Lincoln 1997 Town Car Owner's Manual page 65

When you move the thumbwheel, the fan speed
will go to manual control. The display window will
show the H symbol in the upper left corner along
with the selected temperature and operating
function.
You can override the fan speed at any time. If you
use the thumbwheel to override the fan speed, the
EATC will continue to control the temperature but
you control the fan speed. To return to auto fan
control, press the AUTOMATIC button. If you are
operating in one of the override functions (FLOOR,
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