I have an 02 ML320 in Louisiana. Whether my AC Fan motor is high or low I am getting a constant flow of air from the defrost vents on the dash. Of course in Louisiana we are plagued by humidity and this airflow causes my windshield to fog over all the time.

Can anyone shed some light on my airflow issue???

There are electric motors that move flaps to change the air flow.
Most likely there is an issue with at least one of those motors.

Code reading with MB scanner is needed.

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