I am repairing a 1973 Bally Nip-It machine and have run into a few problems I can't figure out. Here are the issues I'm having:
1) The bonus is never counted when a ball drains.
2) The "gator ball" never locks. Instead it runs the score motor for a few cycles, awards points, and kicks out instead of staying locked.
3) The game never resets to player 1 during multiplayer. It will advance to player 2, 3 and 4, but never return to 1.
I've done the usual stuff - heavy cleaning on all jones plugs, stepper units have been taken apart and cleaned. All stepper unit eos switches have been adjusted and tested for good continuity. I did a general cleaning of a wire brush on every relay, but didn't go through them 100% individually. I also did not clean every contact on the score motor yet, but did do a thorough check on cams 1, 3, 4, and 6 as I was repairing other issues.
I've noticed what may be a short in 2 of the relays. On both the "player reset relay" and "2nd ball relay" there are sets of alternating contacts toward the rear most side of the fixture (middle contact moves to touch a different contact on either side when coil is energized). I've noticed that in either position (solenoid on or off) that all 3 contacts have continuity between them, despite the center contact clearly not touching both of the other contacts at the same time. Could someone tell me if this is normal or if I need to hunt down a short somewhere?
Any other help is appreciated. Thanks!