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Sunday 27 May 2018 at 11:19
Does the coin unit step up to 2,3 and four players?
If the ball in play doesn't increase, look at the ball index relay for a misadjusted or dirty contact.
A way of testing is to tilt the ball in play, if it gets to the second ball it is surely the ball index.
If the coin unit does not step up it is ...
Source: http://pinside.com/pinball/forum/topic/bally-wizard-only-works-on-one-player#post-4420823