engine CADILLAC STS 2008 1.G Service Manual

Lane Departure Warning Light
Your vehicle may have
the lane departure
warning system.
This light will come on green, briey, when the vehicle
is started to show that it is working. This light will
also come on green if the system detects a left or
right lane marking. This light will change to amber
and ash and three beeps will sound if you cross a
detected lane marking without using your turn signal.
For more information, see the Index in the Navigation
Manual.
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, see
Overheated Engine Protection Operating Mode on
page 5-31. SeeEngine Overheating on page 5-29
andDIC Warnings and Messages on page 3-80for
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 5-29for 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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Fuel Gage
The fuel gage shows
approximately how much
fuel is in the fuel tank.
It works only when
the engine is on.
If the fuel supply gets low, the “FUEL LEVEL LOW”
message will appear on the Driver Information Center
(DIC) and a single chime will sound. SeeDIC Warnings
and Messages on page 3-80for more information.All of the following 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
Operation and Displays on page 3-74for 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 in the center.
SeeAutomatic Transmission Operation on page 2-32
for 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 2-32for 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 Operation 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, 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.
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DIC Buttons (Uplevel)
If your vehicle has
a 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, engine oil life, if your vehicle has this feature,
and display units. See “MPH (km)” later in this section
for more information on the digital speed display.
«~ª(Head-Up Display):Press this button to
change the position of the HUD on the windshield.
Press the top part of the button to move the HUD image
up. Press the bottom part of the button to move the
HUD image down.
To adjust the brightness of the HUD image, see
Head-Up Display (HUD) on page 3-43.
For information on adjusting the instrument panel
brightness, seeInstrument Panel Brightness
on page 3-41.
4// (Reset):Press this button to reset certain DIC
features and to acknowledge DIC warning messages
and clear them from the DIC display.
3(Trip Information):Press this button to scroll
through the odometer, trip odometer A and trip
odometer B. To reset each trip odometer, either press
the reset button or press and hold the trip information
button until the trip odometer displayed returns to zero.
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