So I got this DM. Game worked fine. Shopped it, put in LED's, replaced the big caps and bridge rectifiers on the driver board. Plug everything back together, game boots fine, but NONE of the switches work, can't start a game! Even the service buttons on the J205 direct switches don't work.
I noticed F105 was dead and replaced it, the schematics say its for "HI POWER PULSE", doesn't blow anymore. Coin door interface board/connectors looks good.
I forgot I shouldn't be installing LED's with the game on. Looking at the schematic, it appears I may have blown U16-19, LM339's which apparently go bad. New LM339's are on their way. U13 and U15 could be blown also but figure U16-19 is a good place to start. Game is at my brothers and I just discovered this today, haven't had time to bust out the logic probe yet.
This sounds like it may be a stupid problem and I'm just not seeing something obvious - anything I'm missing?