Bosch Ascenta drains and won't start cycle - even when dry
I have a Bosch Ascenta dishwasher (SHE3 ARL5UC) that start a cycle — it just runs the drain pump twice and then says clean after you start it. This happens even if the bottom of the sump is completely dry and there is no water in the machine. There is a workaround: if you open the dishwasher during the second draining, then close it again, the dishwasher runs as normal.
I don’t think there is anything wrong with the drain pump itself or the check valve. It drains fine, though it also seems to drain a number of times at the end of the cycle (but it sounds like it is running dry after the first time). The same symptoms happen even with the hose from the outlet of the drain pump disconnected (in which case it is certainly draining fine). I have cleaned the drain pump impeller, the inlet to the pump, the check valve, etc.
Basically, I think the machine drains fine, but for some reason it doesn’t think it is draining properly and thus won’t start the cycle (unless you open the door). Seems like this is not an uncommon problem, but I don’t see anyone has found a solution. It seems like the problem could either be the control board or perhaps the circulation pump (which I understand functions as the water level sensor), but I’m hesitant to start replacing expensive parts without knowing what the problem actually is.
Is dit een goede vraag?