1999 BUICK CENTURY engine

yellowblue
2-54

If the Enhanced Traction System warning light
comes on and stays on for an extended period of
time when the system is turned on, your vehicle
needs service. Adjust your driving accordingly.

The warning light will come on when you set your
parking brake with the engine running, and it will
stay on if your parking brake doesn't release fully.
If the transaxle shift lever is in any position other
than FIRST (1) or SECOND (2) and the warning
light stays on after your parking brake is fully
released, it means there's a problem with the system.

If the traction control system is affected by an
engine
-related problem, the system will turn off and
the warning light will come on.
When this warning light is on, the system will not limit
wheel spin. Adjust your driving accordingly.
Enhanced Traction System Active Light
The light will come on
when your Enhanced
Traction System is limiting
wheel spin.
You may feel or hear the system working, but this is
normal. Slippery road conditions may exist if this light
comes on, so adjust your driving accordingly.

yellowblue
2-55 Low Traction Light
If you have the Enhanced
Traction System, this light
will also come on when
the system is limiting
wheel spin.
You may feel or hear the system working, but this is
normal. Slippery road conditions may exist if the low
traction light comes on, so adjust your driving
accordingly. The light will stay on for a few seconds
after the Enhanced Traction System stops limiting wheel
spin. See ªEnhanced Traction Systemº in the Index.
The low traction light also comes on briefly when you
turn the ignition key to RUN. If the light doesn't come
on then, have it fixed so it will be there to tell you when
the Enhanced Traction System is active.
Engine Coolant Temperature Light
This light tells you that your
engine coolant has
overheated or your radiator
cooling fan is not working.
The light should come on briefly when your ignition is
turned on to show you that it is working.
If you have been operating your vehicle under normal
driving conditions, you should pull off the road, stop
your vehicle and turn off the engine as soon as possible.
The ªProblems on the Roadº section of this
manual shows what to do. See ªEngine Overheatingº
in the Index.

yellowblue
2-56 Engine Coolant Temperature Gage
You have a gage that shows
the engine coolant
temperature. If the gage
pointer moves into the red
area, your engine is too hot!
That reading means the same thing as the warning light.
It means that your engine coolant has overheated. If you
have been operating your vehicle under normal driving
conditions, you should pull off the road, stop your
vehicle and turn off the engine as soon as possible.
The ªProblems on the Roadº section of this
manual shows what to do. See ªEngine Overheatingº
in the Index.
Low Coolant Warning Light
If the LOW COOLANT
light comes on, your system
is low on coolant and the
engine may overheat. See
ªEngine Coolantº in the
Index and have your vehicle
serviced as soon as you can.
The light will come on briefly when your ignition is
turned on to show you that it is working properly.

yellowblue
2-58 Malfunction Indicator Lamp
(Service Engine Soon 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
SERVICE ENGINE SOON light comes on and a chime
will sound 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 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, transaxle,
exhaust 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 the SERVICE ENGINE SOON
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.

yellowblue
2-59
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.
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 you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.If the light stops flashing and remains on steady, see ªIf
the Light Is On Steadyº following.
If the light continues to flash, when it is safe to do so,
stop the vehicle. Find a safe place to park your vehicle.
Turn the key off, wait at least 10 seconds and restart the
engine. If the light remains on steady, see ªIf the Light
Is On Steadyº following. If the light is still flashing,
follow the previous steps, and drive the vehicle to your
dealer or qualified service center for service.
If the Light Is On Steady
You 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. See ªFilling Your Tankº in the Index. 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.

yellowblue
2-60
Are you low on fuel?
As your engine starts to run out of fuel, your engine may
not run as efficiently as designed since small amounts of
air are sucked into the fuel line causing a misfire. The
system can detect this. Adding fuel should correct this
condition. Make sure to install the fuel cap properly. See
ªFilling Your Tankº in the Index. It will take a few
driving trips to turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel (see
ªFuelº in the Index). 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, misfiring, 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,
have your dealer or qualified service center check the
vehicle. Your dealer has the proper test equipment and
diagnostic tools to fix any mechanical or electrical
problems that may have developed.
Oil Warning Light
If you have a problem with
your oil, this light may stay
on after you start your
engine, or come on when
you are driving.
This indicates that oil is not going through your engine
quickly enough to keep it lubricated. The engine could
be low on oil or could have some other oil problem.
Have it fixed right away.
The oil light could also come on in the
following situations:

The light will come on briefly when you turn on the
ignition to show you that it is working properly.
(If it doesn't come on with the ignition on, you may
have a problem with the fuse or bulb. Have it fixed
right away.)

Sometimes when the engine is idling at a stop, the
light may blink on and off. This is normal.

yellowblue
2-61
CAUTION:
Don't keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches fire. You or others could be burned.
Check your oil as soon as possible and have your
vehicle serviced.
NOTICE:
Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.
Low Oil Level Light
Your engine is equipped
with an oil level monitoring
system. When the ignition
key is turned on, the
LOW OIL light will come
on briefly.
If the light does not come on briefly, have it fixed so it
will be ready to warn you if there's a problem.
If the light stays on, stop the vehicle on a level surface
and turn the engine off. Check the oil level using the
engine oil dipstick. (See ªEngine Oilº in the Index.) If
the light does not flash, have the low oil level sensor
system repaired so it will be ready to warn you if there's
a problem.
The oil level monitoring system only checks oil level
during the brief period between key on and engine
crank. It does not monitor engine oil level when the
engine is running. Additionally, an oil level check is
only performed if the engine has been turned off for a
considerable period of time, allowing the oil normally in
circulation to drain back into the oil pan.

yellowblue
2-62 Change Oil Soon Light
The CHANGE OIL SOON
light should come on briefly
as a bulb check when you
start the engine. If the
light doesn't come on, have
it serviced.
If the CHANGE OIL SOON light comes on and stays
on after you start the engine, have the oil changed.
For additional information, see ªEngine Oil, When to
Changeº in the Index. To reset the Oil Life Monitor, see
ªEngine Oil Life Monitorº in the Index.
Security Light
The SECURITY light will
come on when you turn the
key to START and stay on
until the vehicle starts.It will also flash if your ignition key is too dirty or wet
for the PASS
-Key
II system to read the resistor pellet.
See ªPASS
-Key IIº in the Index.
If the resistor pellet is damaged or missing, the light will
come on.
If you're ever driving and the SECURITY light comes
on, you will be able to restart your engine if you turn it
off. Your PASS
-Key II system, however, is not working
properly and must be serviced by your dealer. Your
vehicle is not protected by the PASS
-Key II system.
Cruise Light
The CRUISE light comes
on whenever you set your
cruise control. See ªCruise
Controlº in the Index.