I have a Baywatch that has experienced battery damage. Someone has resocketed the blanking processor and the only other place I saw significant corrosion was the battery holder. It wasn’t keeping memory consistently so I bought NVRAM and it was playing fine for a handful of games. While playing it spazzed out and the DMD went blank, never to boot again. 5V and PIA LEDs would stay lit but no blanking, voltages all checked out.

I pulled the driver board and found some super nasty corrosion under C89. Replaced that cap and now it was starting to boot but going into a weird switch test screen automatically and not allowing me to move past it. I removed the NVRAM and put the original ram back in and installed a remote battery holder. Now it boots partially, but stops at the “OPEN COIN DOOR” screen. I’m getting correct voltage from the holder, diodes are good, and the B+ test point has 4.3vdc. The relay on the PPB clicks when I open and close the door and the GI comes on and off but the DMD never says anything but “OPEN COIN DOOR”.

Seems like a memory circuit problem but I’m not sure what else to check, has anyone ever encountered the problem where you can’t move past this screen?