2003 BUICK CENTURY headlamp

Daytime Running Lamps/Automatic
Headlamp System
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the
day. DRL can be helpful in many different driving
conditions, but they can be especially helpful in the short
periods after dawn and before sunset. Fully functional
daytime running lamps are required on all vehicles
®rst sold in Canada.
A light sensor on top of the instrument panel makes the
DRL work, so be sure it isn't covered.
The DRL system will make your front turn signal lamps
come on when the following conditions are met:
·The ignition is on,
·the exterior lamps control is off and
·the parking brake is released.
While the DRL are on, only your front turn signal lamps
will be on. The headlamps, taillamps, sidemarker
and other lamps won't be on. Your instrument panel
won't be lit up either.When it's dark enough outside, your front turn signal
lamps will turn off and your vehicle's headlamps
and parking lamps will turn on. The other lamps that
come on with your headlamps will also come on.
When it's bright enough outside, your headlamps will
go off and your front turn signal lamps will come on.
To idle your vehicle with the DRL and automatic
headlamp control off, set the parking brake while the
ignition is in OFF or LOCK. Then start your vehicle. The
DRL, headlamps and parking lamps will stay off until
you release the parking brake.
To turn off the automatic headlamp feature when it's
dark outside, move the exterior lamps control to
the parking lamp position. Your parking lamps will
remain illuminated and your headlamps will turn off.
As with any vehicle, you should turn on the regular
headlamp system when you need it.
3-12

Delayed Headlamps
Delayed headlamp illumination provides a period of
exterior lighting as you leave your vehicle's area. The
feature is activated when your vehicle's headlamps
are on due to the automatic headlamp control feature
described previously in this section, and when your
vehicle's ignition is turned off. Your headlamps will then
remain on until the exterior lamps control is moved
from OFF to the parking lamp position or until a
90 second lighting period has ended.
If you turn off the ignition with the exterior lamps control
in the parking lamp or headlamp position, the delayed
headlamp illumination cycle will not occur.
You can customize the vehicle to activate delayed
headlamp illumination when your vehicle's ignition is
turned off under the conditions described above, or you
may choose not to activate this feature under any
conditions.
You can turn the feature on and off when you perform
the following sequence:
1. Turn the ignition key to RUN.
2. Close all the doors.3. Press and hold the power door lock switch. While
holding the door lock switch, cycle the exterior
lamps control on and then off two times.
4. Release the power door lock switch. These steps
must be carried out in a time period of less than
10 seconds, followed by a delay period of no more
than 10 seconds.
5. Then, press and hold the power door unlock switch.
While holding the door unlock switch, turn the
exterior lamps control on and then off two times.
Release the courtesy door unlock switch. These
operations must be carried out in a time period of
less than 10 seconds.
After releasing the door unlock switch, a single chime
will be heard if the delayed headlamp illumination
function has been disabled; two chimes will be heard if
the feature has been enabled. Disconnecting the
vehicle's battery for up to a year will not change the
programmed operation for this feature.
3-13

Of course, traction is reduced when water, snow, ice,
gravel or other material is on the road. For safety, you'll
want to slow down and adjust your driving to these
conditions. It is important to slow down on slippery
surfaces because stopping distance will be longer and
vehicle control more limited.
While driving on a surface with reduced traction, try
your best to avoid sudden steering, acceleration
or braking (including engine braking by shifting to a
lower gear). Any sudden changes could cause the tires
to slide. You may not realize the surface is slippery
until your vehicle is skidding. Learn to recognize warning
clues Ð such as enough water, ice or packed snow
on the road to make a ªmirrored surfaceº Ð and slow
down when you have any doubt.
If you have the anti-lock braking system, remember:
It helps avoid only the braking skid. If you do not have
anti-lock, then in a braking skid (where the wheels
are no longer rolling), release enough pressure on the
brakes to get the wheels rolling again. This restores
steering control. Push the brake pedal down steadily
when you have to stop suddenly. As long as the wheels
are rolling, you will have steering control.Driving at Night
Night driving is more dangerous than day driving. One
reason is that some drivers are likely to be impaired Ð by
alcohol or drugs, with night vision problems, or by fatigue.
Here are some tips on night driving.
·Drive defensively.
·Don't drink and drive.
·Adjust your inside rearview mirror to reduce the
glare from headlamps behind you.
4-16

·Since you can't see as well, you may need to slow
down and keep more space between you and
other vehicles.
·Slow down, especially on higher speed roads. Your
headlamps can light up only so much road ahead.
·In remote areas, watch for animals.
·If you're tired, pull off the road in a safe place
and rest.
No one can see as well at night as in the daytime. But as
we get older these differences increase. A 50-year-old
driver may require at least twice as much light to see the
same thing at night as a 20-year-old.
What you do in the daytime can also affect your night
vision. For example, if you spend the day in bright
sunshine you are wise to wear sunglasses. Your eyes
will have less trouble adjusting to night. But if you're
driving, don't wear sunglasses at night. They may
cut down on glare from headlamps, but they also make
a lot of things invisible.You can be temporarily blinded by approaching
headlamps. It can take a second or two, or even several
seconds, for your eyes to readjust to the dark. When
you are faced with severe glare (as from a driver
who doesn't lower the high beams, or a vehicle with
misaimed headlamps), slow down a little. Avoid staring
directly into the approaching headlamps.
Keep your windshield and all the glass on your vehicle
clean Ð inside and out. Glare at night is made much
worse by dirt on the glass. Even the inside of the glass
can build up a ®lm caused by dust. Dirty glass makes
lights dazzle and ¯ash more than clean glass would,
making the pupils of your eyes contract repeatedly.
Remember that your headlamps light up far less of a
roadway when you are in a turn or curve. Keep
your eyes moving; that way, it's easier to pick out dimly
lighted objects. Just as your headlamps should be
checked regularly for proper aim, so should your eyes
be examined regularly. Some drivers suffer from
night blindness Ð the inability to see in dim light Ð and
aren't even aware of it.
4-17

{CAUTION:
Snow can trap exhaust gases under your
vehicle. This can cause deadly CO (carbon
monoxide) gas to get inside. CO could
overcome you and kill you. You can't see it or
smell it, so you might not know it is in your
vehicle. Clear away snow from around the
base of your vehicle, especially any that is
blocking your exhaust pipe. And check around
again from time to time to be sure snow
doesn't collect there.
Open a window just a little on the side of the
vehicle that's away from the wind. This will
help keep CO out.Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little
faster than just idle. That is, push the accelerator
slightly. This uses less fuel for the heat that you get and
it keeps the battery charged. You will need a
well-charged battery to restart the vehicle, and possibly
for signaling later on with your headlamps. Let the
heater run for a while.
Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine
again and repeat this only when you feel really
uncomfortable from the cold. But do it as little as
possible. Preserve the fuel as long as you can. To help
keep warm, you can get out of the vehicle and do
some fairly vigorous exercises every half hour or so until
help comes.
4-30

Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside
of Your Vehicle...........................................5-4
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Speci®cations....................................5-5
California Fuel...............................................5-6
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-7
Filling Your Tank............................................5-7
Filling a Portable Fuel Container.......................5-9
Checking Things Under the Hood....................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-13
Engine Air Cleaner/Filter................................5-18
Automatic Transaxle Fluid..............................5-19
Engine Coolant.............................................5-23
Radiator Pressure Cap..................................5-26
Engine Overheating.......................................5-26
Cooling System............................................5-29
Power Steering Fluid.....................................5-36
Windshield Washer Fluid................................5-38
Brakes........................................................5-39Battery........................................................5-42
Jump Starting...............................................5-43
Headlamp Aiming...........................................5-49
Bulb Replacement..........................................5-51
Halogen Bulbs..............................................5-51
Headlamps..................................................5-51
Front Turn Signal and Parking Lamps..............5-52
Center High-Mounted Stoplamp (CHMSL).........5-53
Taillamps, Turn Signal, and Stoplamps............5-54
Back-Up Lamps............................................5-55
Replacement Bulbs.......................................5-55
Windshield Wiper Blade Replacement..............5-56
Tires..............................................................5-57
In¯ation Ð Tire Pressure...............................5-57
Tire Pressure Monitor System.........................5-58
Tire Inspection and Rotation...........................5-60
When It Is Time for New Tires.......................5-61
Buying New Tires.........................................5-62
Uniform Tire Quality Grading..........................5-63
Wheel Alignment and Tire Balance..................5-64
Wheel Replacement......................................5-64
Tire Chains..................................................5-66
If a Tire Goes Flat........................................5-66
Changing a Flat Tire.....................................5-67
Compact Spare Tire......................................5-78
Section 5 Service and Appearance Care
5-1

Appearance Care............................................5-79
Cleaning the Inside of Your Vehicle.................5-79
Care of Safety Belts......................................5-82
Weatherstrips...............................................5-82
Cleaning the Outside of Your Vehicle..............5-82
Sheet Metal Damage.....................................5-84
Finish Damage.............................................5-84
Underbody Maintenance................................5-85
Chemical Paint Spotting.................................5-85
Vehicle Care/Appearance Materials..................5-85
Vehicle Identi®cation......................................5-87
Vehicle Identi®cation Number (VIN).................5-87
Service Parts Identi®cation Label.....................5-87Electrical System............................................5-88
Add-On Electrical Equipment..........................5-88
Headlamp Wiring..........................................5-88
Windshield Wiper Fuses................................5-88
Power Windows and Other Power Options.......5-88
Fuses and Circuit Breakers............................5-89
Capacities and Speci®cations..........................5-94
Capacities and Speci®cations.........................5-94
Normal Maintenance Replacement Parts..........5-95
Normal Maintenance Replacement Parts..........5-95
Section 5 Service and Appearance Care
5-2

Headlamp Aiming
Your vehicle has a headlamp system equipped with
horizontal and vertical aim indicators. The aim has been
pre-set at the factory and should need no further
adjustment. This is true even though your vertical and
horizontal aim indicators may not fall exactly on the
ª0º (zero) marks on their scales.
If your vehicle is damaged in an accident, the headlamp
aim may be affected. Aim adjustment may be necessary
if it is difficult to see lane markers (for horizontal
aim), or if oncoming drivers ¯ash their high beams at
you (for vertical aim). If you believe your headlamps
need to be re-aimed, we recommend that you take it to
your dealer for service; however, it is possible for
you to re-aim your headlamps as described in the
following procedure.
Notice:To make sure your headlamps are aimed
properly, read all the instructions before beginning.
Failure to follow these instructions could cause
damage to headlamp parts.To check the aim, the vehicle should be properly
prepared as follows:
·The headlamps must be off for one hour prior to
aiming and must remain off during this procedure.
·The vehicle must have all four tires on a perfectly
level surface.
·If necessary, pads may be used on an uneven
surface.
·The vehicle should not have any snow, ice or mud
attached to it.
·The vehicle should be fully assembled and all other
work stopped while headlamp aiming is being done.
·There should not be any cargo or loading of the
vehicle, except it should have a full tank of fuel and
one person or 160 lbs (75 kg) on the driver's seat.
·Close all doors.
·Tires should be properly in¯ated.
·Rock the vehicle to stabilize the suspension.
5-49