Neo Geo Memory Card Battery Replacement
The AES/MVS memory card uses a special CR2016 battery with tabs. The most challenging part of replacing the battery is removing the cover. These were applied using a 2-sided tape and removing them requires some heat and patience.
NOTE: If you want to keep your saves: Put your system into Memory Card test mode. For the AES, hold A+B+C+D on Controller 1 at power-up (with a game inserted). In this mode, you can copy the card's contents then remove the memory card to replace the battery, leaving your system on during the process.
- Apply heat to the back cover using a hairdryer or heat gun. You will want to get it fairly hot to help release the adhesive. You may want to hold the card with a glove. The card is fairly heat tolerant but don't go overboard!
- Using a sharp tool, such as an X-acto knife, lightly pry up on a corner of the metal cover. Insert the knife keeping it as parallel to the cover as possible. Slowly draw the knife around the edge to cut the adhesive free. If you apply too much effort or angle the blade too much, you may crease the cover.
- Remove the old adhesive. You don't necessarily have to completely remove it, just enough to get a clean surface around the perimeter of the card. For the most part it should peel off, but WD-40 or Goo Gone can assist in the process.
- Desolder the old battery, and solder in the new battery.
- With the battery replaced, apply a thin 2-sided tape to the cover. Don't use a foam-backed tape as it will add thickness to the cover and could catch the Memory Card slot.
- Remove the tape backing and reapply the cover.
- Return to your Neo Geo and copy the saves back to the card (if applicable).