Really weird SNES issue..

[Wolfshadow]

So I bought a SNES recently I knew was having a problem displaying games, but no real specifics of what the issue was.

So we tested this thing out, and I can't seem to find any info on what the problem is.

So, it boots up, right? And you think it's working... We tested it with two games- Chrono Trigger and Mega Man X. We also have my childhood SNES that works perfectly so we could test that and just ensure that it's the new SNES we just got, not the carts etc.

So with Chrono Trigger, the whole first screen loads.The title screen, etc. If it goes to fade to run through the demo sequence, the game stops, but still plays audio. Just nothing else, visually. Black screen.

With Mega Man X, we get the whole "COPYWRITE CAPCOM" yadda yadda and when it goes to fade out and start the game, again, goes to black, doesn't go any further than that.

I can't seem to find any info on what, exactly, the issue is, how to fix it, if it IS fixable, etc. I'm just getting started into console repair but this is my first SNES. Any tips would be grand.

Thanks! :3

[Niku-Sama]

do you lose control too?

like for instance in megaman x if you hit start a few times can you hear the game start the intro level on the bridge?

[Wolfshadow]

No, not really... it just never goes past the CAPCOM screen upon boot.. I figure it's the PPU..... And I'm not experianced enough with soldering yet to want to try repairing that...

[Niku-Sama]

so while you were away I got a SNES with a similar problem, it was in pretty bad shape on the outside but the innards seemd ok, no corrosion or damage of any sort to the PCB.
some logos, megaman X did the Capcom logo and then nothing, other games did similar if they had a logo of that sort. gradius III had a bar pattern but it usually does when it boots any way.

I searched and searched, if it were the PPU I would imagine the problem would be consistent, any thing graphical wouldn't work or would all be garbled but at least go into the game.

after some searching I found some one with a similar problem as ours and said the 7805 wasn't quite putting out enough for the board. so I tried replacing the one on mine and it flickered on and immediately right back off like it had blown the fuse except theres still continuity across the fuse, its still good. I jumped it to be sure and still no life.
so it seems to me that mine was a combination, the 7805 was putting out barely enough voltage but I didn't test for amps. I have a feeling that my known good 7805 was more than some of the components, most likely caps, could handle any more due to age and that's why it seems like the fuse has popped.

shortly after that I had a similar thing happen with a master system. replaced a VRM and it popped a cap, replaced the cap and the system booted. come to find out though that master system has more problems still but that's for another thread

[Wolfshadow]

so while you were away I got a SNES with a similar problem, it was in pretty bad shape on the outside but the innards seemd ok, no corrosion or damage of any sort to the PCB.
some logos, megaman X did the Capcom logo and then nothing, other games did similar if they had a logo of that sort. gradius III had a bar pattern but it usually does when it boots any way.

I searched and searched, if it were the PPU I would imagine the problem would be consistent, any thing graphical wouldn't work or would all be garbled but at least go into the game.

after some searching I found some one with a similar problem as ours and said the 7805 wasn't quite putting out enough for the board. so I tried replacing the one on mine and it flickered on and immediately right back off like it had blown the fuse except theres still continuity across the fuse, its still good. I jumped it to be sure and still no life.
so it seems to me that mine was a combination, the 7805 was putting out barely enough voltage but I didn't test for amps. I have a feeling that my known good 7805 was more than some of the components, most likely caps, could handle any more due to age and that's why it seems like the fuse has popped.

shortly after that I had a similar thing happen with a master system. replaced a VRM and it popped a cap, replaced the cap and the system booted. come to find out though that master system has more problems still but that's for another thread

I'm completely new the capacitors etc, the most soldering I've done is soldering DS Lite speakers to a new top screen's ribbon cable. (I'm a girl, so while I enjoyed trying to understand my father's tinkerings in such things, he never was a mechanic/etc or could really figure out this stuff, I always wanted, but obviously girls don't get taught how to solder electronics!!! I know it's a long road ahead before I can figure this stuff out for myself.. Thank god for YouTube!)

Anyhow, what part is the 7805? I assume that's a fuse.. I bought a SNES motherboard to possibly replace this one or use for parts to repair the old one, but it doesn't have a power plug- someone went and removed it. I can't turn it on obviously to figure out what may be wrong.. Does anyone have schematics for an SNES or pictures of the more major components, what I should be looking for, etc?

[Niku-Sama]

7805 is the voltage regulator, its screwed to the metal plate that arcs over the back end of the board.
you should be able to test the voltage with it in place using a multi meter

and gender has nothing to do with it. I work with a gal that has done electronics repair for 30 years before she wound up in the same department as me.
she still replaces phone screens and tinkers with all sorts of things in her spare time