So, I'll start this off by saying that I've cleaned and rebuilt a board that had major battery damage. More as a learning process than anything else. Every component on the lower half of the board was removed, battery damage was neutralized, traces cleaned and repaired. I just got everything installed again with new parts and I'm getting an error 7.

After I push the button, I'll get a 1, but sometimes a 6. 6 isn't even listed anywhere.

I've got a logic probe on hand, and I'm ready to learn if someone wants to help me diagnose the issues that I'm having.

Roms are swapped from a known good board and the sound test works fine.

Thanks. I've been going through a bunch of the old threads, and the williams troubleshooting guide.
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12V and 5V are both good.

I don't see a one second low followed by a constant high on pin 40. It's always high when i turn the game on. Tried on 2 known good chips.

All socketed connections have confirmed continuity from chip pin to solder joint on the back of the board.

Pin 21 of U17 is low and not pulsing.

Bump. Still looking for some help. Or a swift kick in the right direction.

Pin 21 just goes to ground. All 39 traces from U17 have continuity to the corresponding parts. Just checked and confirmed each one.

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