Ford 1998 Crown Victoria Owner's Manual page 25

Controls and features
The defroster turns off automatically after 10 minutes or when the
ignition is turned to the OFF position. To manually turn off the defroster
before ten minutes have passed, push the control again.
CLIMATE CONTROL SYSTEM
Manual heating and air conditioning system (if equipped)
LO
VENT
MIX
HI
Fan speed control
Controls the volume of air circulated
LO
in the vehicle.
HI
Temperature control knob
Controls the temperature of the
airflow inside the vehicle.
Mode selector control
Controls the direction of the airflow
VENT
to the inside of the vehicle.
MIX
The air conditioning compressor will operate in all modes except VENT
and FLR. However, the air conditioning will only function if the outside
temperature is about 10°C (50°F) or above.
Since the air conditioner removes considerable moisture from the air
during operation, it is normal if clear water drips on the ground under
the air conditioner drain while the system is working and even after you
have stopped the vehicle.
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