engine CADILLAC STS 2007 1.G Service Manual

Anti-Lock Brake System
Warning Light
With the Anti-Lock
Brake System (ABS),
this 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 brake system warning
light is not on, you still have brakes, but you do not
have antilock brakes. SeeBrake System Warning
Light on page 248for more information.
If the light stays on, press the ignition Acc. button.
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 systemwarning 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 248for more information.
The ABS 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.
This light will also come on when one or more of
your tires are signicantly underinated.
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A CHECK TIRE PRESSURE DIC message will
accompany the light. Stop and check your tires as
soon as it is safe to do so. If underinated,
inate to the proper pressure. See Tires for more
information. This light will ash for approximately
60 seconds and then turn on solid if a problem
is detected with the Tire Pressure Monitor system.
SeeTire Pressure Monitor System on page 433,
Tires on page 421andDIC Warnings and
Messages on page 264for more information.
Traction Control System (TCS)
Warning Light
If the Traction
Control (TC) warning
light comes on and
stays on, there may be
a problem with the
traction control system.The TC 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 on/off button
located on the console.
If the TC 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. See
Traction Control System (TCS) on page 323and
StabiliTrak®System on page 326for more
information.
Also seeCompetitive Driving Mode (STS-V) on
page 325for more information.
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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 395. SeeEngine
Overheating on page 393andDIC Warnings and
Messages on page 264for more information.
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 393for more information.
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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, 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 363.
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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.
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 368.
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.
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Did you just drive through a deep puddle of water?
If so, your vehicle’s 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 365. Poor fuel
quality will cause the 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.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 111. 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.
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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 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.
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.
255

Highbeam On Light
This light comes on
whenever the
high-beam headlamps
are on.
See “Intellibeam™ Intelligent High-Beam
Headlamp Control System” underHeadlamps on
page 211andHeadlamp High/Low-Beam
Changer on page 183for more information.
Fuel Gage
The fuel gage shows
approximately how
much fuel is in the tank.
It works only when
the engine is on.If the fuel supply gets low, the Fuel Level Low
message will appear on the DIC and a single
chime will sound. SeeDIC Warnings and
Messages on page 264for more information.
Here are a few concerns some owners have had
about the fuel gage. All of these situations are
normal and do not indicate that anything is wrong
with the fuel gage:
At the gas station the gas pump shuts off
before the gage reads full.
The gage may change when you turn, stop
quickly or accelerate quickly.
It takes a little more or less fuel to ll the tank
than the gage indicated. For example, the gage
may have indicated that the tank was half full,
but it actually took a little more or less than half
the tank’s capacity to ll the tank.
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Driver Information Center (DIC)
The Driver Information Center (DIC) gives you the
status of many of your vehicle’s systems. The DIC
is also used to display warning/status messages.
All messages will appear in the DIC display located
at the bottom of the instrument panel cluster, below
the tachometer and speedometer. The DIC buttons
are located on the instrument panel, to the left of
the steering wheel.
The DIC comes on when the ignition is on. After a
short delay, the DIC will display the current
driver and the information that was last displayed
before the engine was turned off.
The top line of the DIC display shows the vehicle
system information and the warning/status
messages. The bottom line of the DIC display
shows either the odometer, the trip odometer A or
the trip odometer B information on the left side.
Only one odometer can appear at a time. See “Trip
Information” underDIC Controls and Displays
on page 258for information on changing the
display to show the odometer or trip odometer
information. The bottom line of the DIC display
also shows the outside temperature on the
right side and the shift lever position indicator inthe center. SeeAutomatic Transmission Operation
on page 116for more information on the shift
lever positions.
When the sport mode is active, an S will appear
next to the shift position indicator on the center of
the DIC display. When the manual mode is
active, an M will appear on the DIC display. When
the normal mode is active, only the shift position
indicator will appear. While the Driver Shift
Control (DSC) feature is active, the DIC will
change to show the selected gear. See “Driver
Shift Control (DSC)” underAutomatic Transmission
Operation on page 116for more information.
If a problem is detected, a warning message will
appear on the display. Be sure to take any
message that appears on the display seriously and
remember that clearing the message will only make
the message disappear, not correct the problem.
DIC Controls and Displays
The Driver Information Center (DIC) has different
modes which can be accessed by pressing
the four DIC buttons located on the instrument
panel, to the left of the steering wheel.
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DIC Buttons (Base Level)
If your vehicle does
not have a Head-Up
Display (HUD),
these are the
buttons for the DIC.
«4ª(Information):Press the top or bottom of
this button to scroll through the available vehicle
information displays which include digital
speed display, if your vehicle has this feature, fuel
range, fuel economy, fuel used, average speed,
timer, battery voltage, tire pressure, if your vehicle
has a Tire Pressure Monitor (TPM) system, and
engine oil life, if your vehicle has this feature.If you have an STS-V, the DIC also has additional
vehicle information displays which include engine
boost, engine oil temperature, oil pressure, and
transmission uid temperature.
See “MPH (km)” later in this section for more
information on the digital speed display.
AB
300 (Trip Information):Press the top of
this button to scroll through the odometer, trip
odometer A and trip odometer B. Press and hold
the bottom of this button to reset each trip
odometer back to zero.
4// (Reset):Press this button to reset certain DIC
features and to acknowledge DIC warning
messages and clear them from the DIC display.
EM (English/Metric):Press this button to change
the display from English to metric.
259