t 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 isn’t owing through your engine properly.
You could be low on oil and you might have some
other system problem. SeeEngine Oil on page 5-18
for more information.
Winter Driving Mode Light
(Automatic Transmission)
This light will come on
when the winter driving
mode feature is in use.
When you turn off the winter driving mode feature, the
light will go out. If it stays on, your vehicle may need
service. See your dealer. See “Winter Driving Mode”
underAutomatic Transmission Operation on page 2-26
for more information.
Sport Mode Light
(Automatic Transmission)
This light will come on
while the sport mode
is in use.
When you turn off the sport mode, the light will
go out. If it stays on, your vehicle may need service.
See your dealer. See “Sport Mode” under
Automatic Transmission Operation on page 2-26
for more information.
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Transmission Fluid Hot Message
When you see this ashing
symbol, the transmission
uid temperature is
high (290°F (143°C)).
To acknowledge this warning, press either button on the
outboard switch on the left spoke of the steering wheel.
After you press this button, the warning will redisplay
every 10 minutes until the temperature returns to the
normal operating range. If this message appears, you
may continue to drive at a slower speed while monitoring
the transmission uid temperature. Ideally, the
transmission oil temperature should not rise above
265°F (129°C). If you regularly experience temperatures
above this limit due to high performance operation, it is
recommended to use an auxiliary uid cooler for the
transmission and differential. See your Cadillac dealer for
details. If this warning is displayed during normal vehicle
operation on at roads, your vehicle may need service.
See your dealer for an inspection. SeeDIC Warnings and
Messages on page 3-70andManual Transmission Fluid
on page 5-27for more information.
Hot Coolant Temperature
Warning Message
When you see this ashing
symbol, the engine coolant
temperature is high
(257°F (125°C)).
To acknowledge this warning, press either button on the
outboard switch on the left spoke of the steering
wheel. After you press a button, this warning will
redisplay every 10 minutes until the temperature returns
to the normal operating range. Driving aggressively
or driving on long hills can cause the engine coolant
temperature to be higher than normal. Display of
this warning should correspond with the Engine Coolant
Temperature Warning Light. SeeEngine Coolant
Temperature Warning Light (CTS) on page 3-45for
more information. If this warning is displayed during
normal vehicle operation on at roads, your vehicle may
need service. See your dealer for an inspection.
3-57

Check Engine Oil Pressure Message
When you see this ashing
symbol, the engine oil
pressure is low.
To acknowledge this warning, press either button on the
outboard switch on the left spoke of the steering
wheel. After you press this button, the warning will
redisplay every 10 minutes until the pressure returns to
the normal operating range. Oil pressure should be
20 to 80 psi (140 to 550 kPa). In certain situations such
as long, extended idles on hot days, it could read as
low as 6 psi (40 kPa) and still be considered normal.
It may vary with engine speed, outside temperature and
oil viscosity. This warning should correspond with the
Oil Pressure Light. SeeOil Pressure Light on page 3-49
for more information.
Oil Temperature Warning Message
When you see this ashing
symbol, the engine oil
temperature is high.
To acknowledge this warning press either button on the
outboard switch on the left spoke of the steering
wheel. After you press a button, the warning will
redisplay every 10 minutes until the temperature returns
to the normal operating range. Driving aggressively
or driving on long hills can cause the engine oil
temperature to be higher than normal. If this warning is
displayed during normal vehicle operation on at
roads, your vehicle may need service. See your
GM dealer for an inspection. SeeEngine Oil on
page 5-18for more information.
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