Simpsons Graphics Problems

zz0ljf

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I've purchased a Simpsons PCB that is having graphics glitches. All of the playable characters and enemies are only partially displayed. I've run the RAM / ROM tests and everything tests out OK. +5V must also be good as I'm running this PCB in my TMNT cab that works fine. Anyone got any ideas on what IC may be bad? One of the Konami 005273 components at S31 look like someone attempted a repair with some resistors soldered in place. Not sure what these components are for. I'm presuming they are custom resistors. I've reseated all the socketed chips, one chip had a leg out of the socket touching another chip and one of the CPU chips had a bent leg that I straighten but it didn't appear to be touching any other legs. I don't see any broken traces. Any help would be appreciated.
 
It also appears that the IC at 9C has been replaced (poorly). Not sure what this chip is and where I could find a replacement.
 
What are the #s on the chip?

What tests did you run? There are 2 different tests for that board: Power on tests and ROM tests you run from the test menu. The ROM test from the test menu is the only test that will check the graphics ROMs on a Simpson's board.

RJ
 
The number on the chip that has been replaced is HD74LS257P.

As for the tests, when the game boots up it runs the RAM ROM test. This passes 100%. I then used the service button in my TMNT cabinet to get into the service menu where I ran the ROM test. This one also passes 100%. I tried pressing the "TEST" button on the PCB but nothing happened. Not sure if I needed to depress it while powering on the game or something. Is the "TEST" button on the PCB designed to take you to the same service screen I got to by using the service button in the cab or are the diagnostics different?
 
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