Buick 2004 Century Owner's Manual page 124

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 floor 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.
3-22
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.
9
FAN: 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 airflow seems low when the fan is at the highest
setting, the passenger compartment air filter, if
equipped, may need to be replaced. For more
information see Passenger Compartment Air Filter on
page 3-26 and Scheduled Maintenance on page 6-4.
AIR FLOW: This control has several settings to
control the direction of airflow 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.