My tech buddy is working on my Farfalla, and I share his questions and his observations below.
First: Does anyone know what this small brown board is? It looks like something that was added after production, and my guy says it's not in the standard schematics. He wants to remove it, but I've asked him to hold off until we figure out what it is, and what it is for.
"Having problems with switches. Credit button thinks it's diagnostic switch, so wont start a game. rewired coin door and rang out wiring to cpu board. Missing signals on switch row 2 and 3. I would be able to fix ( IC38 suspect) but this game has some alien circuit board (see picture) that's tied into the switch circuit. I haven't a clue what this thing does. Look at the picture, and the top of the AC looks green with acid damage. Do You know the Zaccaria guru and ask about this little board? Everything else, lamps , solenoids and displays work perfectly, those little lane flippers work in test too."