it could be anything at fault causing it.faulty drain pump,faulty circ pump,not filling to set level,heater fault,temp sensor fault or blockage in the iwms.pcbs do fail but you need to be sure the rest of the components are ok before putting a new pcb in because if there is a faulty component it could blow the new pcb and it will be your fault with no refund!.as you look at the appliance from the front,remove the lefthand side panel and check if the iwms is all blocked with black mould.
ck, January 2009