I'm having an issue with the game that comes and goes. The "C" relay which energizes if a drop target and some roll over switches are hit, will randomly not energize if a target is hit. It can happen sometimes when starting a new game or while playing a game. Once a ball is in play the relay either works or it doesn't, so I'm thinking it's happening between balls in play when the machine resets the banks for the next ball. I do not have a schematic to see what other relays have switches that can control this relay.

Relay "D" (which energizes with other roll overs switches) works great and continues to work even when C is not.

I'm not having any scoring issues, if relay C is working properly then the score motor works fine.

Thanks for any suggestions!

Thank you both for the suggestions. When the C relay isn't working, there are 2 rollover switches that do not work (the 2 lower guides that feed to the flippers, all the round "targets", and all of the drop down targets.

I did check the 3 & 5 ball jones plugs, cleaned them and swapped back and forth and it doesn't make a difference.

Couldn't see any visible loose or poorly connected wires leading to any drop targets, but since there are other targets affected as well I'm questioning whether the drop targets are the issue.

I'm going to look at the score motor. Since it seems to start after a ball drains and the motor scores earned points, perhaps a sequence isn't completed- rendering the C relay dead during the next ball. I've checked the switches already but may give it another look. I'm grabbing at straws now since I've looked everywhere else I know to try.

Thanks again

Right you are Mark, without the schematic I had incorrectly assigned those targets to the same C relay. I cleaned and checked the score motor switches quite thoroughly. Looks like all the non-drop down targets (bumpers,rollovers,etc) are scoring properly now. Only the drop targets are not scoring, so I'm not sure what could still be out of whack.

Somewhere in my adjustments of the relays I tweaked something because the ball won't eject upon game startup, and the machine won't advance past Ball 1.

1 step forward & 2 back.

Thanks for all the assistance. The problem here was indeed in switch stack 1 of the score motor, as noted on the schematic. It's a difficult set of switches to get to (rather buried in the cams and I must have missed them when I adjusted everything earlier), but once adjusted it works great. Appreciate all the help.