I have a Mr/Mrs Pacman I have been working on. The player 3 display is showing "99" instead of "00" in single player mode, and "999999" when you do a 4-player multiplayer game. Here is what I have done so far:

Inspected J1 on the MPU and tested the pins for continuity back to the board. They were previously reflowed. Also checked for closed circuits between all of those pins. I also checked traces and rung P20-24 back to U20. The resistors and diodes between those two points check out okay as well.

The display itself looks to be in good shape, no cold joints on the connector, and nothing is burnt anywhere.

What would be my next step? Checking wiring continuity? Checking for a bad IC in U20?

Thanks!

The other displays function fine. The machine is at another location, but I will try switching displays tomorrow when I go back.

Okay, well the problem followed the display... So I guess that narrows it down. Overall, the display looks to be in very good condition. Nothing burnt and no cold joints.

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The far right two digits are always "00" or "99", the rest of the positions are blank.

I forgot that in game mode, the score reads all digits as "9", all the time.

Forgot to follow up on this... The problem wound up being being the IC on the individual display itself. Resocketed and replaced the chip... All good now. Thanks everyone!