I've been fixing SNES consoles for awhile now, but I've just now come across an issue I've never seen before. I've fixed up an NTSC SNES, but when I go to test it, I get a black screen. There's nothing wrong with the power, I get the red light, and I'm using the same AC adapter that I do for my personal SNES. There's also nothing wrong with the video cable or TV, because, again, I'm using the same connections as my normal SNES.
What is interesting, is when I switch the console on, my TV pops up the resolution of the SNES. It looks like something is going though, but it's not the picture or sound from the console. I've given the cart slot and the part on the motherboard that the cart slot slots into a good clean. I've tried changing mainboards and cart slots, same issue. Any ideas guys?