System Airflow Description - Electronic Manual Temperature Control (EMTC): Defrost

WARNING: This page is about a different car, the 2013 Ford Mustang. However, it is still accessible from the selected car via links, so may be relevant.

When DEFROST is selected:

the air inlet door actuator opens, admitting only outside air into the passenger compartment.
the mode doors direct airflow to the defroster duct and side window demisters. A small amount of airflow from the floor duct will be present.
blended air temperature is available.
the A/C request button will indicate the last status and the indicator can be toggled. To reduce fogging, the A/C compressor will operate automatically, regardless of indicator status, if the outside temperature is above approximately 6°C (43°F).
the blower motor is ON.