CPS color repair question

[Solmin]

My buddy has a Tower of Doom board but white doesn't show up in the color test. Is there chip or something he can swap out?

 

[nem]

Not sure how that's possible? Is the color test showing red, green and blue? White is just a combination of these three.

 

[Solmin]

Color bar and other image is from D&D
Ryu is from SF which color comes out correctly. So not sure what is wrong with the board

 

[nem]

Your blue output is the problem. Looks like your missing half of the gradients. Naturally this will affect white as well, because R+G+B=W.

I don't think your SF is working correctly either. You should notice it on any light blue that is either too dark or too bright.