2005 CADILLAC STS service

Charging System Light
When you turn the engine
on, this light will come on
briey to show that the
generator and battery
charging systems
are working properly.
If this light stays on, your vehicle needs service. You
should take your vehicle to the dealer at once. To save
your battery until you get there, turn off all accessories.
SeeDIC Controls and Displays on page 3-74for
more information.
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.
United StatesCanada
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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 4-35.
{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.
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, turn the ignition 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. See
Brake System Warning Light on page 3-64.
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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 5-62for
more information.
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 4-8for more information.
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Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with 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.
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.
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.
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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 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 2-22. 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 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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Information Display Menu Items
The following display menu items can be displayed
by pressing the information button.
ENGLISH DISPLAY UNITS
(METRIC DISPLAY UNITS)
This display allows you to select between English and
metric units of measurement if your vehicle has the
uplevel DIC. Press the reset button to switch between
English and metric units.
ENGINE OIL LIFE
This display, if equipped, shows the estimated oil life
remaining. If you see 99% ENGINE OIL LIFE on
the display, that means that 99% of the current oil life
remains.
When the oil life is depleted, the CHANGE ENGINE OIL
SOON message will appear on the display. You
should change your oil as soon as possible. In addition
to the engine oil life system monitoring the oil life,
additional maintenance is recommended in the
Maintenance Schedule in this manual. SeeScheduled
Maintenance on page 6-4andEngine Oil on page 5-15.
After an oil change, reset the ENGINE OIL LIFE
display by pressing the reset button for three seconds.
The display will show 100% ENGINE OIL LIFE after
it has been reset. Also clear the CHANGE ENGINE OIL
SOON message from the display. SeeEngine Oil
Life System on page 5-18for more information.
TIRE PRESSURE
This display, if equipped, shows the air pressure of each
road tire in either pounds per square inch (psi) or
kilopascals (kPa). If the tire pressure is normal, the value
will display. If the tire pressure is low, LOW will appear on
the display with the value. If the tire pressure is high,
HIGH will appear on the display with the value. Press the
information button to scroll through the following displays:
RR TIRE:This display shows the air pressure in the
passenger’s side rear tire.
LR TIRE:This display shows the air pressure in the
driver’s side rear tire.
RF TIRE:This display shows the air pressure in the
passenger’s side front tire.
LF TIRE:This display shows the air pressure in the
driver’s side front tire.
If the tire pressure display shows dashes instead of a
value, there may be a problem with your vehicle. If this
consistently occurs, see your GM dealer for service.
BATTERY VOLTS
This display shows the current battery voltage. If the
voltage is in the normal range, the value will display. For
example, the display may read 13.2 BATTERY VOLTS.
If the voltage is low, the display will have LOW after it.
If the voltage is high, the display will have HIGH after it.
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AUTOMATIC LIGHTS OFF
This message will display when the automatic
headlamps are turned off. SeeHeadlamps on page 3-33
for more information.
AUTOMATIC LIGHTS ON
This message will display when the automatic
headlamps are turned on. SeeHeadlamps on page 3-33
for more information.
BATTERY NOT CHARGING SERVICE
CHARGING SYS (System)
This symbol appears with
the BATTERY NOT
CHARGING SERVICE
CHARGING SYS
message.
This message will display when a problem with the
charging system has been detected. Have your vehicle
serviced by your GM dealer.
BATTERY SAVER ACTIVE
This message will display when the system detects that
the battery voltage is dropping beyond a reasonable
level. The battery saver system will start reducing certain
features of the vehicle that you may not be able to
notice. At the point that the features are disabled, this
message is displayed. It means that the vehicle is trying
to save the charge in the battery.
Turn off all unnecessary accessories to allow the battery
to recharge.
The normal battery voltage range is 11.5 to 15.5 volts.
You can monitor battery voltage on the DIC by pressing
the information button until you nd BATTERY VOLTS.
BATTERY VOLTAGE HIGH
This symbol appears with
the BATTERY VOLTAGE
HIGH message.
This message will display when the electrical charging
system is overcharging the battery. When the system
detects that the battery voltage is above approximately
16 volts, this message will be displayed.
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