So I diagnosed my Data East Simpsons as having a bad EPROM. I looked at the DE repair wiki and my problem matches up exactly what they describe as a bad EPROM at “5c and or 5b”. I have a Rottendog board. In the manual and online they show the Simpsons as having an EPROM at both 5b and 5c but my board just has one at 5c. It has worked fine for almost 3 years.
I ordered the EPROM set from Marco as I needed a few other parts for other games. When it gets here do I just put in both EPROMs or so I need to do something to the board.
The current EPROM that went bad was from Ks arcade and they sell just the 5c that they say works instead of having both but then they talk about stuff being jumpered, no idea what that means.
Any insight would be appreciated, thanks

Here are some pictures, I don’t know what the rom size is for the current one. I have not had any rom issues before so I don’t really know anything about them yet.
At B5 on the board it says 28k with J4 blank with J5
At C5 it says 256kk with J4 512k with J5.

I bought the B5 and C5 game Roms from Marco, they were $10 each.
Thanks Athens95 for the reply

To clarify the rom in the picture is the one that went bad, the two from Marco are on the way in the mail.

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Looks like I will have some time to figure it out. Should have been here today, paid a little extra for priority but the post office as usual is way behind, they don’t even know when it’s going to arrive now, hopefully they haven’t lost it.

So an update in case anyone else finds themselves in a similar situation. EPROMs arrived. There was a zero ohm resistor (one single black band in the middle) at J5 and J4 had nothing. I unsoldered the zero ohm resistor at J5 and soldered it back on at J4. Put both EPROM chips in and the game works again!