Four Super Nintendos with Black Screen Problem - Trying to Fix

Hey there,



As you can see I have been attempting to repair four broken SNES consoles. The symptom is no picture or sound from three of them (Units #1-3). One of them (Unit #4) shares this problem, however, I noticed a couple of cartridges will show a display logo (for example, Konami logo appears) or I will hear the soundtrack playing with no picture (only happens with one cart - Psycho Radical Machine Racing).

I've troubleshooted the following:
- all sound modules seem to be working (tested them on a working SNES)
- all cartridge ports are clean and working fine (also tested them on a working SNES)

I've replaced all capacitors on Unit #4. The exact same symptoms appear after having done this. So maybe it is not a capacitor issue.

I am hoping someone here has some experience with fixing SNES consoles with the black screen display problem. I am pretty new to repairing consoles, though I've fixed (easy fixes) upwards of 30ish-40 consoles so far. Minor repairs, like the AC power plug port was broken (replaced the unit) or dirty consoles being cleaned up.

I am not familiar with going farther than replacing capacitors. This capacitor replacement was my first time soldering and desoldering... but I am eager to learn more. If anyone here has knowledge of where I can go for here, or advice on maybe swapping chips, testing if the connections are working, etc., I'd be happy to hear!

 

Have you got any working SNES consoles?

 

Yes, I do have one working one. I would rather not tamper with it though... as it is the SNES I use to play games with. I guess it could be useful for troubleshooting (I've tried the easy stuff with it, like checking if the sound modules work - they do, checking if the controller ports work - they do, and also the cartridge ports work on the working SNES). I am a bit afraid to do any soldering work to my working SNES just because my skills are amateur and don't know what I am doing at this point.

Hopefully there is a way to get these 4 SNES consoles working without having to tear apart my working, good SNES I use for playing games.

 

Im interested in your project. I have a SNES that displays, but has GFX issues.

* Star Fox no 3D GFX's show
* SMW random crashes and GFX issues.

 

So you haven't checked the fuses?

As per the other thread you bumped without reading the answers, it's usually the fuse, PPU or VRAM. You can replace the fuse, the others are probably not worth it and would be beyond your capabilities at the moment (SMD replacement).

 

Nah it couldn't be the fuse. The console (all the four consoles actually) power on just fine. If there was a problem with the fuse I'd assume the units wouldn't power on.

I've checked them all (it's been tough because I only have two ac inputs and four boards, so there's been some swapping of parts...)

Must be the ram or ppu I'm guessing... Which means that somehow these chips died. If that is the case, then why... Why did they die? Something must have caused it. What causes chips to just die? Will they all eventually go bad? It's kind of sad to think all SNES consoles will eventually meet their end.

 

Does all of your systems have 5v on the 7805.

 

Pikkon, I found the 7805 but am not sure how to check if it has 5v... guessing I need a volt checking device for that?

 

Wow, after a quick google search of "7805" and "black screen" and "SNES" I found a whack of information... seems like the 7805 is a big cause of this black screen problem. So I am gonna go out, buy a multimeter, and some 7805s and see if that solves the problem. Thanks Pikkon for mentioning that.. Will report back if it fixes the issue.
"

 

I repaired a snes mini that gave out 7v on the 7805,it would give me a black screen when trying to boot a game,replaced it and it works fine.

Thing is when a snes gives a black screen it could be a number of things.
Like this.
http://nintendoage.com/forum/messageview.cfm?catid=8&threadid=91278

Good thing your getting a mulitmeter,that can help out a ton.

 

I have a PAL snes with the same problem, powers on black screen. Only game I managed to boot was Mario Kart, freezes at Nintendo logo, please let me know if you repair yours
Thanks

 

So with a multimeter, I have read on one forum that I should use it when it is *not* powered on. Yet another person said I *should* have the SNES powered on. I have never used a multimeter before, so ... what do I do?

 

Power it on while you're measuring voltages. No power is for when you're looking for shorts.

 

I would highly advise getting a book on basic electronics before you do yourself or your consoles some damage. The "For Dummies" range are usually good at explaining things in plain English. Even a little knowledge goes a long way. You can even get specific books on using multimeters - I'm sure there was a good one in the Babani range.

You definitely need to practice soldering and desoldering before attempting to replace a voltage regulator.

If you're trying to find out what voltage a certain component is getting, how do you expect to do that with the power off? Of course you need the power on to see what voltage a component is getting! That's like saying you want to see if there are too many cars on a road - you'll close the road off then count how many cars are on it.

Seriously - if you're going to work on these yourself - get a book on electronics. Read it. Then get one on using multimeters (the electronics knowledge will be helpful to have first - don't cut corners). They're not going anywhere, they'll still be broken next week or the week after if you have to read the book first... only you're less likely to hurt yourself, the consoles or burn the house down!

 

I would like to bump this thread, i am in possession of 2 SNESs that are defective in this same way. one of them i bought at a flea market, the other is my friend's. they are both the same model as OP's, SHVC-CPU-01 with the separate sound module.

power supply is official Nintendo, pins are clean, fuses are fine, 7805's put out a solid 5v, caps look fine, reset buttons are fine, motherboards look immaculate, etc. they both will usually output a black screen with no audio, but some graphical randomness with a few random game cartridges (solid red screen, random colored pixels covering the screen (below), rolling horizontal lines)

everywhere i look for answers i see forums where people say they took theirs out of storage and it did this. everyone just says "just buy a new one" but with the rate that these things are failing i'm afraid a significant percentage of the SNESs out there are going to just up and die in the next few years, and i'm not satisfied with that prospect as the SNES is my favorite console.

if someone has a solution besides "buy a new one" please share.

 

Are you so sure the cart port is clean? I had an SNES with similar issues. Luckily it was a model 1 with a removable cart port. I removed the connector and boiled it similar to how you refurb an NES connector. Went from black screen and some logos to working perfectly first switch on every time.

 

i tried swapping the pins with my personal SNES which works flawlessly and it made no difference.

 

You can't say a capacitor is good just by visual inspection. Although I wouldn't expect that symptoms from caps, you say that lots of people's came out of storage to be suddenly broken, which points at component failure. The most likely components to fail in time are capacitors.

 

Cannot...un-see...vertical bar.

If it is a component that went bad, I would have to guess (and hope) that it was the vram. Is yours KM62256ALG-10? You could check continuity of your traces (despite them looking good) to the ram and even replace the ram to see if it makes a difference.

 

i considered buying a capacitor replacement kit but people with this problem have said it didn't help. i may yet at some point when i feel like spending the money, but i don't really expect it to work, i doubt bad capacitors would cause what happened in the picture i posted (i'm no engineer though)