I was reading another thread where a guy was asking about this same thing so here it is. I Have a growing collection of snes' here that all have the same symptom. The power light lights up when i hit the switch and i get a quick flash on the screen but all i get is a black screen. No amount of cleaning will get these ones going again. Ive tried many things to get these working. Ive measured the voltage on the regulator and they all put out very close to 5v if not 5v. Ive tried cleaning the multi-out connections, looking for broken traces. nothing. Ive even replaced the caps on a few of them thinking that one may be internally shorted from leaking. ive also taken apart the reset switch on all of them to see if it was stuck. I have one board that is absolutely pristine but refuses to boot. anyone else have an snes like that? I dont think i have the equipment to properly troubleshoot these any further so until i come across an answer that works, the pile only gets higher.
Maybe it's lockout chip related. Can you tell if the CPU is held in reset? You may need a logic probe type of device or some way to tell if ROM is being read at all. Maybe on one of the boards you might try one of those lockout bypass mods and see if that gets games booting. Example: http://www.gamesx.com/importmod/sneslockout.htm http://kyorune.com/modding/article.php?id=4
Are you using an official power supply? What multi-out cable are you using? Are the cartridge's contacts clean?
i always use original power supplies. im running my snes' on a scart to component converter on a 60hz flat tube wega. the snes's that i have that actually work work fine on this setup. i think i tried cutting the lockout pin on one of the boards already and it didnt do anything.
