After cleaning my IIc board, I get this issue. I swapped the rom, cpu, mmu, iou from this board to another and it all works. The issue is related to this board and/or items on the board. I don’t get to test screen. It worked before the good cleaning. First time with brush and IPA only delicate brushing then one with ultrasonic cleaner and a few hours In the sun after a good IPA rinse. I don’t have RAM to try and this the 4100 series uses only 4 ram HM50464p-15. Anyone any ideas as I am out of ideas
