2003 CADILLAC CTS Owners Manual

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Warning Lights, Gages and
Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause an
expensive repair or replacement. Paying attention to
your warning lights and gages could also save you or
others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle's functions. As you
will see in the details on the next few pages, some
warning lights come on briefly when you start the
engine just to let you know they're working. If you are
familiar with this section, you should not be alarmed
when this happens.Gages can indicate when there may be or is a problem
with one of your vehicle's functions. Often gages and
warning lights work together to let you know when
there's a problem with your vehicle.
When one of the warning lights comes on and stays on
when you are driving, or when one of the gages shows
there may be a problem, check the section that tells you
what to do about it. Please follow this manual's advice.
Waiting to do repairs can be costly
-- and even
dangerous. So please get to know your warning lights
and gages. They're a big help.
Your vehicle also has a Driver Information Center (DIC)
that works along with the warning lights and gages. See
ªDriver Information Center (DIC)º later in this section
for more information.

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Safety Belt Reminder Light
When the key is turned to ON or START, a chime will
come on for several seconds to remind people to fasten
their safety belts, unless the driver's safety belt is
already buckled.
The safety belt light will
also come on and stay on
for several seconds, then it
will flash for several more.
If the driver's belt is already buckled, neither the chime
nor the light will come on.
Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows the air bag symbol. The system
checks the air bag's electrical system for malfunctions.
The light tells you if there is an electrical problem. The
system check includes the air bag sensors, the air bag
modules, the wiring and the diagnostic module. For
more information on the air bag system, see ªAir Bagº
in the Index.
This light will come on
when you start your vehicle,
and it will flash for a few
seconds. Then the light
should go out. This means
the system is ready.
If the air bag readiness light stays on after you start the
vehicle or comes on when you are driving, your air bag
system may not work properly. Have your vehicle
serviced right away.

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CAUTION:
If the air bag readiness light stays on after you
start your vehicle, it means the air bag system
may not be working properly. The air bags in
your vehicle may not inflate in a crash, or they
could even inflate without a crash. To help avoid
injury to yourself or others, have your vehicle
serviced right away if the air bag readiness light
stays on after you start your vehicle.
The air bag readiness light should flash for a few
seconds when you turn the ignition key to ON. If the
light doesn't come on then, have it fixed so it will be
ready to warn you if there is a problem.
If there is a problem with the air bag system in your
vehicle, the Service Air Bag message will appear on the
DIC display. See ªService Air Bag Messageº later in
this section for more information.
Charging System Light
When you turn the key to
ON or START, this light
will come on briefly 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.

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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.
United States Canada
This light should come on briefly when you turn
the ignition key to ON. If it doesn't come on then,
have it fixed so it will be ready to warn you if there's
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 doesn't release
fully. If it stays on after your parking brake is fully
released, it means you have a brake problem.
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 floor.
It may take longer to stop. If the light is still on, have the
vehicle towed for service. See ªTowing Your Vehicleº in
the Index.
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've
pulled off the road and stopped carefully, have
the vehicle towed for service.

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Anti-Lock Brake System Warning Light
With the anti-lock brake
system, the light(s) will
come on when your engine
is started and may stay
on for several seconds.
That's 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 don't have antilock brakes. See ªBrake
System Warning Lightº earlier in this section.If the light stays on, turn the ignition to OFF. Or, if the
light comes on when you're 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're driving, your vehicle needs
service. If the regular brake system warning light isn't
on, you still have brakes, but you don't have anti
-lock
brakes. If the regular brake system warning light is also
on, you don't have anti
-lock brakes and there's a
problem with your regular brakes. See ªBrake System
Warning Lightº earlier in this section.
The anti
-lock brake system warning light will come on
briefly when you turn the ignition key to ON. This is
normal. If the light doesn't come on then, have it fixed
so it will be ready to warn you if there is a problem.
If the ABS light stays on or comes on while you are
driving, pull off the road as soon as possible and stop
carefully. Try resetting the system by turning the
ignition off then back on. If the ABS light still stays on
or comes back on again while you are driving, your
vehicle needs service. Have the anti
-lock brake system
inspected as soon as possible.

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Traction Control System Warning
(TRAC OFF) Light
If the TRAC OFF
warning light comes on
and stays on, there may
be a problem with the
traction control system.
The TRAC OFF light will come on briefly when you
turn the ignition to ON. If it doesn't come on then,
have it fixed 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 Traction On/Off button.
The traction control TC button is located in the
glove box.
If the TRAC OFF light stays on or comes on while you
are driving, pull off the road as soon as possible and stop
carefully. Try resetting the system by turning the
ignition off then back on. 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 ªTraction Control
Systemº in the Index.

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Engine Coolant Temperature
Warning Light
This light tells you that your
engine has overheated.
This light will come on when you first start the vehicle
as a check to let you know that the light is working. It
will go out after a few seconds. If the light does not
come on, the bulb may be burned out. See your dealer
for assistance in changing the bulb.
If the light does not go out or if the light comes on and
stays on while you are driving, your vehicle may have a
problem with the cooling system. You should stop the
vehicle and turn off the engine as soon as possible to
avoid damage to the engine. A warning chime will
sound when this light is on, also.
See ªEngine Overheatingº in the Index.
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.

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NOTICE:
If you keep driving your vehicle with this light
on, after a while, 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:
Modifications 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.
Modifications 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, as a check to show you it is
working, when the ignition is on and the engine is not
running. If the light doesn't come on, have it repaired.
This light will also come on during a malfunction in one
of two ways:

Light Flashing
-- A misfire condition has been
detected. A misfire increases vehicle emissions and
may damage the emission control system on your
vehicle. Dealer or qualified service center diagnosis
and service may be required.

Light On Steady
-- An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center diagnosis and
service may be required.