Today I recapped another Sega Genesis Model 2 VA1. Graphics, audio are fine. When I get to the select screen, the system with the controller plug in forces the down direction. I reflowed the connector and I still get the same problem. I even checked with a multimeter for any connections, and even looked. No solder bridges. Board is rather clean. It's not the controllers, since I cleaned them and they work.
you may have to remove the ports back in the 90s i had this probleam but never knew what a soldering iron was back then.