What cleaning/repair can be done to a Mega Drive cartridge slot?

Question

My Mega Drive's cartridges rarely boot. It's to the point where I sometimes don't want to change the current game because it'll mean 15 minutes of me constantly taking out and re-seating the next cartridge before I finally see a Sega logo.

Once in and seated 'correctly' however, the games play fine. No freeze-ups or weird graphical glitches. It's only the initial insertion where problems arise.

Likewise on my RetroN 5, the games are recognised straight away and are immediately dumped & ready to play. Thus I don't think the problem is with the carts themselves, but with my old Mega Drive's cartridge slot.

I've wiped down the contact points of the cartridges themselves, but is there any cleaning or repair work I can do to the console's cartridge slot itself? Are there any parts that are known to be prone to failure or can be repaired/maintained, or (in extreme cases) replaced entirely?

I'm using an unmodified 'Revision 1' Mega Drive (PAL) if it matters

Answer 1

Have you tried cleaning the pin connector inside the Mega Drive? It's fairly simple to remove the shell and access the pin connectors. (don't forget to remove the LED wires for model 1) I got a second hand genesis and used toothpicks to clean up the immense dust buildup in my console.

Early Mega Drives did not have BIOS - they boot directly from the cartridge. Later ones did had a small startup ROM that boots first known as the Trademark Security System (TMSS). This chip can stop roms from loading if it deems a game as unlicensed. You can tell if you have this TMSS if when you games boot, a short message "THIS GAME WAS MADE/LICENSED BY SEGA" or something similar.

I am not sure if this ROM is the problem since your sporadic loading is more indicative of more cartridge contact rather than a faulty TMSS ROM.