CPS2 A-Board Colour Issue

[nnap]

I have an asia region a-board that developed a colour issue. The game plays fine but the colors are all mixed up. You can see it in the color bar screen. Any sugestions on what to change on the board? I replaced most of the ram and a couple of the TTLs.

 

[Raph_friend]

Did you check my articles about A boards?

 

[nnap]

yes, I read it. That was the source for the TTLs that I already changed. So far I have replace these:

LS157 @ 7U, 7V, 7W
LS07 @ 8B, 1D, 1E, 2E
MB8464A @ 2L
MD81C78A @ 4D, 5D
HM658128 @ 13R, 14R
HM514260 @ 13V, 14V

there are a couple of additional LS157 above the DL-0921 custom that I might try next (2T-2W, 3T-3W).

 

[Raph_friend]

The problem is around the palette circuit, worst case, the DL custom.

 

[nnap]

quick update. Pulled the B-21 from a working C-Board and replaced it on the CPS2 A-Board. Still the same behaviour.

Now that I look at the board, I am not sure if I replaced the palette ram @ 4D, 5D. Will order some and replace them.
From the schematics, the LS245s @ 4H & 5H are also involved. The PAL @ 7S also. More stuff to check then

 

[Apocalypse]

I had something similar and it was the DL-1625.
Could also be the DL-2227 I guess.