Think my Japanese Super Famicom motherboard fried. Can that be fixed?

[greedostick]

Well, I feel kind of dumb....

I have been using my Japanese Super Famicom with the correct power supply for a few months now and after a storm last night I tried to power it up today and it does not work. After researching online I read you need a step down converter. I never had any issues with any of my other Japanese consoles in the past, Saturn, Famicom, Famicom Disk, PC Engine consoles... so I never knew this.

I have read about European people fixing their consoles by replacing a fuse. I have a Japanese console and would like to know if it is possible to get one of these fuses. I am pretty handy with a soldering iron so I think I can do this.

As far as checking the console what should I do? I have the lid off now and see a metal plate with a lot of large blue fuses under it, sticking out above the motherboard. I am guessisg that is where I need to be. How do I go through the process of elimination and find out which fuse or resistor is blown? Do I need a multimeter or do can I simply look at them and tell?

I heard a Genesis model 1 PSU will work on my Super Famicom, Tried it an no dice. I tried my Super Famicom PSU real fast in my Genny model one and it powers that up. So I must have something wrong on the board.

Finally, Wha is a good step down converter to get? Does Radio Shack sell them? There are a few in my neighborhood.

[Gameguy]

Before getting a step down converter you should get a surge protector, it sounds like a power surge caused the problems you're having.

[ApolloBoy]

Sounds like the fuse is blown, it's located next to the 7805 and is a 125V 1.5A Pico fuse.

[greedostick]

Awesome thanks guys. I use a surge protector but its useless because my house is so old I have no 3 prong outlets. So I have to use an adaptor.

[Pikkon]

http://www.mmmonkey.co.uk/console/ni.../snes-fuse.htm

[Niku-Sama]

Awesome thanks guys. I use a surge protector but its useless because my house is so old I have no 3 prong outlets. So I have to use an adaptor.

with the wall outlet adaptor your screwing the screw that holds the plate on through the metal tab that hangs down from the bottom of the adaptor right?

[APE992]

Lacking a voltage converter would've only killed the power brick which shouldn't affect the console. If the brick is dead then the console wouldn't turn on but if the power LED comes on then the brick is putting out some amount of current at a decent enough voltage to keep it happy. If you can check the voltage output to start with you can eliminate it as a problem.

And with the same tool if you can check to see if the fuse is even blown. Simply assuming it is the problem is a bad idea although my suspicions are with the fuse too.

[ApolloBoy]

Lacking a voltage converter would've only killed the power brick which shouldn't affect the console. If the brick is dead then the console wouldn't turn on but if the power LED comes on then the brick is putting out some amount of current at a decent enough voltage to keep it happy. If you can check the voltage output to start with you can eliminate it as a problem.

And with the same tool if you can check to see if the fuse is even blown. Simply assuming it is the problem is a bad idea although my suspicions are with the fuse too.

He said that he tried the Super Fami's power supply with his Genesis and it worked, so that's not an issue.

Greedostick, what you could do in the meantime is jump the fuse with a wire and see if your SFC still works. Don't leave the wire in there permanently as it's no substitute for a fuse and if something like this happens again with the jumper wire instead of a fuse, you could be looking at a blown 7805 or worse.

[APE992]

He said that he tried the Super Fami's power supply with his Genesis and it worked, so that's not an issue.

Greedostick, what you could do in the meantime is jump the fuse with a wire and see if your SFC still works. Don't leave the wire in there permanently as it's no substitute for a fuse and if something like this happens again with the jumper wire instead of a fuse, you could be looking at a blown 7805 or worse.

Bigger problem there is if whatever blew the fuse is still in place it will cause more issues.

[Gameguy]

Bigger problem there is if whatever blew the fuse is still in place it will cause more issues.

You mean if the storm he mentioned is somehow still there?

[MaxWar]

Greedostick, what you could do in the meantime is jump the fuse with a wire and see if your SFC still works.

Very bad advice, even for a 1 sec test.

You mean if the storm he mentioned is somehow still there?

It is not impossible that what blew the fuse might have damaged something else.

[greedostick]

I picked up a 4 pack of those pico fuses from the electronics store by my house yesterday. As soon as I get home tonight I'm going to install it and post back here. I am concerned though if this does work why it happened. The system was plugged in, bit not on when my house lights were flickering during the storm. Is there something I need to do to prevent this in the future? I read that powering on the system after unhooked discharges it. This is something I have always done but never knew I was suppose to.

[greedostick]

Is it possible the fuse just went bad? Or should I start tracing new issues if I do indeed get this thing to power up after installing the fuse? Sorry for the double post but I'm on my phone. The fuses I purchased on the package say...

PMF 1.5P
A-Fuse 1.5A PI
Dept: 54

The store I went in was awesome. It was some sort of GE electronics store that only sold fuses and other circuit board repair items. They even had arcade cab cap kits. I was surprised it was 5 minutes from me and I never knew. I was telling a guy at the game store my issue and he suggested it. Very good advice. Anyway, the guy said he was certain they would work. The 4 pack was 8.50 bucks.

[MaxWar]

There are good chances that this will work, btw did you actually test the other fuse with a multimeter?

[greedostick]

No, I was looking for my multimeter and realized I must have left it at my friends house when.we were working on his candy cab. I really hope it works. I really like my Super Famicom

[greedostick]

OK, good news. It worked! Took a total of about 10 minutes including heating up my iron. Much easier than installing a battery holder. So... now I am worried why this may have happened? Can these fuses just get old? or is there always a reason they blow? I'm pretty nervous about using the console now because i'm scared i'm really going to break something. Are there other steps I should take to check other parts of the board? I think I may take the whole thing apart and give it a good cleaning later this week.

As for the old fuse it did look a little off. I'm no expert on what fuses are suppose to look like. But I noticed there was some sort of lint on it. Looked kind of brown. Righ on the side of the black part of the fuse where it look like the 2 pieces are put together. Also, the sides of the fuse where the wire goes in looked really glossy, like possibly both sides melted a bit. Not sure if they just normally look like this, or if this is unusual.

As for the AC it is not a genuine Nintendo brand. It is actually this..

SFC AC ADAPTOR
INPUT : AC100V 20VA 50 / 60HZ
OUTPUT : DC9V1.2A

It's made by Game Joy Japan

Regarding the step down converter, I understand it prevents the power supply from blowing, but is it a good idea to get one of these living in the USA?

And as for general care of the console I read online you must discharge the console before unhooking it by powering it on. I'm a little confused by this because I thought you had to completely uinhook it then power it on since the light blinks when unplugged when powering on. I don't really understand how I could discharge it when it is still hooked up, unless it means to unplug it but leave the power cord still hooked in the console, then power on. I normally completely unhooked the console and always powered it on, not because I knew I was discharging it, but because I always thought it was weird SNES consoles did this. Could I have been damaging the console by unplugging the AC from the Super Famicom, then turning the power on?

Sorry for all the questions. I know it's a lot. But I think this will help plenty of people in the future who have similar issues. Seems like this info is kind of spread around the net.

[MaxWar]

First of all, do not worry.

If the console works now, then great, it was most likely just the fuse, no need to dig deeper unless you discover new issues.

About the whole "unhook it then power it on to make the light blink". This is to discharge the big capacitor inside the unit. You do not really need to do it unless you want to open the console for service.
This is a precaution to avoid accidental damage during repairs. I do not do this at all unless Im am working inside the console.

Here's what I think happened to your Console:
There was a surge, or several ones during the storm. Those surge made voltage spikes in the AC supply, which in turn made your SNES AC adapter output higher than usual voltage spikes.

Even though the console was not in operation during the storm, those spikes put a high voltage in the section of the console that is before the power switch. This section contains the fuse and various decoupling capacitors. It is very possible a momentary current there blew the fuse. But this should not have damaged anything else. The fuse did its job.

[Gameguy]

Regarding the step down converter, I understand it prevents the power supply from blowing, but is it a good idea to get one of these living in the USA?

The step down converter isn't just for stepping the voltage down, you can use it for stepping it up to 220V if you ever get European equipment. The better ones allow you to sellect the input voltage as well as the output voltage, they often can have several settings for output besides just 110 or 220 volts if you needed a more specific value(like exactly 110, or exactly 120 volts).


The best thing to prevent damage is to unplug your console or surge protector when not in use. Your house isn't grounded so that would be part of the problem, but your surge protector also sounds kind of cheap if it didn't protect anything. We've had surge protectors die while preventing damage to other equipment, that's what they're supposed to do rather than let a voltage spike through.

[wiggyx]

Zero need for a step-down. These adapters have an acceptable voltage input range and it's well above 120V. This is the oldest myth in the import gaming book.