Things You'll Need
Instructions
Grasp the battery with your needle-nose pliers. Push down with the pliers and turn left while ensuring the cartridge doesn't move.
Turn game over so the front is facing you and take off the top cover.
Locate the battery in the top right corner. Use the soldering iron to remove the solder holding the battery into place. Gently pull the battery toward you as you remove the solder. Use extreme caution to avoid damaging the game.
Place the replacement battery into place. Ensure the positive and negative sides are in the right places. Use your solder and soldering iron to secure the new battery.
Replace the top cover. Screw back together the cartridge.