hi am engineer an tryin fix this dw fills up washes heats then near end prog starts flashing 4 times . shud be pressure switch chocked took it off cleaned it still same then thoght it maybe broken took it apart an wee micro switch inside is readin owt ok so dont no weather to replace part or not?
If you are certain that the switch/diaphragm mechanism is working and it does actually drain, the only other possibilities are wiring or the pcb.
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