Neo AES 3-6 video issues

Hey all,
I recently acquired AES unit (rev 3-6)
It has graphical issues that I'm finding hard(impossible) to diagnose.

1. Neogeo animated label doesn't display
2. sakura petals do not display prior or during story.
3. backgrounds/characters are duplicated up the screen with various artefacts.

Health bar/ timer and some other graphics display no problems.
Audio has no problems at all.

I've installed the diag bios but it reports no faults however i cannot test z80 since I dont have a cart to sacrifice.

Tested the data lines and cannot find any breaks.

The board is almost in mint condition just a pity about the fault.

Pics:
https://drive.google.com/open?id=11zlEGkXcY-ilEkXFtYe2fQb6XcVonHj1
https://drive.google.com/open?id=1bucoH-Ri99heIpPWkwSn97O9Ep51g4bo
https://drive.google.com/open?id=1w4ZlEkBMY_l6D9ff1K3ZkmNurmlvXMT4
https://drive.google.com/open?id=1yEmUz7I_EvGok9UUYYhH-CB7xSiU3l2i
https://drive.google.com/open?id=1pUlgXx7iyNMMzwLooSvozcM4627HgUXA
https://drive.google.com/open?id=1fjkxnonopyQUwDMERAzvl6R58k4G-UHP
https://drive.google.com/open?id=1R8hZNNzPa4mq8X12OCzhw1Rn9plDagl9

Video:
https://youtu.be/l9sxkMzEXYE

Awesome news!

I found the fault, its a broken trace between LO rom (pin 18) and LS244 opto (pin 15), remaking the connection with a jumper wire brings the graphics back 100%

YES!!!!!!

Bokoshi said:

Awesome news!

I found the fault, its a broken trace between LO rom (pin 18) and LS244 opto (pin 15), remaking the connection with a jumper wire brings the graphics back 100%

YES!!!!!!

Click to expand...

Glad you got it working! I’ve encountered several of these 3-6 boards with a tiny bits of corrosion in odd places on otherwise clean boards. MobiusStripTech even found one with a corroded trace UNDER the Neo B1 chip! It seems that these got tiny flecks of something corrosive on them in the factory and after many years they are starting to corrode through.