NES Lockout Chip mod

My old front loading NES was no longer working. The old blinking screen would never go away. This can be caused by a few different ways. The most common is a dirty connection between the cartridge and the system. No amount of cleaning would fix this how ever, so a more drastic solution was needed, modding the NES’s lock out chip. There are many write ups on how the chip works, the short story is this was how Nintendo prevented unauthorized games on the system. The way to deactivate it is to disconnect pin 4 from the board and connect it to ground (or just cut the pin.)

First lets clean this bit of gunk:

Then we open up the case

Remove the metal shell


locate the lock out chip


now I will de-solder it with out braking the pin. (de-solder pin 4), the pin fell out after it was de-soldered


Works well.


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