Hi, over the weekend we are having the same problem with our NEFF dishwasher. I took the side off and worked out it was the antiflood device but I can’t find a leak YET. My question is though why did you also ask about the 3 or 4 in 1 tablets as we do use them.
is there water in the base ? If not , then sometimes the anti-flood float (red ‘can’ looking device ) can be lifted if theres gunge in the pressure chamber that it sits in. water gets trapped in it and lifts the float …also , mice chewing on the polystyrene disc in the base can cause probs