I've got 6 switches (#'s 21, 25, 39, 45, 53, 61) that are not registering when closed. There is no common row or column that they are on. I have tested the actual switches involved and they are good. I'm at a loss as to what I should be looking for. Any help/suggestions are appreciated.

Thanks. Have re-seated the connectors and the switches are still not working. Have also checked the continuity on both the ground and power lines and all is good there as well.

Thanks, Mark. I played around with #39 and found that it worked intermittently. Went ahead and replaced it and the new switch works 100%. Going to try and do that with #25 as well but it's a bear to get at. It's the sword ramp entrance switch and if I remember correctly I've got to take that ramp off to even get to that one.

I recognized the "row" correlation on those 4 switches as well. Digging a little deeper, I've now found that switch #13 is not working either. It's on that same row as well so now there are 5 switches on that row that are not functioning. Again, I jumped power to that switch from a working switch and it worked so I know it's not a bad switch. None of the "bad" switches are optos.

Typically I would think there's a board component (transistor?) that's bad. However, the other two switches on that row, #29 & #37 are working. There should be another on that row, #5, center coin slot. However, my machine only has two coin slots which are switches #4 & #6. There is no #5 on my machine. Does anyone know if a transistor can be partially bad, letting some switches work but not others?

That was my thought too so I tore the sword ramp apart to test #25. It was wired backwards. Now fixed and working as it should. There's a reason I call myself Pindufus.......

That leaves me with #'s 13, 21, 45, 53 & 61 not working. All are in the same row.

That certainly would explain why 29 & 37 are still working. Tomorrow I'll start looking at the wires more closely and maybe even add some solder to make sure the connections are good.

Thanks Pin Guy and everyone else providing assistance.

Thanks guys. Found the loose wire. Did a quick solder job and my game is back up and running.