Quoted from josh0:I think the problem is in the attached portion of the schematic player reset relay and ball count step up both fire when adding either extra ball
The Player Reset Relay and Ball Count Unit would step up together..
It seems either Score Motor switches 3A or 8A are hot all, or at least much of the time.
My first guess would be it's the 8A set of switches.
After start up, start the Score Motor's revolution by hand, and check if it energizes the Ball Count
Step Up? If so, consentrate if it's the 8A or 3A set of switches when making and then carefully inspect
that area..