My Hotpoint wd420 showing error f12: No communication between cards.
I have changed both boards (Pcb and one in the bottem) but still showing the same fault. machine will not stop filling and the dryer heater element keeps heating up. no fan, just heat. is there anything else i can do or check. does anybody have a wiring diagram?
Cheers Amar

Amar, June 2009

If it keeps filling (overfilling?) and heater comes on - have you checked and cleaned the pressure vessel, the tube to pressure switch and the switch itself.

Phil, August 2009