ignition BUICK CENTURY 2000 Workshop Manual

3-26
Activating the Theft-Deterrent Feature
The instructions which follow explain how to enter your
secret code to activate the THEFTLOCK system. It is
recommended that you read through all nine steps
before starting the procedure.
If you allow more than 15 seconds to elapse between
any steps, the radio automatically reverts to time and
you must start the procedure over at Step 4.
1. Write down any three or four
-digit number from
000 to 1999 and keep it in a safe place separate from
the vehicle.
2. Turn the ignition to ACCESSORY or RUN.
3. Turn the radio off.
4. Press the 1 and 4 buttons together. Hold them down
until
--- shows on the display. Next you will use the
secret code number which you have written down.
5. Press MIN and 000 will appear on the display.
6. Press MIN again to make the last two digits agree
with your code.
7. Press HRS to make the first one or two digits agree
with your code.8. Press AM
-FM after you have confirmed that the
code matches the secret code you have written down.
The display will show REP to let you know that you
need to repeat Steps 5 through 7 to confirm your
secret code.
9. Press AM
-FM and this time the display will show
SEC to let you know that your radio is secure.
Unlocking the Theft
-Deterrent Feature After a
Power Loss
Enter your secret code as follows; pause no more than
15 seconds between steps:
1. Turn the ignition on. LOC will appear on the display.
2. Press MIN and 000 will appear on the display.
3. Press MIN again to make the last two digits agree
with your code.
4. Press HRS to make the first one or two digits agree
with your code.
5. Press AM
-FM after you have confirmed that the
code matches the secret code you have written down.
The display will show SEC, indicating the radio is
now operable and secure.

3-27
If you enter the wrong code eight times, INOP will
appear on the display. You will have to wait an hour
with the ignition on before you can try again. When you
try again, you will only have three more chances (eight
tries per chance) to enter the correct code before
INOP appears.
If you lose or forget your code, contact your dealer.
Disabling the Theft
-Deterrent Feature
Enter your secret code as follows; pause no more than
15 seconds between steps:
1. Turn the ignition to ACCESSORY or RUN.
2. Turn the radio off.
3. Press the 1 and 4 buttons together. Hold them down
until SEC shows on the display.
4. Press MIN and 000 will appear on the display.
5. Press MIN again to make the last two digits agree
with your code.6. Press HRS to make the first one or two digits agree
with your code.
7. Press AM
-FM after you have confirmed that the
code matches the secret code you have written down.
The display will show
---, indicating that the radio is
no longer secured.
If the code entered is incorrect, SEC will appear on the
display. The radio will remain secured until the correct
code is entered.
When battery power is removed and later applied to a
secured radio, the radio won't turn on and LOC will
appear on the display.
To unlock a secured radio see ªUnlocking the
Theft
-Deterrent Feature After a Power Lossº earlier
in this section.

4-25
If you drive regularly in steep country, or if you're
planning to visit there, here are some tips that can make
your trips safer and more enjoyable.

Keep your vehicle in good shape. Check all fluid levels
and also the brakes, tires, cooling system and transaxle.
These parts can work hard on mountain roads.

Know how to go down hills. The most important
thing to know is this: let your engine do some of the
slowing down. Shift to a lower gear when you go
down a steep or long hill.
CAUTION:
If you don't shift down, your brakes could get
so hot that they wouldn't work well. You would
then have poor braking or even none going
down a hill. You could crash. Shift down to let
your engine assist your brakes on a steep
downhill slope.
CAUTION:
Coasting downhill in NEUTRAL (N) or with the
ignition off is dangerous. Your brakes will have to
do all the work of slowing down. They could get
so hot that they wouldn't work well. You would
then have poor braking or even none going down
a hill. You could crash. Always have your engine
running and your vehicle in gear when you
go downhill.

5-2
Hazard Warning Flashers
Your hazard warning flashers let you warn others. They
also let police know you have a problem. Your front and
rear turn signal lamps will flash on and off.
Press the switch located on
top of the steering column
to make your front and rear
turn signal lamps flash on
and off.
Your hazard warning flashers work no matter what
position your key is in; they even work if the key isn't
in the ignition.
To turn off the flashers, press the switch again. When
the hazard warning flashers are on, your turn signals
won't work.
Other Warning Devices
If you carry reflective triangles, you can set one up at
the side of the road about 300 feet (100 m) behind
your vehicle.

5-4
2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren't touching
each other. If they are, it could cause a ground
connection you don't want. You wouldn't be able to
start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling,
set the parking brake firmly on both vehicles
involved in the jump start procedure. Put your
automatic transaxle in PARK (P) before setting the
parking brake.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlet. Turn off all lamps
that aren't needed as well as radios. This will avoid
sparks and help save both batteries. In addition, it
could save your radio!
NOTICE:
If you leave your radio on, it could be badly
damaged. The repairs wouldn't be covered by
your warranty.
4. Open the hoods and locate the batteries. (Your
vehicle's battery is located toward the front of the
passenger's side of the engine, under a diagonal brace.)
CAUTION:
An electric fan can start up even when the engine
is not running and can injure you. Keep hands,
clothing and tools away from any underhood
electric fan.

6-15 Engine Oil Additives
Don't add anything to your oil. The recommended oils
with the starburst symbol are all you will need for good
performance and engine protection.
When to Change Engine Oil
Your vehicle has a computer that lets you know when to
change your engine oil. This is not based on mileage,
but on engine revolutions and engine operating
temperature. When the computer has calculated that the
oil needs changing, the GM Oil Life System
will
indicate that a change is necessary. The mileage between
oil and filter changes will vary depending on how you
drive your vehicle
-- usually between 3,000 miles
(5 000 km) and 7,500 miles (12 500 km) since your
last oil and filter change. Under severe conditions, the
system may come on before 3,000 miles (5 000 km).
Never drive your vehicle more than 7,500 miles
(12 500 km) or 12 months (whichever occurs first)
without an oil change.
The system won't detect dust in the oil. So, if you
drive in a dusty area, be sure to change your oil and
filter every 3,000 miles (5 000 km) or sooner.
Remember to reset the CHANGE OIL SOON light
whenever the oil is changed.How to Reset the GM Oil Life System

After changing the engine oil, the system must be reset.
With the ignition key in RUN but the engine off, fully
push and release the accelerator pedal slowly three times
within five seconds. If the CHANGE OIL SOON light
flashes, the system is resetting. Turn the key to OFF,
then start the vehicle. The oil life will change to 100%.
If the CHANGE OIL SOON light comes back on, the
system has not reset. Repeat the procedure.
What to Do with Used Oil
Did you know that used engine oil contains certain
elements that may be unhealthy for your skin and could
even cause cancer? Don't let used oil stay on your skin
for very long. Clean your skin and nails with soap and
water, or a good hand cleaner. Wash or properly throw
away clothing or rags containing used engine oil. (See
the manufacturer's warnings about the use and disposal
of oil products.)
Used oil can be a real threat to the environment. If you
change your own oil, be sure to drain all free
-flowing oil
from the filter before disposal. Don't ever dispose of oil by
putting it in the trash, pouring it on the ground, into
sewers, or into streams or bodies of water. Instead, recycle
it by taking it to a place that collects used oil. If you have
a problem properly disposing of your used oil, ask your
dealer, a service station or a local recycling center for help.

6-17
Passenger Compartment Air Filter
The passenger compartment
air filter is located
underneath your hood just
below the windshield wiper
arm, on the passenger's side
(underneath the air inlet
grille) of the vehicle.
The filter traps most of the pollen from the air entering the air
conditioning module. Like your engine's air cleaner filter,
it may need to be changed periodically. For information
on how often to change the passenger compartment air
filter, see ªMaintenance Scheduleº in the Index.
To change the passenger compartment air filter, use the
following steps:
1. Turn off the ignition when the windshield wipers are
in the up position.
2. Raise the hood.3. Disconnect the windshield washer pump hose from
the fender rail and air inlet grille.
4. Reposition the hood weatherstrip from the
passenger's side of the vehicle (peel back halfway
to center).
5. Remove the air inlet grille retainers.
6. Remove the air inlet grille.
7. Remove the passenger compartment air filter.
8. Then replace the old air filter with the new one. For
the type of filter to use, see ªNormal Maintenance
Replacement Partsº in the Index.
9. Reposition the air inlet grille.
10. Reinstall the air inlet grille retainers.
11. Reposition the hood weatherstrip.

6-39
Windshield Wiper Blade Replacement
Windshield wiper blades should be inspected at least
twice a year for wear or cracking. See ªWiper Blade
Checkº in the Index for more information.
1. Turn on the wipers to LO.
2. Turn off the ignition while the wipers are at the
outer positions of the wiper pattern. The blades are
more accessible for removal/replacement while in
this position.
3. Pull the windshield wiper arm 3 to 4 inches
(7.5 to 10 cm) away from the windshield.
4. While holding the wiper arm away from the glass,
push the release clip from under the windshield
wiper arm connecting point and slide the blade
assembly down toward the glass to remove it from
the wiper arm.
5. Slide the new wiper blade securely on the wiper arm
until you hear the release clip ªclickº into place.
For wiper blade replacement length and type, see
ªNormal Maintenance Replacement Partsº in the Index.

6-42 Tire Inflation Monitor System
The tire inflation monitor system can alert you to a large
change in the pressure of one tire. The system ªlearnsº
the pressure at each tire throughout the operating speed
range of your vehicle. The system normally takes
between 45 and 90 minutes of driving to learn the tire
pressures. This time may be longer depending on
your individual driving habits. Learning need not be
accumulated during a single trip. Once learned, the
system will remember the tire pressures until the system
is recalibrated.
After the system has learned 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 tire inflation monitor system
won't alert you if the pressure in more than one tire is
low, if the system is not properly calibrated, or if the
vehicle is moving faster than 70 mph (110 km/h).
The tire inflation monitor system detects differences in
tire rotation speeds that are caused by changes in tire
pressure. The system can alert you about a low
tire
-- but it doesn't replace normal tire maintenance.
See ªTiresº in the Index.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 come on and stay on until you turn off the
ignition or reset (calibrate) the system.
Don't reset the tire inflation monitor system without first
correcting the cause of the problem and checking and
adjusting the pressure in all four tires. If you reset the
system when the tire pressures are incorrect, the system
will not work properly and may not alert you when a tire
is low.
Any time you adjust a tire's pressure, rotate your tires,
or have one or more tires repaired or replaced, you'll
need to reset (calibrate) the tire inflation monitor
system. You'll also need to reset the system whenever
you buy new tires and whenever the vehicle's battery
has been disconnected.

6-43
To reset (calibrate) the system: turn the ignition switch
to RUN. Then press and hold the RESET button for
about five seconds. The red RESET button is located
inside your instrument panel fuse block. The fuse block
is located under the cover labeled FUSES, which is at
the end of the instrument panel on the passenger's side
of the vehicle. The RESET button is the first button in
the top row of the fuse block. The LOW TIRE light will
come on and flash three times. Then it will go off. If the
light doesn't go off, see your dealer for service.
The system completes the calibration process
during driving.
The system normally takes 15 to 20 minutes of driving
in each of three speed ranges to ªlearnº tire pressures.
The speed ranges are 15 to 40 mph (25 to 65 km/h),
40 to 65 mph (65 to 105 km/h) and above 65 mph
(105 km/h). When learning is complete, the system will
alert you after 2
-8 minutes if a tire is 12 psi (83 kPa)
different from the other three tires. Detection thresholds
may be higher and detection times may be longer on
rough roads, curves and at high speeds. The system
is not capable of detection at speeds greater than
70 mph (110 km/h).
Tire Inspection and Rotation
Tires should be rotated every 6,000 to 8,000 miles
(10 000 to 13 000 km). Any time you notice unusual wear,
rotate your tires as soon as possible and check wheel
alignment. Also check for damaged tires or wheels. See
ªWhen It's Time for New Tiresº and ªWheel
Replacementº later in this section for more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The first
rotation is the most important. See ªScheduled
Maintenance Servicesº in the Index for scheduled
rotation intervals.
When rotating your tires, always use the correct rotation
pattern shown here.