2009 CADILLAC STS check engine

Engine Coolant Temperature Gage
This gage shows
the engine coolant
temperature.
It can be used to see when the engine has warmed
up and to make sure 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 5-34for more information.
Tire Pressure Light
For vehicles with a tire
pressure light, this light
comes on briey when
the engine is started and
provides information about
tire pressures and the Tire
Pressure Monitoring
System.
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 3-79for 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 5-54for more
information.
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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 5-66
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 makes
sure that emissions are at acceptable levels for the life of
the vehicle, helping to produce a cleaner environment.
This comes on briey
while starting the engine.
If it does not come on, 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.
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. See
Accessories and Modifications on page 5-3.
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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.
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.
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 2-26. Press the bottom of the Acc. button on
the instrument panel and hold the button down forve seconds. The instrument panel, including the
check engine light, will light up and the ignition will be
on, but the engine will not start — 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, press and release
the Acc. button again to turn the ignition off and avoid
draining the vehicle’s battery.
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.
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Oil Pressure Light
For vehicles with an oil
pressure light, if there
is a problem with the oil,
the light may stay on
after the engine is started,
or comes on while
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 comes 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 sounds and the light may blink on and off.
This is normal.
{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.
Security Light
For information regarding
this light and the vehicle’s
security system, see
Theft-Deterrent System
on page 2-21.
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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.
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.
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Avoid needless heavy braking. Some people drive
in spurts — heavy acceleration followed by heavy
braking — rather than keeping pace with traffic. This is a
mistake. The brakes might not have time to cool between
hard stops. The brakes will wear out much faster if you do
a lot of heavy braking. If you keep pace with the traffic
and allow realistic following distances, you will eliminate a
lot of unnecessary braking. That means better braking
and longer brake life.
If your vehicle’s engine ever stops while you are driving,
brake normally but do not pump the brakes. If you do, the
pedal could get harder to push down. If the engine stops,
you will still have some power brake assist. But you will
use it when you brake. Once the power assist is used up,
it can take longer to stop and the brake pedal will be
harder to push.
Adding non-dealer/non-retailer accessories can affect
your vehicle’s performance. SeeAccessories and
Modifications on page 5-3.Antilock Brake System (ABS)
Your vehicle has the Antilock Brake System (ABS), an
advanced electronic braking system that will help
prevent a braking skid.
When you start the engine and begin to drive away,
ABS will check itself. You might hear a momentary
motor or clicking noise while this test is going on, and
you might even notice that the brake pedal moves
a little. This is normal.
If there is a problem with
ABS, this warning light will
stay on. SeeAntilock
Brake System (ABS)
Warning Light on
page 3-63.
Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here is what
happens with ABS:
A computer senses that the wheels are slowing down.
If one of the wheels is about to stop rolling, the computer
will separately work the brakes at each wheel.
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Competitive Driving
See your warranty book before using your vehicle for
competitive driving.
Notice:If you use your vehicle for competitive
driving, the engine may use more oil than it would
with normal use. Low oil levels can damage the
engine. Be sure to check the oil level often during
competitive driving and keep the level at or near the
upper mark that shows the proper operating range
on the engine oil dipstick. For information on how to
add oil, seeEngine Oil on page 5-18.
Driving at Night
Night driving is more dangerous than day driving
because some drivers are likely to be impaired — by
alcohol or drugs, with night vision problems, or by
fatigue.
Night driving tips include:
Drive defensively.
Do not drink and drive.
Reduce headlamp glare by adjusting the inside
rearview mirror.
Slow down and keep more space between you and
other vehicles because headlamps can only light up
so much road ahead.
Watch for animals.
When tired, pull off the road.
Do not wear sunglasses.
Avoid staring directly into approaching headlamps.
Keep the windshield and all glass on your vehicle
clean — inside and out.
Keep your eyes moving, especially during turns or
curves.
No one can see as well at night as in the daytime.
But, as we get older, these differences increase.
A 50-year-old driver might need at least twice as much
light to see the same thing at night as a 20-year-old.
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Before Leaving on a Long Trip
To prepare your vehicle for a long trip, consider having
it serviced by your dealer/retailer before departing.
Things to check on your own include:
Windshield Washer Fluid:Reservoir full? Windows
clean — inside and outside?
Wiper Blades:In good shape?
Fuel, Engine Oil, Other Fluids:All levels checked?
Lamps:Do they all work and are lenses clean?
Tires:Are treads good? Are tires inated to
recommended pressure?
Weather and Maps:Safe to travel? Have
up-to-date maps?
Highway Hypnosis
Always be alert and pay attention to your surroundings
while driving. If you become tired or sleepy, nd a
safe place to park your vehicle and rest.
Other driving tips include:
Keep the vehicle well ventilated.
Keep interior temperature cool.
Keep your eyes moving — scan the road ahead
and to the sides.
Check the rearview mirror and vehicle instruments
often.
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