Buick 2004 Century - Manual (Page 127)

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 airflow.
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