The knob for the fan control only works on the highest number.
on 2010 Ford Escape

Just started happening, i do have automatic on this vehicle so i dont know if it matters. Heat only works on highest setting.

2 answers 2 comments
Possibly the blower motor speed control, on the heater box above the blower motor.
I had the same problem on another car. It was the blower motor relay... it's a possibility that it's the same problem. Wasn't too expensive for the part, and I replaced it myself.
It's called the blower motor speed control on this model as posted.
What is it with snotty people on this website? I am happy you felt you had to correct me.