2001 BUICK CENTURY service

2-56 OnStar System Limitations
Complete limitations can be found on the Subscriber
Services Agreement.
OnStar Service is:

available in the 48 contiguous United States, Alaska,
Hawaii and Canada;

available when the vehicle is within the operating
range of a cellular provider;

subject to limitations caused by atmospheric
conditions, such as severe weather or topographical
conditions, such as mountainous terrain;

subject to cellular carrier equipment limitations.Global positioning capabilities used to deliver
OnStar Service will not be available if satellite signals
are obstructed.
OnStar will not function if the vehicle's battery is
discharged or disconnected. It may also be inoperative
if the vehicle is in an accident and the OnStar or vehicle
electrical system components are damaged.
Safety and security services are provided by existing
governmental emergency service providers. OnStar
will use reasonable efforts to contact the appropriate
emergency service provider and request assistance but
cannot promise that they will respond to the call in a
timely manner or at all.

2-63 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 modules, the wiring
and the crash sensing and 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.
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 RUN. If the light
doesn't come on then, have it fixed so it will be ready
to warn you if there is a problem.

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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 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.
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.
Anti-Lock Brake System Warning Light
United States Canada
The anti
-lock brake system warning light should come on
for a few seconds when you turn the ignition key to
RUN. If the anti
-lock brake system warning light stays
on longer than normal after you've started your engine,
turn the ignition off. Or, if the light comes on and stays
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, the anti
-lock brake system needs service
and you don't have anti
-lock brakes. The brake pedal
may be harder to push, or it may go to the floor. It may
take longer to stop. Adjust your driving accordingly.
The anti
-lock brake system warning light should
come 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 ready to warn you if there is a problem.

2-66 Enhanced Traction System Warning Light
(3100 V6 Engine)
The Enhanced Traction System warning light may come
on for the following reasons:

If you turn the system off by shifting to SECOND (2)
or FIRST (1), the warning light will come on and stay
on. To turn the system back on, shift to THIRD (3) or
AUTOMATIC OVERDRIVE (
). See ªEnhanced
Traction Systemº in the Index.

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.

2-68 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.
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.

2-69 Low Tire Light
The low tire inflation
monitor system can
alert you to a large
change in the pressure
in one tire.
After the system has ªlearnedº tire pressures with
properly inflated tires, the LOW TIRE light will come
on if the pressure in one tire becomes 12 psi (83 kPa)
lower than the other three tires. The low tire inflation
monitor system won't alert you if the pressure in more
than one tire is low, if the system is not yet calibrated, or
if the vehicle is moving faster than 70 mph (110 km/h).
When the LOW TIRE light comes on, you should stop
as soon as you can and check all your tires for damage.
(If a tire is flat, see ªIf a Tire Goes Flatº in the Index.)
Also check the tire pressure in all four tires as soon as
you can. See ªInflation
- Tire Pressureº in the Index.
The light will stay on (while the ignition is on) until you
reset (calibrate) the system. See ªLow Tire Inflation
Monitor Systemº in the Index.
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.

2-70
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, 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 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.
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.

2-71
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.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.