Weird problem- Kick out, ball return and Z drop target on same circuit often do not respond. Sometimes if I bang on the side of the back box they immediately start working. Have checked switches, wiring, harness plug on driver board and when I have run diagnostics all solenoids fire as expected. One time when I left the ball sit in the kick out hole for about a minute without doing anything else it then all of the sudden kicked out as expected and then everything worked fine for remainder of that game. Next time I started a game, same problem occurred but leaving the ball in the kick out for a couple minutes did not make a difference. Seems to be an inconsistent issue, sometimes working fine, sometimes not working. Any suggestions as to what may be causing this issue or ideas that I might try to resolve this issue? It only happen on the one circuit, all other solenoids on other circuits are working fine.

Thank you for your reply. I had thought it had something to do with connections someplace. I also have the schematics but I know nothing about how to read them. lol I will try your suggestion and maybe that will help me figure out where the problem exists. I had run a diagnostic test on the solenoids and they all fired normally. I could also run a diagnostic on the switches too. I know for certain the both the eject and outhole both go out together and possibly the "N" drop target. Again, thank you very much for your reply and suggestion which I will try now.

Thank you so much for your suggestion!! I was able to trace the problem to the switch column drive on the Driver Board. Not quite sure how to permanently repair it but when the eject and out hole do not work, I just barely touch the wires going into the plug that goes into the board and that immediately fixes the problem. I will try maybe putting black tape on the wire holding them a little tighter to the plug. But thank you again because I was thinking I might have to either purchase another driver board or send my board to someone who repairs them. You saved me a bunch of money!!

Thank you for the reply and the links to some great and helpful information!!

It appears that I will need to do some work to the connector pins. I've gotten good advice and help from you and the other replies. Thank you very much!!