Quoted from Dellamarmalade:Ok so I've ordered the board and waiting on it to come. Where do I find the flipper opto board on the machine and should I order it as well just in case the mini playfield opto doesn't work.
The flipper opto board is the one that you activate by pressing the flipper button - it is screwed to the cabinet on the inside of the flipper button.
You could try cleaning the opto slots in the optos on this board with a cotton bud, this might fix your problem and is easy to do.