Looking for ideas here. I have one of the craziest and most difficult issue, I have ever seen. None of it makes any sense.
Problem:
Game resets when 3 events happen.
1. You try to add more than one player
2. You go past setting 5 in diagnostics/audits/settings
3. You lock 2 balls and hit one of the 2 entry switches that starts multiball
Here's what i've done:
Aquired images of the ROMs from a known working game
Swapped CPU boards
Swapped Driver boards
Disconnected the sound board
Swapped Ribbon cable between CPU and driver board
ran switch and coil tests extensively.
Tested all diodes
When the watchdog circuit is overridden after the game is powered up. Everything works like it should. You can add mutiple players, you can start multiball, you can do all the audits, diagnostics and settings. This worked with both CPU boards which was tested and fully working. Also, i have recently tracked down a manual for this game (took awhile) and there are not alterations done to the Zaccaria Gen 2 boards. All standard boards except the sound board, which is special to this game. I thought for sure my ROMs were corrupt, so now I have no idea. Strangest problem i've ever encountered.
SOLVED!!!!!
turns out, that for this game. To compensate for shitty coding. They decided that the MPU board needed TP7 (watchdog override) to be jumpered. It has 2 pads for the same TP. Jumpering these 2 pads together, overides the watchdog circuit. Which this game needs to run properly. And doesn't say anywhere in the manual.