Could I put the TW MDB in and see if that helps?

Peter

I'd advise others who may be reading this thread to use some caution when swapping WMS display bits around like this between machines - not all have all the 100V supplies fed to the actual displays - in Peters' picture you can see the single brown wire in a connector that is angled off at about 11 o'clock sort of behind the leftmost top (P3) connector. On machines that have it, this wire is fed into the harness that connects to the player displays. I have a set of WMS displays that  do not have this feed.  I'm not sure of the effect of putting one of these displays onto a master board with the extra feed?   Does anybody have knowledge on this?  There is also a comment on the board layout drawing mentioned above about this extra fed, but it's a bit cryptic to me.