2008 CADILLAC STS check engine

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 5-29for more information.
Tire Pressure Light
This light comes on briey
when the engine is started.
This light will also come on when one or more of your
tires are signicantly underinated.
A tire pressure message in the Driver Information Center
(DIC), may accompany the light. SeeDIC Warnings and
Messages on page 3-80for more information.
Stop and check your tires as soon as it is safe to
do so. If underinated, inate to the proper pressure.
SeeTires on page 5-57for more information.
If a problem is detected with the Tire Pressure Monitor
System, this light will ash for approximately 60 seconds
and then stay on solid for the remainder of the ignition
cycle. SeeTire Pressure Monitor System on page 5-68
for more information.
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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.
The check engine light
comes on to indicate
that there is an OBD II
problem and service
is required.
Malfunctions often are indicated by the system before
any problem is apparent. This can 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 a while, the emission controls
might not work as well, your 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 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 can cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your 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 briey, as a check to show it is
working, as you start the engine. If the light does not
come on, have it repaired. This light also 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 your vehicle. Diagnosis and service might
be required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service might be required.
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If the Light Is Flashing
The following can prevent more serious damage to
your vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid 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 the 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/retailer
for service as soon as possible.
If the Light Is On Steady
You might 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 5-7. 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.Did you just drive through a deep puddle of water?
If so, your 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.
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 causes
the engine not to run as efficiently as designed. You
might 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 might 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/retailer can check the vehicle. Your
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 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 2-28. 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 the battery or if the 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
dealer/retailer can prepare the vehicle for inspection.
Oil Pressure Light
Your vehicle may have
this feature.
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If the vehicle has an oil problem, this light may stay
on after the engine is started, or come on while you
are driving.
This light indicates that oil is not going through the engine
quickly enough to keep it lubricated. The engine could
be low on oil or could have some other oil problem.
Have it xed right away.
The oil light could also come on in the following
situations:
The light will come on briey when the ignition
is turned on to show that it is working properly.
If it does not come on with the ignition on,
there may be a problem with the fuse or bulb.
Have it xed right away.
Sometimes when the engine is idling at a stop,
a chime will sound and the light may blink on
and off. This is normal.
{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.
Security Light
For information regarding
this light and the vehicle’s
security system, see
Theft-Deterrent System
on page 2-22.
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BATTERY VOLTAGE HIGH
This symbol appears
with this message.
This message displays when the electrical charging
system is overcharging the battery. When the system
detects that the battery voltage is above an estimated
16 volts, this message displays.
To reduce the charging overload, use the vehicle’s
accessories:
Turn on the exterior lamps and radio.
Set the climate control on AUTO and the
fan speed on the highest setting.
Turn the rear window defogger on.
The normal battery voltage range is 11.5 to 15.5 volts
when the engine is running. To monitor battery
voltage on the DIC, press the information button until
BATTERY VOLTS displays.
BATTERY VOLTAGE LOW
This symbol appears
with this message.
This message displays when the electrical system is
charging less than 10 volts or the battery has been
drained.
If this message appears immediately after starting the
engine, it is possible that the generator can still recharge
the battery. The battery should recharge while driving,
but may take a few hours to do so. Consider using
an auxiliary charger to boost the battery after returning
home or to a nal destination. Follow the manufacturer’s
instructions.
If this message appears while driving or after starting
your vehicle and stays on, have it checked immediately
to determine the cause of this problem.
To help the generator recharge the battery quickly,
reduce the load on the electrical system by turning off
the accessories.
The normal battery voltage range is 11.5 to 15.5 volts.
To monitor battery voltage on the DIC, press the
information button until BATTERY VOLTS displays.
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CHANGE ENGINE OIL SOON
This message displays when the engine oil needs to be
changed. See your dealer/retailer. SeeEngine Oil on
page 5-18andScheduled Maintenance on page 6-4for
more information.
After resetting the CHANGE ENGINE OIL SOON
message by clearing it from the display, reset the engine
oil life system separately. For more information on
resetting the engine oil life system, seeEngine Oil Life
System on page 5-21.
CHECK BRAKE FLUID
This message displays if the ignition is on to inform the
driver that the brake uid level is low. Have the brake
system serviced by your dealer/retailer as soon as
possible. SeeBrake System Warning Light on page 3-64
for more information.
CHECK GAS CAP
This message displays when the fuel cap has not been
fully tightened. Recheck the fuel cap to ensure that it
is on and tightened properly.
CHECK TIRE PRESSURE
This message displays when the pressure in one or
more of the vehicle’s tires needs to be checked. If a tire
pressure message appears on the DIC, stop as soon
as you can. Have the tire pressures checked and set
to those shown on the Tire Loading Information
label. SeeTires on page 5-57,Loading Your Vehicle on
page 4-26, andInflation - Tire Pressure on page 5-66.
The DIC also shows the tire pressure values. See
DIC Operation and Displays on page 3-74. If the tire
pressure is low, the low tire pressure warning light
comes on. SeeTire Pressure Light on page 3-67.
CHECK WASHER FLUID
This symbol appears
with this message.
This message displays when the windshield washer
uid is low. Fill the windshield washer uid reservoir
as soon as possible. SeeWindshield Washer Fluid
on page 5-40for more information.
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Audio System(s)
Determine which radio your vehicle has and then
read the pages following to familiarize yourself with
its features.
{CAUTION:
This system provides you with far greater
access to audio stations and song listings.
Giving extended attention to entertainment
tasks while driving can cause a crash and you
or others can be injured or killed. Always keep
your eyes on the road and your mind on the
drive — avoid engaging in extended searching
while driving.
Keeping your mind on the drive is important for
safe driving. SeeDefensive Driving on page 4-2.
Here are some ways in which you can help avoid
distraction while driving.While your vehicle is parked:
Familiarize yourself with all of its controls.
Familiarize yourself with its operation.
Set up your audio system by presetting your
favorite radio stations, setting the tone, and
adjusting the speakers. Then, when driving
conditions permit, you can tune to your favorite
radio stations using the presets and steering
wheel controls if the vehicle has them.
Notice:Before adding any sound equipment to
your vehicle, such as an audio system, CD player,
CB radio, mobile telephone, or two-way radio, make
sure that it can be added by checking with your
dealer/retailer. Also, check federal rules covering
mobile radio and telephone units. If sound equipment
can be added, it is very important to do it properly.
Added sound equipment may interfere with the
operation of your vehicle’s engine, radio, or other
systems, and even damage them. Your vehicle’s
systems may interfere with the operation of sound
equipment that has been added.
Your vehicle has a feature called Retained Accessory
Power (RAP). With RAP, the audio system can be
played even after the ignition is turned off. SeeRetained
Accessory Power (RAP) on page 2-29for more
information.
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