2006 CADILLAC STS engine

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.
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 4-37.
{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. United StatesCanada
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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 is normal.
If the ABS warning light comes on and stays on, there
may be a problem with the antilock portion of the
brake system. If the red BRAKE light is not on, you still
have brakes, but you do not have antilock brakes.
SeeBrake System Warning Light on page 3-64.
If the light stays on, press the ignition button to OFF/ACC.
If the light comes on when you are 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 are driving, your vehicle needs
service. If the regular brake system warning light is not
on, you still have brakes, but you do not have anti-lock
brakes. If the regular brake system warning light is also
on, you do not have anti-lock brakes and there is a
problem with your regular brakes. SeeBrake System
Warning Light on page 3-64.The anti-lock brake system warning light should come
on briey when you turn the ignition on. If the light does
not come on then, have it xed so it will be ready to
warn you if there is a problem.
Low Tire Pressure Warning Light
This light will come on
briey as you start the
engine, for vehicles
equipped with the Tire
Pressure Monitor System.
It will then come on only when a at or low tire pressure
condition exists.
SeeTire Pressure Monitor System on page 5-66for
more information.
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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 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.
The light will also come on if you turn the traction
control system off using the TC (traction control) on/off
button located on the console.
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. Turn your engine off and then
restart it. 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) on page 4-9and
StabiliTrak
®System on page 4-11for more information.
Also seeCompetitive Driving Mode (STS-V) on
page 4-10for more information.
Engine Coolant Temperature
Warning Light
The engine coolant
temperature warning light
will come on when the
engine is very hot.
This light will also come 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 your vehicle to overheat, seeOverheated
Engine Protection Operating Mode on page 5-31.
SeeEngine Overheating on page 5-30andDIC
Warnings and Messages on page 3-79for more
information.
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Engine Coolant Temperature Gage
This gage shows the
engine coolant
temperature.
It can be used to see when your engine has warmed up
and to make sure your 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 5-30for more information.
Malfunction Indicator Lamp
Check Engine Light
Your vehicle has 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 not
be as good, and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.
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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. SeeAccessories
and Modifications on page 5-3.
This light should come on briey, as a check to show
you it is working, as you start the engine. 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.
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 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 engine 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.
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If the Light Is On Steady
You also 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 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 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. See
Gasoline 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.
To perform a Check Engine light bulb check with the
keyless ignition, make sure the transmitter fob is in the
passenger compartment. SeeIgnition Positions on
page 2-24. Press the bottom of the ACC button on
the instrument panel and hold the button down for
ve seconds. The instrument panel, including the Check
Engine light, will light up and the ignition will be on, but
the engine will not start — if you press the bottom of the
ACC button only briey, less than ve seconds, the
accessory power mode will be turned on, but not the
ignition. After the bulb check, be sure to press and
release the ACC button again to turn the ignition off
and avoid draining the vehicle’s battery.
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.
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If equipped, this light tells
you if there could be a
problem with your engine
oil pressure.
This light will come on briey when you start your
engine. That is a check to be sure the light works. If it
does not 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
is not owing through your engine properly. You
could be low on oil and you might have some other
system problem.
Security Light
For information regarding
this light, see
Theft-Deterrent System on
page 2-21.
Fog Lamp Light
The fog lamps light will
come on when the fog
lamps are in use.
The light will go out when the fog lamps are turned off.
SeeFog Lamps on page 3-37for more information.
Lights On Reminder
This light comes on
whenever the parking
lamps are on.
SeeHeadlamps on Reminder on page 3-35for more
information.
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