I picked up a Mr. and Mrs pinball project and my last big issue is the displays. In test mode, the displays cycle through the numbers as they should. When I start a game it shows the leading digit as 0 and then a comma and then the score is at the end. It does keep score properly but has the 0, in the beginning, which I know isn't right. The fourth player display flickers all kinds of numbers during the game.

I unplugged all the plugs that are connected directly to the back of each display and had no change in results. Where do these connect in the head of the machine? I looked at some schematics and it looks like these connect at J1 main CPU. I'm going to look at that next. Does anyone else have any ideas what could be causing this? Any help greatly appreciated.

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There is a pinball God! I removed all the displays in the machine and started putting them in one at a time to see if I could narrow down what display may be causing the problem. I also started with the displays that looked to be good. At any rate after moving the order all around, the displays started functioning correctly. The leading zero with the comma after it went away. The comma after the credits also corrected as well. So, I'm not really sure what the problem was. The display in the four-player position is missing a segment in it. I tried soldering the opposite side of the connector on the display and had no change in the missing segment. I may take that display out again and try soldering where the connector pins are on the display board. Maybe I will get lucky with that. I feel a little pac-man fever coming on.

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Thanks for that info. I wasn’t even paying attention to that.