Help repairing a Super NES

[Scrambled Eggs]

Hi, I have an old Super NES Model SNS-001 that doesn't seem to work. No matter what game I use, it always just gives me a black screen. I've cleaned the entire console inside and out, and still nothing. The only thing I can notice that is wrong with the insides is the EXT plug from the bottom of the console seems to have been removed. I love my Super Nintendo more than life itself, so somebody please help me!!! :sob:

[retroman]

did u try and replace the pins? (cart slot)

[jferio]

OK, is it connected with RF, or the A/V cable? Try a different one of either, or a different television if you can. Also, are you using the correct power supply with it? (10VDC, 850 mA)

You should also test another cart in it if possible, and clean the connectors on the carts thoroughly with 91% denatured alcohol.

[Scrambled Eggs]

I've already tried it on two other TVs, and I've also tried several games. I've tried both the A/V cables and the RF switch, and I'm using the proper AC adapter. I even checked the fuse, and yes, it works.

So you say it's probably the cart slot that needs a good cleaning? Thanks for the info, I'll tell you if it works or not :)

[Scrambled Eggs]

*sob* No, same exact thing.

[alec006]

Well,if your one of the lucky ones that have the SNES that has a removable connector,then just replace it with a new one.

http://www.nesrepairshop.com/online_shopping/index.php?productID=481&PHPSESSID=7445a

Of course,if you have a newer SNES and the connector is soldered down,there's always the option of getting a new motherboard.

http://www.nesrepairshop.com/online_shopping/index.php?productID=483&PHPSESSID=7445a

And you did say the EXT port was removed,someone correct me if I am wrong,but doesn't that disrupt internal circuitry being the port is connected directly to one of the processors?

Hope this helps.

[Scrambled Eggs]

thanks for the links but I don't think it's the connector at all. I systematically tested them one by one with a continuity tester and every one was connected at 0 resistance.

Is it possible that one of the chips might be burned out?

[alec006]

That could be a possibility,in fact my SNES doesn't play Super Mario Kart for some odd reason. I tested it on another SNES of mine and it works perfectly. Mine of course is one of the first 1991 models with the detachable sound processor or S-DSP chip by Sony.

You said you tested the resistance of the cart port,so that seems to be working perfectly,maybe one of the capacitors went out,that's always a possibility too. Again you said the extension port was removed,which that's really odd,due to the fact,its rarely used so why remove it? Notice in the picture that the right side of the cart port,the circuitry connects to the EXT port and the removable sound chip port.

Again,you could always buy another motherboard if you can't figure out the problem with this one,but granted,it has to be something simple,just finding it is the problem. Check for black spots around the chips connection to the motherboard,that could be a sign of a short or a burn out.

http://i103.photobucket.com/albums/m137/darkknux_2006/motherboard-huge.jpg

[Scrambled Eggs]

Thanks for all the info. I'll give that a check as soon as I have a day off from work (I work 14 hour days at a mill). All things considered, I don't think it could be anything to do with the EXT port. I bought the thing used years ago and never had the case open and it's always worked fine. It's only recently that it suddenly pooped out on me.

Again, thanks a lot for all the information :)

[Scrambled Eggs]

I'm going to test the chips before I replace any capacitors, but how do I go about testing them? I know that you touch a voltmeter across the pin 1 and the ground, but what value am I looking for?

[alec006]

What sucks is I can't seem to find Super Nintendo schematics anywhere on the internet. Anyone here have the motherboard schematics for the SNES? Otherwise I have no idea what the voltage would be for any of the chips.

[jb143]

5V, I can almost guarantee it. That won't tell you if the chip is working or not though, only that it's getting power. Also, Pin 1 isn't always Vcc. It usually is but not always. You should be able to put any of the chip part numbers in google and get a schematic for that particular chip though. Then you would know for sure.

[Scrambled Eggs]

5V, I can almost guarantee it. That won't tell you if the chip is working or not though, only that it's getting power. Also, Pin 1 isn't always Vcc. It usually is but not always. You should be able to put any of the chip part numbers in google and get a schematic for that particular chip though. Then you would know for sure.

Ohh. Thanks for the info. Is there a more accurate way to test the chips?