MVS MV1-A vertical lines

[copados33]

I have this MV1- "A"? motherboard which recently has developed this issue where some vertical lines are missing from the image, it only appears on texts and certain ingame graphics, I have checked the cartridge slot for cold solder joints but that doesn't seem to be problem here as the issue is present even without any game inserted:

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I can solder (I have a hot air desoldering gun) and I know how to use a multimeter and maybe a logic probe, so maybe someone knowledgeable on the subject might point me out on what I should start to look and what part to touch/replace?

[leonardoliveira]

One of the data lines for the FIX ROM (S-FIX and S1 on cart) is severed. Sprites (C-ROMs) are fine.
These are input to pins of the FIX at the chip NEO-GRC.

https://wiki.neogeodev.org/images/c/c5/ ... pinout.png Check this image and follow the traces for these signals marked FIXD0 to FIXD7, one of them will be disconnected.

[copados33]

Thanks Leonardo!!!, with that info I think I've found the problem, 2 severed traces: FIXD6 and FIXD7 from NEO-GRC, I followed both and they go underneahth the PCB to pins B6 and B7 from the cart SLOT.

Now, onto the most difficult part which will be to find a very thin wire to bridge these points... as I preffer to avoid, at any cost, to solder directly onto the SMD