So in a short time interval two of my SFC games got their saves wiped, seemingly as I booted the games up. I don't think it was the batteries in the carts going, because saving afterward worked. I think it might be the console I have. It has a thing already where I need to put a thick piece of paper in front of the cart of some games to have it "lean back" to make better contact in order to run.
But I have no idea how to fix a thing like that.
Or is it the old "hold reset when you power off" thing?
No, SFC has protection against such rogue writes, so there is no need to hold RESET when turning it off (despite what Act Raiser says when you save).
I believe it's most likely the battery running dry. When charge is low it will not be able to keep up a stable voltage at all times, which corrupts the SRAM. It may appear to work, but you never know when it will corrupt the next time, probably quite soon.
The connector problem might be fixable by cleaning the pins. Use cotton swabs or a toothbrush soaked in isopropyl alcohol (https://www.kjell.com/se/produkter/hem-kontor-fritid/kontor/kemi-spray-lim/spray-olja-isopropanol/luxorparts-ipaclean-isopropanol-250-ml-p18358) (95+% alcohol is fine). It may be easier to open the cartridge and scrub away on the pins and do the same in the cartridge slot of the SFC. If it has a battery, don't soak the whole board as isopropanol is water-based and thus conductive, so it may short-circuit something. Pour a little in a small bowl or plate and dip the toothbrush or cotton swabs in there and clean small parts of the board at a time. Don't use water or anything else as that would cause much more oxidation on metal parts.
Otherwise it might be the cartridge connector pins in the SFC that are bent so the connection isn't tight enough. If it wiggles a lot more than normal this might be the case.
I personally think the problem relies within your console rather than the carts themselves.
My US SNES also wipes save files out of nowhere, and it always happens when I have to pull a game out and boot it again because it wasn't making a solid connection (I now deliberately take my time before taking a game out and trying again so this isn't a problem anymore). The games don't read if you insert them the right way either, I always have to tilt them for them to work.
Unstable connections make file corruptions more likely, so what I think is happening is that your console corrupted the files the last time you played the games (or while you were trying to boot them).
If both carts inexplicably lost their saves at the same time then it might be the batteries dying, but assuming your SFC is as unreliable as my SNES I would personally try to fix the console instead. How to actually fix it is beyond my knowledge unfortunately.
I also think it is a problem at the console. :fire:
I guess even if the SFC is protected against rogue writes caused by powering it off, it's not protected against glitches happening due to unstable connection, which could still corrupt the SRAM.
Either way the 62-pin cartridge connector pins seems to be bent, so I would look in there and see if you can bend them back to get a tighter grip. In worst case you might have to replace the connector.