32 replies to this topic

[thegamezmaster]

I still have my first SMS and years ago I accidentally grabbed the wrong power supply, plugged it in and turned it on. The light came on very briefly then went out. I know....idiot!  Anyway just found it, took it apart and saw no obvious blown components. This is the first deck I bought after the crash and would really like to fix. The SNES is just dead, got at garage sale, of course they said it worked NOT! My troubleshooting skills are bare minimum at best but I can measure things with a multimeter. Can anyone please help me in what things I should be checking on either of these decks? Any help someone can give me is greatly apopreciated, thanks.

[zylon]

Probably blew the regulator or a cap.   Hook up correct power cord and trace voltage until you lose it and go from there.

[thegamezmaster]

Thanks I'l try that. One problem is one has two components right off the power input but one seperate lines, they're grey and I have no idea what they are. Look like a resistor but solid grey in color.

[zylon]

Could be a diode.

[jamesk]

Edited below

Edited by jamesk, Tue Jul 12, 2011 6:31 PM.

[jamesk]

This might help if this is similar to you circuit. If not a picture might help. This was the only SMS schematic I saw.


To expand on Zylon with some pictures. Check for 5V coming out of the LM7805. If you don't see anything then you should suspect C50 or the LM7805. Applying reverse voltage to these components will cause them to die.

On the SNES I would start in the same place. Look for obvious signs of damage then check the LM7805 for 5v on the output.

Edited by jamesk, Tue Jul 12, 2011 6:35 PM.

[tz101]

SNES is most likely a simple 1.5 amp picofuse located toward the rear left of the console's main board. You can test this by taking the console case apart (special security bit required) and using a dual-alligator-clip wire to temporarily bypass this fuse. If the system powers on fine and plays games then a simple replacement of the fuse will do the trick.

Here is a link to a site that sells the exact fuse. I think you can get something similar at Radio Shack for cheap though.

Minimal soldering skill is all you will need and that SNES will be working like new again.

[thegamezmaster]

BIG thanks to all that contributed in helping me try to fix these. I'll check them out and see if this works. Again big thanks.

[thegamezmaster]

tz101, on Tue Jul 12, 2011 7:38 PM, said:

SNES is most likely a simple 1.5 amp picofuse located toward the rear left of the console's main board. You can test this by taking the console case apart (special security bit required) and using a dual-alligator-clip wire to temporarily bypass this fuse. If the system powers on fine and plays games then a simple replacement of the fuse will do the trick.

Here is a link to a site that sells the exact fuse. I think you can get something similar at Radio Shack for cheap though.

Minimal soldering skill is all you will need and that SNES will be working like new again.

What should the fuse read if bad?

[tpugmire]

Just bridge the gap using a paper clip or something and see if the light comes on.  If it does, replace the fuse.

[Cebus Capucinis]

If the SMS is fried and completely dead, I'll take it off your hands for projects (in this case, of course, meaning "buy it from you"). If you can't get it working, let me know!

[thegamezmaster]

tpugmire, on Wed Aug 24, 2011 2:42 PM, said:

Just bridge the gap using a paper clip or something and see if the light comes on.  If it does, replace the fuse.

Went to do that and the dumb thing started working before I could use the bridge. Just wanted to make sure it was dead and plugged in a ps and turned it on and the front light lite up. Go figure. Now to get the Sega Master System fixed. Thanks for the help everyone.

[Cebus Capucinis]

thegamezmaster, on Wed Aug 24, 2011 4:50 PM, said:

tpugmire, on Wed Aug 24, 2011 2:42 PM, said:

Just bridge the gap using a paper clip or something and see if the light comes on.  If it does, replace the fuse.

Went to do that and the dumb thing started working before I could use the bridge. Just wanted to make sure it was dead and plugged in a ps and turned it on and the front light lite up. Go figure. Now to get the Sega Master System fixed. Thanks for the help everyone.

Excellent! Always good to hear that a system is back up and running for some great game play!

[thegamezmaster]

Yeah glad the snes works. The sms I'm attached to as I bought it new when they first came out and would like to fix if possible. but I do appreciate all the help everyone has given.

[Majestic_Lizard]

I would have though the AC adapters would be interchangeable, other than the possible proprietary plug for the SNES.

I've used a Genesis power supply on a Turbo Grafx 16, Super Nintendo (had to adapt it), Nintendo, Duo, etc.

[Oge]

Quote

I've used a Genesis power supply on a Turbo Grafx 16, Super Nintendo (had to adapt it), Nintendo, Duo, etc.

You probably used a compatible PSU which had DC (which works for both Super Nintendo and Sega Genesis) instead of AC (which only works for Super Nintendo and NES). These things were oftenly sold on videogames stores and sometimes, being unregulated and not meeting the required consumption to stabilize the current enough, they were great... In reducing the lifespan of the console.

Cheers,
Oge

Edited by Oge, Sun Oct 16, 2011 1:47 PM.

[player 0ne]

any luck with the sms yet?  following voltage and reflowing solder joints is about as far as i car get sometimes, but it works..

[thegamezmaster]

Got the snes working but no luck with the sms.

[Atariman]

Did you successfully get 5V on the 7805 regulator? Years ago I did the same thing you did and had to replace the voltage regulator to get it working again.

[edweird13]

Did this to my Flashback 2 a year ago had to replace the regulator and the capacitor next to regulator. The regulator was burnt and the cap had exploded.

[thegamezmaster]

Thanks for the help. I'll check out the reg and will post results. Thanks again!

[thegamezmaster]

Measured the IC and VI measures about 15 volts DC and VO is zero volts. Does that mean the ic and C50 are bad? Thanks.

[FABombjoy]

thegamezmaster, on Wed Jan 11, 2012 2:28 AM, said:

Measured the IC and VI measures about 15 volts DC and VO is zero volts. Does that mean the ic and C50 are bad? Thanks.

Probably just the IC.  A very typical problem, SMS voltage regulators seem prone to failure.

[Atariman]

What power supply are you using? 15V sounds a bit high for a 9V supply even when it isn't loaded down. I agree that it sounds like the voltage regulator needs to be replaced. I don't know about the capacitor, though. I don't have a SMS handy where I am right now, so I can't look at the guts to know if the capacitor you are referencing is electrolytic or not. Can you post a picture of it?

[thegamezmaster]

I'll check it out and post later. Thanks for the help.