Status: Successfully Repaired on 4/16/2022
In for repair was a Namco Outfoxies arcade board.
The game booted up and played fine with one player, but in two player mode Left, Down, and Button 1 wouldn’t work for Player 2.
Tracing the Player 2 control signals from the JAMMA connector, I discovered that they stopped almost immediately at a ceramic EFI filter close to the JAMMA edge. The filter had a crack running through it, disrupting the circuits.
The ceramic part separated completely when I desoldered it from the board.
A replacement part is hard to source these days, but fortunately the Outfoxies main PCB has an extension connector for Player 3 and Player 4 on the board edge that Outfoxies doesn’t use since it’s only a 2 player game. Therefore, I moved one of the unused filter parts from the FL3 position on the P3 & P4 connector over to the main JAMMA connector and all the Player 2 controls now function properly.
Namco boards that use surface-mounted capacitors are also notorious for having those caps leak, so I also replaced all the electrolytic capacitors on the board.