Good work so far, especially with rebuilding the MPU. I suggest upgrading to 6264 NVRAM to remove the batteries forever.

This same thing happened to mine. Did you repair the damaged traces to the solder leads of both C7 and C10 capacitors on both sides of the board? Without the LED being lit, power will not get to the LM339 parts.

The electrolyte that leaks from these electrolytic capacitors is just as bad as the alkaline leakage from alkaline batteries. In both cases it eats up traces. The burning smell was the capacitor when the electrolyte crossed between the + and - shorting out the capacitor.

Ok. Good. That is not how it read to me at 2am after a bathroom wakeup call.

I will have to review your notes again tomorrow.

My game has been working for 2 months now once I got my 12V power rail returned to the switch opto board.

You recently posted a picture which looks like the mist motor board to me. Were you calling this the 24 switch opto board?

Did you already fix this issue on that board?

Screenshot_20200930-033300_Samsung Internet (resized).jpg

I am a bit wired since waking up so I could not resist responding. Haha

That's right. It is definitely for the mist optos, not for the motor as I was originally thinking.

I think you may want to do a factory reset to clear out the error messages and retest

The C1 was the capacitor that leaked and burnt on the 7 opto board in my game. I think you should replace it as well since it will be a matter of time. When C1 leaked, it ate up part of a trace under it. I need to see if I still have pictures of it.
Screenshot_20200930-034731_Hancom Office S Viewer (resized).jpg

C2 on the power driver board is the other capacitor that likes to leak as well.

You can go higher on the voltage rating. Just remember, the higher you go, the larger the capacitor is and the lead spacing may also increase.

Guess we will see if any of it returns. Hopefully not.