I had a Color DMD in the machine but wanted to swap the color into a different pin. I loosely connected an old display and it was working. Once I properly installed the old display it blew the 5V logic fuse. I'm not sure what I did wrong but I must have got a cable backwards or shorted something. I reconnected everything and replaced the fuse and the fuse holds but I can't get anything out of the display. I tested all voltages at all the connectors to the display and display board and everything appears good. Just to try and eliminate possible issues I hooked up a new 5V DMD and avoided the high voltage. I tried different ribbon cables. I bought a logic probe , I thought maybe there was a problem at U201 or U202 so I had those replaced. Still no luck and I'm out of ideas. If I could even narrow the issue from CPU to Display board that would be a huge help.