Measuring Cartridge Battery

Many Game Boy® cartridges rely on batteries to keep save data alive. Here’s how to check if your battery is still good.

Which games have batteries?

• All GB/GBC games with save functionality
• Some early GBA games with real-time clocks
• SNES® games with save functionality
• Games with real-time clocks always have batteries

Later GBA games use EEPROM or Flash memory, which doesn’t require a battery.

What you’ll need

• Multimeter with DC voltage mode
• Screwdriver (3.8mm for GB/GBC, tri-wing for GBA)

Measuring steps

1. Open the cartridge using the appropriate screwdriver
2. Set your multimeter to DC Voltage (V) mode
3. Select the range: batteries are 3V, so use a setting just above that
4. Connect the probes:
   • Red (positive) to the + terminal (usually under the battery)
   • Black (negative) to the - terminal (usually on top)
5. Read the voltage

Interpreting results

Battery types

• GB/GBC games: CR2032 (larger coin cell)
• GBA games: CR1616 (smaller coin cell)
• SNES games: CR2032 (same as GB/GBC)

Don’t swap battery types. They won’t fit properly in the cartridge.

Replacing batteries

Battery replacement requires soldering skills or tabbed batteries. Before replacing:

1. Back up your save using your Operator device
2. Replace the battery quickly to minimize power loss
3. Restore your save after the new battery is installed

Many retro game shops also offer battery replacement services.

Tips

• A negative reading means your probes are reversed. Swap them
• Check batteries before buying used games if possible
• Original batteries from the 90s are well past their expected lifespan
• Even a “dead” battery may hold data briefly. Act fast!