System Air Flow Description - Manual Climate Control: Defrost

WARNING: This page is about a different car, the 2003 Mercury Marauder, 2003 Mercury Grand Marquis, and 2003 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.

When DEFROST is selected:

The air inlet door vacuum control motor is at no vacuum, admitting only outside air into the passenger compartment.
The floor/defrost door vacuum control motor and the panel door vacuum control motors are at no vacuum, directing airflow to the defroster duct and the side window demisters.
The temperature can be adjusted to heat or cool the air below the outside temperature.
The A/C compressor will operate if the outside air temperature is above approximately 4°C (39°F).
The blower motor is on.