I've read plenty of posts about the problematic Sega Large DMDs. I have a Frankenstein with a completely dark DMD. No flicker, no sign of life, no nothing. I measured the voltage at the 5V connector on the controller board and it is 4.97 volts. I reflowed the pins on the PS and the controller board.. I do get 5 volts at the PS. I have 4.97 volts to the 5 volt and 17 volts to the 18 volt side of the DMD power connector.

I also tested by using an atx power supply that is sending 5.1 volts to the controller and DMD to see if the slightly low 4.97 was causing the controller to not boot. Nothing has made a difference. Not sure of the 17 volts is too low to drive the DMD? I would have at least expected to see something appear on the DMD at startup or even during a game.

I've cleaned pins and reseated data ribbons, removed and reseated display roms....nothing.

At this point, how do I tell whether the DMD is bad or the controller is bad or both? Anyone local in CT have a large Sega DMD game that I can test my components in?

Thanks,
Russ