Klarstein Mundschenk power settings

[clarets7]

Traced it through, two lines coming direct from the N76E003AT20 on the display board, P700 and P1800, go to the relay board via the ribbon then to a single transistor for each relay, no other lines to those. Something strange going on inside the micro - and it definitely used to work. On the faulty board it just switches both relays on whatever the power setting, but will switch them both off when it hits temperature. It's as if the power setting part of the program is no longer talking to those lines.

[MashBag]

That does sound like internal chip failure.