That control is expensive ,but you can buy cheaper off ebay , if you look for it .and it is a common issue, just make sure the connector to is good also not melted or evidence of burned spots ,
you can take it apart and look at circuit board for any bad spots, i guess i can try to repair it , if you know a computer guy that knows how repair the board .
but that is one way you can confirm .
i sent you the wiring diagram of the controller , pull it out of dash, back probe all 4 wires , DB/YL , DB/VT , DB/OR , DB/ BR going to the blower motor resistor
what are you reading if any
please let me know if that work for you , or you need further assistance
ASE Certified Technician