Chosen Solution
I have had this SNES controller for a long time that’s L-button is not working. So I took it apart today, cleaned all the parts and put it back together. But now the R-button doesn’t work either! So all the other buttons work great, except L and R buttons. I have no idea what the problem is. I used a multimeter to determine that current gets through the connection when button is being pressed. I see no visible damage to the circuit board or wiring inside the controller. Is there anything I can do to fix this?
I’m taking a wild stab at this one after looking at the internals of a SNES controller. It appears that the signal transfers through the circuitry after the button is pressed, very similar to how all of the buttons on that controller work. Open the controller again and take a look at the silicon pad that the L-button presses down on. If that pad is glossy or shiny then it’s not making a proper connection. There are at least two ways to clean up the silicon pad: Take an eraser and lightly rub the shininess away so you get a dull, matte finish. You can even take the eraser and clean up the contact on the board.Get a sheet of paper and gently drag the silicon pad across it until you get a solid, dark gray streek. Try those out and see if it brings the L-button back to life.
