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Thursday 12 April 2018 at 12:10
You don’t need to replace the board, just the transistor that controls that coil (a couple of bucks max). Requires basic soldering skill and the manual/ability to test the transistors with a meter. That said, the advice above is great.
Source: http://pinside.com/pinball/forum/topic/negative-positive-side-of-a-coil#post-4334534