I was trying to fix the transformer because it was very noisy. So I have tightened some nuts and I have given a couple of blows with a rubber hammer to demagnetize it. Now, when I turn on the pinball the CPU board does not do anything showing all the LEDs off (D19, D20, D21). I have checked all the fuses and all of them are working.
Could any of you tell me what is going on?