I found that I can adjust the 5v in my Namco Exceleena cabinet PSU. I adjusted it down so it's showing 5v now. This cab has a Nanao MS9 chassis , all stock no mods etc etc.
Any ideas why I am only getting this when i plug the jamma expander into this cab? The setup is working, because when i plug it into my Atomiswave SD cab it all works fine. Just not on the Exceleena/Nanao MS9
Here's what the screen does
Here's what shows on the OLED, nothing else, it just shows this. Is it the 12v causing the issue? I read that this is what happens when the 5v is out, but will the 12v being this high trigger the system not to boot as well like the 5v does? I'm pretty sure the answer is going to be yes, i'll need to come up with a way to drop the 12v output because these PSU's definitely don't have anything to adjust 12v.