2004 BUICK CENTURY Owner's Manual

BLEND:This mode directs half of the air to go to the
oor outlets and half to the defroster and side window
outlets. The air-conditioning compressor will run
automatically in this setting unless the outside
temperature is below 40°F (4°C).
The right knob can also be used for the defrost mode.
Information on defrosting and defogging can be
found later in this section.
9FAN:The left knob controls the fan speed.
OFF:Turn the knob all the way counterclockwise to
turn off the fan.
LO (Low Fan Speed):This setting creates the lowest
fan speed.
HI (High Fan Speed):This setting creates the highest
fan speed.
DRIVER (Driver’s Side Temperature):The lever on
the left adjusts the air temperature for the driver’s
side outlets. Slide the lever up to raise the temperature
and down to lower the temperature.
PASSENGER (Passenger’s Side Temperature):The
lever on the right adjusts the air temperature for the
passenger’s side outlets. Slide the lever up to raise the
temperature and down to lower the temperature.
"(Air Conditioning):Press this button to turn the
air-conditioning on and off. An indicator light above the
button will come on when the air conditioning is on.
During daylight hours the interior lighting control might
need adjustment to the highest setting in order for
the indicator light to be seen. The system will cool and
dehumidify the air inside the vehicle when the A/C
indicator light is on.
On very hot days, open the windows long enough to let
hot, inside air escape. This reduces the time for the
vehicle to cool down.
For a quick cool-down on a very hot day, use MAX with
the temperature levers all the way in the blue area. If
this setting is used for long periods of time, the air in the
vehicle may become too dry.
For normal cooling on hot days, use VENT with the
temperature levers in the blue area. The system
will bring in outside air and cool it.
On cool, but sunny days, the sun may warm your upper
body, but your lower body may not be warm enough.
Select BI-LEV and set the temperature levers to a
comfortable setting. The system will bring in outside air
and direct it to your upper body, while sending slightly
warmed air to your lower body. Push the A/C button for
cooling.
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Defogging and Defrosting
Fog on the inside of the windows is a result of high
humidity causing moisture to form and condense on
the cool window glass. This can be minimized if
the climate control system is used properly. There are
two modes to clear fog or frost from the windshield
and side windows. Use the blend mode to clear
the windows of fog or moisture and warm the
passengers. Use the defrost mode to remove frost or
fog from the windshield more quickly. For best results,
clear all snow and ice from the windshield before
defrosting.
0DEF (Defrost):This setting, located on the right
knob, directs most of the air through the defroster
and the side window outlets. Some of the air is directed
to the oor and side window outlets. The air-conditioning
compressor will run automatically in this setting unless
the outside temperature is below 40°F (4°C).
To defrost the window quickly, turn the mode knob to
the defrost setting and turn the driver’s and passenger’s
temperature levers all the way to the red area.To warm passengers while keeping the windows clear,
use BLEND.
Do not drive the vehicle until all the windows are clear.
Rear Window Defogger
<
(Rear):Press the button to turn the defogger on or
off. The rear window defogger will initially run for
about 15 minutes. If it is turned on again, the rear
window defogger will only run for about seven and one
half minutes before turning off.
Do not drive the vehicle until all the windows are clear.
Notice:Using a razor blade or sharp object to
clear the inside rear window may damage the rear
window defogger. Repairs would not be covered
by your warranty. Do not clear the inside of the rear
window with sharp objects.
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Dual Automatic Climate Control
System
The vehicle may have this climate control system.
The heating, cooling and ventilation can be controlled
with it.
Automatic Operation
AUTO (Automatic):Press the AUTO button for
automatic control of the inside temperature, the air
delivery mode and the fan speed. There might be a
delay of two to three minutes before the fan comes on
when the automatic operation is used in cold weather.
For the automatic system to function, the temperature
must be set between 61°F (16°C) and 89°F (31°C).
1. Adjust the temperature to a comfortable setting.
2. Press the AUTO button.
Choosing the coldest or warmest temperature
setting will not cause the system to heat or cool
any faster.
If the system is set at the warmest temperature
setting, 90°F (32°C), hot air will be directed to the
oor, the fan will increase to the highest speed, and
the system will remain in manual mode at that
temperature. The system will not return to automatic
until the temperature setting is lowered.
If the system is set at the coldest temperature
setting, 60°F (15°C), cold interior air will be
recirculated through the air panel outlets, and the
fan will increase to the highest speed. The
system will not return to automatic until the
temperature is raised.
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In cold weather, the system will start at reduced fan
speeds to avoid blowing cold air into the vehicle
until warmer air is available. The system will
start out blowing air at the oor but may change
modes automatically as the vehicle warms up
to maintain the chosen temperature setting. The
length of time needed for warm up will depend on
the outside temperature and the length of time
that has elapsed since the vehicle was last driven.
3. Wait for the system to regulate. This may take from
10 to 30 minutes. Then, adjust the temperature, if
necessary.
Do not cover the solar sensor located in the center
of the instrument panel, near the windshield. For
more information on the solar sensor, see
“Solar Sensor” later in this section.
Manual Operation
During daylight hours, the instrument panel brightness
control might need to be adjusted to the highest setting,
in order to see the indicator lights for the various
climate control settings.
OFF:Pressing the OFF button cancels automatic
operation and places the system in manual mode.
Press the AUTO button to return to automatic operation.TEMP (Temperature):To manually adjust the
temperature inside the vehicle, press the up arrow on
the TEMP control to raise the temperature and press the
down arrow to lower the temperature. The display will
show the selection for a few seconds, and then the
outside temperature will be displayed.
When the DUAL light indicator is on, this means the
TEMP control has set the temperature for the driver.
When the DUAL light indicator light is not on, this means
the TEMP control has set the temperature for the
entire cabin.
9FAN:Press the up arrow on the FAN control to
increase fan speed and the down arrow to decrease fan
speed. Pressing the arrows cancels the automatic
operation and places the system in manual mode. Press
the AUTO button to return to automatic operation. If
the airow seems low when the fan is at the highest
setting, the passenger compartment air lter, if
equipped, may need to be replaced. For more
information seePassenger Compartment Air Filter on
page 3-26andScheduled Maintenance on page 6-4.
AIR FLOW:This control has several settings to
control the direction of airow when the system is
not in AUTO.
To access the various modes available, continue to
press the AIR FLOW up or down arrows until the desired
mode, listed below, appears in the display.
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WINDSHIELD/FLOOR:This setting directs some of the
air to the oor outlets and some to the defroster and
side window outlets. The air-conditioning compressor will
run automatically in this setting unless the outside
temperature is below 40°F (4°C).
MID/FLOOR:This mode directs airow through both
the oor and the instrument panel outlets. A small
amount of air is directed to the windshield and the side
window outlets.
MID (Instrument Panel):This mode directs air through
the instrument panel outlets.
FLOOR:This setting sends most of the air through the
outlets near the oor. The rest comes out of the
defroster and side window outlets.
VENT:Press this button to turn the air-conditioning
compressor on or off. The indicator light on the VENT
mode is lit when the compressor is turned off. The
interior brightness control might have to be adjusted to
the highest setting during the day in order to see
the indicator lamp.
VENT does not operate in the FRONT defrost mode.
RECIRC (Recirculation):Press this button to turn this
mode on or off. RECIRC limits the amount of outside
air coming into the vehicle and recirculates most of the
air inside your vehicle. It can be use to preventoutside air and odors from entering the vehicle or to
quickly heat or cool the air inside the vehicle. When this
button is pressed an indicator light will come on. The
interior brightness control might have to be adjusted to
the highest setting during the day in order to see the
indicator lamp.
This setting is not permitted in FRONT defrost mode
and is only permitted in WINDSHIELD/FLOOR mode if
the compressor is turned on.
On hot days, open the windows to let hot air inside
escape; then close them. This helps to reduce the time
it takes for the vehicle to cool down. It also helps the
system to operate more efficiently.
For quick cool down on hot days, press the AUTO
button. The system will automatically enter the
recirculation mode where the temperature will be at the
full cold position for maximum cooling.
The air-conditioning system removes moisture from the
air, so a small amount of water dripping underneath
the vehicle while it is idling or after the engine is turned
off is normal.
Operating the climate control system in the RECIRC
mode may cause fogging of the vehicle’s windows when
the weather is cold and damp. To clear the fog, select
either WINDSHIELD/FLOOR or defrost mode and
increase the speed.
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Sensors
The solar sensor on the vehicle monitors the solar heat
and the air inside of the vehicle. This information is
used to maintain the selected temperature by regulating
adjustments to the temperature, the fan speed, and
the air delivery system. The system may also supply
cooler air to the side of the vehicle facing the sun. The
recirculation mode will also be activated, as necessary.
Do not cover the solar sensor located in the center
of the instrument panel, near the windshield, or
the system will not work properly.
Passenger Control
The arrow buttons to control the temperature on the
passenger side of the vehicle are located to the right of
the PASSENGER CONTROL window. Press the
DUAL button so that the indicator light is on. Press the
right arrow to raise the temperature and press the
left arrow to lower the temperature on the passenger
side of the vehicle.
If the indicator light below the arrows is amber this
indicates that the passenger side temperature is
set the same as the driver’s side.
If the indicator light below the arrows is red, this
indicates that the passenger side temperature is
set warmer than that of the driver’s side.
If the indicator light below the arrows is blue this
indicates that the passenger side temperature is
set cooler than that of the driver’s side.
Defogging and Defrosting
Fog on the outside of the windows is a result of high
humidity causing moisture to form and condense on the
cool window glass. This can be minimized if the
climate control system is used properly. There are two
modes to clear fog or frost from the windshield and
side windows. Use the WINDSHIELD/FLOOR mode to
clear the windows of fog or moisture and warm the
passengers. Use the defrost mode to remove fog or frost
from the windshield more quickly. For best results,
clear all snow and ice from the windshield before
defrosting.
1FRONT (Defrost):This setting brings in outside air
and directs most of the air through the defrost outlet.
Some of the air also goes to the oor vents and the side
window outlets. The indicator light on the button will
come on and WINDSHIELD will be seen on the display.
To defrost the windows quickly, press the FRONT
button, set the temperature to 90°F (32°C), select a high
fan speed, and turn the DUAL button off.
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To warm passengers while keeping the window clear,
push the AIR FLOW button to select
WINDSHIELD/FLOOR which will appear on the display.
Select a fan speed.
The air-conditioning compressor will run automatically in
this setting unless the outside temperature is below
40°F (4°C).
Do not drive the vehicle until all windows are clear.
Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog or frost from the rear window.
=REAR:Press this button to turn the rear window
defogger on or off. It will initially turn off after about
15 minutes. If it is turned on again, it will only run for
about seven and one half minutes before turning off.
Do not drive the vehicle until all the windows are clear.
Notice:Using a razor blade or sharp object to
clear the inside rear window may damage the rear
window defogger. Repairs would not be covered
by your warranty. Do not clear the inside of the rear
window with sharp objects.
Outlet Adjustment
Move the control in the
center of each air outlet to
open and close the
louvers, or adjust the
direction of the airow.
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Operation Tips
Clear away any ice, snow or leaves from the air
inlets at the base of the windshield that may
block the ow of air into the vehicle.
Use of non-GM approved hood deectors may
adversely affect the performance of the system.
Keep the path under the front seats clear of objects
to help circulate the air inside of the vehicle more
effectively.
If the vehicle has a passenger compartment air lter
and the airow seems low when the fan is at the
highest setting it may need to be replaced. For more
information, seePassenger Compartment Air
Filter on page 3-26.
Passenger Compartment Air Filter
The passenger compartment air lter is located in
the engine compartment below the air inlet grille, near
the passenger’s side windshield wiper arm.
The lter traps most of the pollen from the air entering
the air conditioning module. Like the engine’s air cleaner
lter, it may need to be changed periodically. For
information on how often to change the passenger
compartment air lter, seeScheduled Maintenance on
page 6-4.To change the passenger compartment air lter, use the
following steps:
1. Put the ignition in ACCESSORY and turn the
windshield wipers on.
2. Turn the ignition to OFF when the windshield
wipers are in the upright position.
3. Raise the hood.
4. Disconnect the windshield washer pump hose from
the fender rail and air inlet grille.
5. Remove the hood weather-strip from the
passenger’s side of the vehicle and peel it back
halfway to the center of the hood.
6. Remove the three air inlet grille retainers.
7. Remove the air inlet grille.
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