Here's something I found interesting. And not related to the DMD. The top half of my backbox GI lights are all off, so I traced the lights' wires back to the PPB (Playfield Power Board), and started checking the fuses on it. (Obviously, I replaced a couple bulbs first, to no avail.)
Oh, and another issue that has been baffling me is that on power up, Frank says, "Frankenstei-" and the end of the word is cut off, and then there's silence for awhile, or until a game is started.
Back to the PPB fuses: F6 was too large a value, so I replaced it with the correct one. That shouldn't change anything, just make it more safe. F4 was correct, and tested fine, but it looked a little grungy, so I cleaned the contacts, and put in a new fuse. All the other fuses were fine.
I also reseated the J6 connector, which is near the fuses.
Well, none of this fixed any lights, but when I powered Frank back up, he said, "Frankenstein!" (the whole word), and then some music I've never heard before started playing, where once there was silence.
I'm no schematics expert, but I can't see any connection between the PPB and the sound board. Any ideas about what happened here?