Outrunners Repair: cannot access Test Menu and graphical errors

[Casselfornia]

Hi,

as seen above: I got that PCB from Italy. Came covered in dirt and rat shit. PCB looked grimy but surprisingly good. After replacing the mask rom ic36 it came back to life.

The rom board now definitely works, as I checked it on another mainboard and it run great.

I cleaned the PCB with isopropanol and let it dry. Main problem is that I cannot see the font in the test menu. I attached pics, any advice? I have a logic probe/multimeter and a bit of experience but I don't know where to start on this one.

 

[stj]

if it had rodent piss on it your in for a lot of work.
but first - pull all the roms and if your programmer can check them, any socketed ram
check as many chips as possible off the boards

 

[Casselfornia]

ROMs on the romboard are all okay. There's no socketed ram on the mainboard. So I assume I have to desolder. That's quite a lot. I'll try it tho.