Many cartridges from the late 1980s to the early 2000s keep saves in memory that's powered by a small coin-cell battery inside the cart. After a couple of decades or more, that battery runs flat, and the game forgets your save as soon as it's switched off. Replacing the battery fixes it. If the save still loads, back it up first, because a battery swap can erase it. Our cartridge save battery replacements start at $15 per cartridge.
How battery saves work
Many older cartridges store your save in a small memory chip called SRAM. SRAM forgets everything when it loses power, so the cartridge has a coin-cell battery, usually a CR2025 or CR2032, that keeps it powered while the game is out of a running console.
The battery was never meant to be replaced, so it's usually held in by metal tabs soldered to the board. It drains slowly the whole time the cartridge isn't in use, and lifespans vary from cart to cart. Many original batteries are now running out.
Signs the battery is dying
- Your save disappears every time you turn the console off.
- The game says the save file is corrupted, or starts a new game with no option to continue.
- Saving appears to work, but the save is gone the next day.
- On Pokémon Ruby, Sapphire and Emerald, a message says the internal battery has run dry. Those games still save without it, but the clock and time-based events stop working.
Before blaming the battery, clean the cartridge contacts and try another console if you can. Dirty contacts can also cause failed saves and corrupted data.
Which games are affected
Any cartridge that saves to SRAM with a battery. Common examples:
- Game Boy and Game Boy Color: many RPGs and adventure games, including Pokémon Red, Blue, Yellow, Gold, Silver and Crystal, and The Legend of Zelda: Link's Awakening.
- NES: games with a save file rather than passwords, such as The Legend of Zelda and Final Fantasy.
- SNES: many games that save, including Super Mario World, The Legend of Zelda: A Link to the Past, Super Metroid, Chrono Trigger and EarthBound.
- N64: a small number, such as The Legend of Zelda: Ocarina of Time. Most N64 games save to chips that don't need a battery, or to a Controller Pak.
- Game Boy Advance: most games don't need a battery to save. The exceptions are a minority of games that use SRAM, plus Pokémon Ruby, Sapphire and Emerald, which use a battery for their clock.
- Sega: some Genesis, Master System and Game Gear games with save files, particularly RPGs.
Not sure about yours? A technician can open the cartridge and check in a couple of minutes.
Back up your save first
A battery swap can erase the save, because the memory can lose power for a moment while the old battery comes out. Some technicians keep the memory powered during the swap, which can preserve it, but that isn't guaranteed.
If your save still loads and it matters to you, back it up first:
- A USB cartridge reader that supports your cartridge type can copy the save file to a computer and write it back afterwards.
- For Pokémon games, trading your Pokémon to another game before the swap keeps your team, even if the save itself is lost.
If the battery is already dead, the save is usually gone already, and there's nothing left to back up. The new battery means your next save will stick.
How the replacement works
- The cartridge is opened. Nintendo cartridges use security screws that need a special bit.
- The old battery is desoldered from the board. Its tabs are welded to the battery, so it comes out as one piece.
- Any corrosion or residue on the board is cleaned.
- A new tabbed coin cell is soldered in, or a battery holder where there's room, so a future swap needs no soldering.
- The cartridge is closed and tested by saving, powering off and loading the save again.
Heat is bad for coin cells, so a new battery should never be soldered on its body. That's why tabbed batteries or holders are used.
Look after your cartridges
A fresh coin cell should keep a cartridge's save for many years, though how long depends on the cartridge's circuit and how it's stored. Keep cartridges somewhere cool and dry, out of direct sunlight, and play them now and then so you notice early if anything changes.
Get it done
If you have several games that won't save, they can all be done together. Choose Cartridge save battery on our booking page. See all retro console repairs.
Frequently asked questions
How long do cartridge save batteries last?
Often 20 years or more, but it varies a lot between cartridges and how they've been stored. Many original batteries from the 1990s are reaching the end now.
My game doesn't have a battery but won't save. What's wrong?
Many later cartridges save to chips that don't need a battery, like EEPROM or flash. If one of those won't save, dirty contacts, a faulty chip or a reproduction cartridge are more likely causes. A technician can check which it is.
Can I replace a save battery myself?
If you're comfortable soldering and have the right security bit, yes. Use a tabbed battery, never solder to the battery itself, and back up the save first.
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