I have a DWF415 Ikea dishwasher from Whirlpool. It has started giving an f4 error, the start led blinks 4 cycles. Sometimes the machine gets to the end of its cycle before showing the error, but more frequently it will now stop mid cycle. I have checked the waste is being pumped out OK, it seems to be unrestricted flow and all filters are clean.
Any help would be appreciated