I'm working on a Williams A-Go-Go and one problem I'm trying to resolve now is that when I'm in a 2, 3, or 4 player game, the player unit doesn't want to reset back to player one after draining ball #1 of the last player. In other words, for a 2 player game, when ball #1 drains for player 2, it does not reset the player unit to player 1, and it does not advance to ball #2. Instead, it advances the player to player 3 (even while in a 2 player game) and continues with ball #1. Likewise, for a 3 player game, when ball #1 drains for player 3, it does not reset the player unit to player 1, and it does not advance to ball #2. Instead, it advances the player to player 4 (even while in a 3 player game) and continues with ball #1. Same thing for a 4 player game.
Observing the player reset solenoid while someone else plays the game, I don't see it attempting to energize when it should be resetting back to player 1 after draining the ball for player 2,3 or 4 (for a 2,3, or 4 player game). However, if I shut the game down while on player 2, 3 or 4, and then restart a game, it will reset the player unit back to player 1. So, that tells me the player reset solenoid is working, but it's just not being told to reset at the end of the a ball for a 2, 3, or 4, player game. I'm thinking there is a switch not making contact in the coin unit, but I'm having a hard time chasing this down in the schematic (file:///D:/Williams_1966_A_Go_Go_Schematic_Diagram_continuous.pdf). If not that, what else could it be?
Any tips?