So Sevin got this Zelda cart and it wasn't saving for him. The reasonable assumption was made that the battery was probably dead. The first thing I did when it got here was open it up and check the battery. 3.2 volts still. I checked that the spot welds on the tabs were good since Sevin also sent me a Super Metroid cart for battery surgery which turned out it's welds were popped so the battery would lose connection when the cart was shaken.I popped in the Zelda cart and there was already a virgin 'Link' on there with no equipment or deaths. I ran around, collected a little money, then let myself die and saved. I shut down and unplugged the cart for an hour. Came back, file was still there ok.
I created a second save file. Played and beat the first dungeon and saved it with no deaths. Unplugged and checked after a while, everything was still there.Created a 3rd save file and beat the first dungeon with no sword since I'd never done that before. Unplugged, checked later, everything still there.Previous tests were yesterday. Went to check it again now and the first save is just gone. Second and third slot are fine and load up without problems. Maybe the first save slot is damaged on the chip? Anyone have any ideas?
I didn't find the right solution from the internet.