Nintendo NES Controller Button Repair

Nintendo NES controller button repair

There may be different PCBs made for NES controllers over the years
The controllers I have seen look like the photos here. The circuit board button contacts are copper trace with green conformal coating and then black carbon on top. The carbon wears off after years of use. Copper is a good conductor but it oxidizes quickly so it will always be coated with some protective layer. The carbon pads are common conductive coatings used in button design. You can scrape off the carbon, exposing clean copper but this doesn't usually last very long before needing cleaning. 

To solve this I have made some nickel fabric conductive tape used for EMF shielding. The adhesive is conductive so placing it over the remnants of carbon will conduct over the entire adhesive piece. When placing the nickel patch just make sure the two halves cannot touch each other. The fabric can fray a little at the edges and even a tiny string jumping the gap could cause the switch to short and always be activated. 

I have not tested this with rubber buttons but it should work. I have only tested it using ButtonWorx™ repair pad over the nickel repair pads.  

Note: you DO NOT need to (and should not) remove any remaining black conductive coating before applying the nickel tape patch.