Honda Element AC/Heat control malfunction.

Having an issue with the AC/Heater control. Took my Element to the Honda dealership for a Passenger side airbag recall and Driver’s side seat belt replacement. When I picked the car up the AC fan nothing would come on the dealership claims the went nowhere near the control that it just failed while there for service they want to charge me 765.00 to repair it. I went to the back with the mechanic and he pulled the wiring harnesses plug almost all the way off the pins and it works. Anyone seen this before?