SNES won't save with good cart battery

jtvevox

I have a GPM-01 SNES that won't save games. The same Super Mario World cart saves on another SNES, but in mine it can read saves, but can't write new saves to the cart. 



I took the console apart and cleaned the 62 pin connector with CRC QD Eletronic Cleaner and a soft toothbrush and cleaned out any other dust and gunk. I examined the board for any burnt capacitors or diodes and everything looks ok.



The only lead I had was my EXT port was really corroded with green corrosion and a few rusty pins, and 2 of the pins were showing continuity when I tested them with my multimeter. I brushed out the EXT port with a wire brush, blew it out with air, brushed with CRC and the continuity went away. 



I'm still not getting saves though, any ideas or should I junk it?



Thanks!

Nes Freak

funny i have a snes game that would continue to work even without a battery. i left the battery out for a week and it still had its save and worked fine. maybe you have a bad trace or the save chip has gone bad.

jtvevox

The save chip on the cart? I know the cart is good because I tried it in another SNES and it writes and reads saves fine.

Nes Freak

Originally posted by: jtvevox



The save chip on the cart? I know the cart is good because I tried it in another SNES and it writes and reads saves fine.

oh so its the snes then?   thats weird.  maybe your pin is bad?  i know some of them are replaceable.  

jtvevox

Yeah it's something with the SNES itself. The 62 pin looks really good, no visible corrosion and I cleaned it really well.

Vanzant

Just to be clear...your Mario World cart won't save, but retains the saves from being played on another system. The console isn't deleting the saves just not overwriting? That's a new one to me. You can try a different power outlet, you could try another adapter and if that doesn't work you could try replacing the power cable on the motherboard.



Does this happen with other games that uses battery backed saves?

Nes Freak

Originally posted by: jtvevox



Yeah it's something with the SNES itself. The 62 pin looks really good, no visible corrosion and I cleaned it really well.

if i had your console i could test it with my snes controll deck tester to see whats going on

jtvevox

I did some more testing and here are my results.



I used my friends SNES that works and confirmed I could save and load games on Super Mario World, save and load drawings on Mario Paint, and create new save profiles on Zelda A Link To The Past and have them still be there after a reboot. So all three carts are good.



With my SNES I couldn't see any of the saved games on Super Mario World, but I could see them with my friends SNES.



With my SNES I couldn't load the drawing on Mario Paint that I had saved with my friends SNES, and when I saved a new drawing with my SNES I couldn't load it after a reboot, it just wouldn't let me click the load button as if there was no saved drawing.



Zelda actually worked fine. I was able to see the existing save profiles, create new profiles, and confirm save progress by collecting rupees.

Vanzant

So what we need to know is if the save on your friends machine...say you saved at the first yellow block level on SMW. It's gone when you try to play it on your machine? But is it still there when you try on your friends machine? Also, did you try the methods I posted above? I've never gotten a GPM-01 all of my GPM series are all 02's so I know nothing about them.



I'd honestly try to find somebody on here who ill trade you that thing for a working machine.

jtvevox

I'm not sure what you mean by power outlet, adapter, and power cable on the motherboard. I'm using the same wall outlet, power cable, and display cable for each console when I'm testing.



Correct, I did another test to make it a little more clear.



On my friend's console:

• Erase data on all 3 profiles
• Play to Yellow Switch then continue and save
• Power console off and on
• First profile shows as Mario A ... 2
• That profile loads with the Yellow Switch completed

Move same SMW cart to my console:

• It shows Mario A ... Empty
• Load A profile and Welcome! screen loads 
• Play to Yellow Switch and continue and save
• Power off and on
• Mario A still empty
• Load A profile and Welcome! screen loads

Move SMW cart back to friends console:

• The first profile shows Mario A ... 2
• That profile loads with Yellow Switch complete

My friend's console has no problem saving, reading, and loading saves, but mine can't even read that there's a save on the cart. My console isn't deleting saves when it tries to save or load though. I'm interested in what happens when the SNES tries to save or load to the cart, like what pins, chips, capacitors, or diodes or used, and can I test any of those to try and track down the short or bad component? My only suspicion is that the EXT port was pretty corroded, and I was getting continuity across 2 of the pins until I cleaned it out. Reading the pinouts here the EXT port does connect to the 62 pin connector so maybe there's an issue there? 



Thanks for helping me think through this one!

 

Ichinisan

Very strange. I suppose it's possible that some bad pin connections in the cartridge slot could affect reading or writing with a particular address range within the SRAM part of the memory map.

Vanzant

Thanks for clearing all that up and doing the additional tests! I Open and repair Super Nintendos almost on a daily basis and that's the first I have heard of this sort of thing happening. This makes me want to start doing more testing of my systems before I sell them...usually I just test games to make sure the range of games work.



At this point your options are very limited I'm afraid. You could gamble on trying a new 62 pin connector, but they cost 2/3 on just buying a working replacement console.