Video: Sega CD Diagnostics

Originally Published on YouTube on 5/30/2020

I outline the process of troubleshooting a Sega CD, including continuity testing, voltage reading, logic probes, reading the schematics, and using a logic analyzer to see the assembly language executing on the CPU.

Thanks to Leo Oliveira for his help with deciphering 68000 assembly language and explaining the Sega CD bootup process.

Spoiler: the culprit ultimately ended up being the large Sega 315-5548 custom ASIC and the console wasn’t repairable.

Part 1
Part 2