Some footage of me playing around with Sega Mega Drive 2 serial 440005313 a while back. The DC input has already been repaired, but this particular console still has some rather spectacular video problems. Pac-Panic is doing things that I’m fairly certain it wasn’t designed to do!

At first, I suspected there might be a problem with the video circuitry or one of the connections around the AV socket. I gave the cartridge slot a clean, but that didn’t make much difference. There was still plenty of flickering, graphical corruption and the occasional error.

While examining the board, I noticed what looked like evidence of previous rework around the Sega 315-5660 chip. There was some residue around the pins, so perhaps somebody had been investigating this problem before me.

Then things got interesting. If I pressed down on the chip while the console was running, the picture appeared to become considerably more stable. As soon as I released the pressure, the problems returned. Now that’s a useful little clue!

It certainly suggests some sort of connection or board-related fault in that area, although it doesn’t prove the chip itself is defective. There could be a cracked solder joint, damaged PCB trace or something else responding to the pressure.

I also tried applying some heat to the board. Unfortunately, I may have been a little too enthusiastic, because the whole thing started flexing. Thankfully it returned to its original shape after cooling down, although the original fault was still there.

So where do we go from here? I’ve got some spare chips from another water-damaged Mega Drive 2, and I suppose we could start replacing components to see what happens. That sounds like another perfectly sensible afternoon of troubleshooting!

Stay tuned, because we’ve got more experiments coming up, including VRAM replacement and some other rather interesting attempts to bring this Mega Drive back to life.

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