We had a fleet of Ford crown Vic's years back at our taxi company. I drove one that the fan had only low and high. It was missing the second and third position. Mechanic changed resistor, brought back all 4. But as stamp said it was a basic manual setup. Those worked the best. The full automatic ones were always trouble, rarely worked right. Glad yours was an easy fix. Sometimes you got to plug and play, if you don't have the testing ability.
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