Blower motor stuck on one speed and won't shut off

I'm working on a 06 mitsubishi galant LS 3.8L. The Blower motor only has one speed and will not turn off. The AC button alluminates when you press it and all the other cold/hot and vent mode dials work. I already replaced the blower motor resistor behind the glovebox. I was thinking it might be the blower speed control head unit/dial on the dash but they are very expensive and I would hate to throw that part at it and not fix it. Any other ideas on what this could be?

Thanks,

Russ

What speed does it work on? The highest, lowest, or in between?