The flipper circuit is pretty simple. There's a big relay on the left of the driver board that pulls in and provides ground to the flippers when a game is started. There's the cabinet switches. The coils, diodes, and EoS switches on the playfield, and a fuse.

First, start with the obvious and make sure the under playfield fuse for the flippers is there, has continuity through its holder, etc. It's probably not the fuse, but it's the easiest place to begin. Since you really only tinkered with the boards, I'd move on to reseating the connector at 2J12. That's the second one from the top, on the left of the driver board. Its bottom two pins connect the flipper to ground through the big relay. If the connector isn't the issue, make sure the relay isn't loose on the board. It should definitely have its solder reflowed if it hasn't been already. Check to see if the relay engages when a game starts. It should pull closed with a click.

If that's not the issue, check the connectors in the cabinet 8J/8P and 7J/7P to ensure their firmly connected. Make sure the flipper switches are clean, not pitted, and that they're making good contact when you push them.

It'd be odd for both flipper coils, diodes, or EoS switches to go bad at once, but that'd be the next place to go if none of the above helps.

hot tip schematic flippers.png

I'm glad you were able to find the problem and get it going. Sorry that I didn't suggest checking that wire first. It's right there in the schematic where it says, "To Bridge Rectifier" and has only one connector pin. It didn't occur to me that it might have been unplugged when moving the boards, so I didn't even mention it. My fault.

It can be a pain troubleshooting games, but you have to admit it's satisfying when you figure it out.

Yep, the< < is a connection. The number in between says which pin on the connector it is. The bigger blocks have squares around all the pins on the same connection with labels above them, like 2j12 is the jack on the board and 2p12 is the plug that goes to that jack.