Hello,
Maybe someone here can help troubleshoot this because I don’t know what to try next. I had been having intermittent problems with opto switch 84 (Lock middle). At first I thought it may have been dirty since this game was filthy years ago when I got it, so I pulled the whole thing and cleaned it. After putting everything back together it worked for a few games and then closed again. I tried cleaning again with a cotton swab while in the switch test and when touching the opto, it came back for a little while then went back out again. I figured maybe this opto was bad so I decided to replace both the middle and upper opto while I was there. After the replacement the same problem exists. I tried reseating plugs, checking for loose wires, nothing I could come up with to trigger that opto. Anyone have any ideas of other things I could check with this? All other optos work fine.
The giveaway to this switch not working is apparent right when you turn the machine on. The pop eject back near those switches trying popping a couple times since it thinks a ball is in the location of this opto. This then causes problems if you try playing with two balls ejecting at certain times.