Sega Game Gear

Schematics

Problem DescriptionSymptomsSolutionSource
No power.Check out this comprehensive RetroSix article on the issue.Source
Won’t read game cartridges.- Check for bent pins in the cartridge reader.

- Check for degraded/cut traces

- Check for shorts around the MPU

- Check for shorts around the RAM
Pinouts for these chips
No audio.Most likely has a problem with the audio board. Capacitor leakage can often destroy traces requiring you to have to run a jumper wire to fix them. You can use an oscilloscope to help diagnose the problem

- Check connector to see if you have L and R audio and 5V. L and R should read around 100mV. If you don’t then you have a problem with the main board
- Use the schematics and an oscilloscope to diagnose any broken components or broken traces
- The trace that brings 5V to pin 2 on IC1 often breaks, you can run a jumper wire to fix it
Source