So as I sat there, trying to play through Contra, I noticed that the "B" button wasn't working too well. When I tried to shoot, the button was jamming and causing my gun to stop shooting. Gumming up the works in the most inconvenient timeframe, I ended up losing on the waterfall level. At that moment, I decided that I would indeed, show you how to clean an NES controller and unjam buttons that seem gunked up. it's quite fun and simplistic when you get down to the act itself. So lets dig in, shall we?
The first thing you need is an NES controller. This should be obvious. Otherwise, what would there be to complain about?
The next two supplies you need are ethyl alcohol and q-tips...possibly an X-acto knife as well. Make sure that you use the highest possible proof of alcohol. The lower the proof, the more time it will take to evaporate. Because I'm a friend of science, I have in my hands some 200 proof alcohol. The highest you'll probably be able to find will be in the 90's. That'll work too...just stay away from the 50-50 stuff. It'll stay wet for a bit longer.
The first thing to do is flip the nintendo controller over. There are six screws in the back. Take 'em all out.
Once you get the screws out, lift the controller back off of the controller. Flip it over and take all the screws out. Set the screws and the controller back to the side. You'll see the controller's PCB and the wiring's route. The wiring is wrapped around three lugs at the top of the remote. This keeps you from damaging the PCB when you yank on the controller and keeps everything snug in its place. Pop the wire out of these guides.
With the wire free, lift the PCB out of the controller. It should come out easily. I know that there are a few different models of NES controller though. Your mileage may vary. Take the PCB and the wire, setting them aside. We'll get to them in a minute.
Under the PCB, there's going to be some rubber pads (Or springs if you have the other NES controller variant). They're all held in place by little pegs and holes in the rubber. Just pull them out of the controller, setting those aside as well.
Now you're to the buttons. I will explain how these controllers work and hopefully this clarifies what we are about to do. When you push on the button, it exerts pressure on the little rubber pad. The pad has a conductive surface on the other side, which smacks into the circuit board, bridging a connection between two circuits. This will make Mario jump into a hole for the 28th time or pick the unsuccessful Tecmo Bowl dive play if you're me. When these pads get dirty, they sometimes can't bridge the connections on the PCB. Other times, gunk in the buttons makes them stick down when they're supposed to pop back up.
Take the buttons out of the controller top. Immediately you can see what's wrong with this controller. There's 25 years of garbage between the button and the controller top!
Take a q-tip, wet it in alcohol, and clean the controller top. Make sure to get every little crack and crevice. What's the point in doing a job if you're going to only partially do it?
Caution: Do not rub the controller so hard that the black surface of the contact area comes off. If you do this, the controller is practically useless. You must use some finesse when cleaning the pads and a light touch. Don't rub them repeatedly -- stop when lightly rubbing them with a q-tip produces no more. A magic NES genie will not come out and grant you three wishes.
This is also where the X-acto comes in handy. Occasionally the gunk in the controller is hardened and compressed over years of being jammed in the controller. Using the knife, scrape as much of it out of the corners as you can.
Once you get the top of the controller shell, do the buttons. The same logic applies here. Clean the D-Pad, A Button, and B-Button using the q-tips, alcohol, and X-acto.
Once you get the bottons and shell top cleaned, the real fun begins. Retrieve the rubber pads you removed earlier. Wet the Q-tip with alcohol, but press it into a paper towel to remove most of the wetness so it's just damp. Since alcohol can destroy rubber over repeated uses, you don't really want to soak the pads completely, and that's why we're taking the double precautious step of using pure ethyl alcohol and only slightly dampening the q-tip.
Clean the top of the pads first...
Then the bottom.
Once you clean the rubber pads, turn your attention to the PCB. Clean it pretty vigorously, using a liberal amount of alcohol. Make sure to get the black contact points very well. If they aren't clean, the button presses wont be registered well.
Now clean the shell. Make sure to get all of the loose dirt out of there. Clean the edges of the controller with the X-Acto knife and q-tips now since it is the easiest time to really get to them. After this step, you might want to take a break for a while. You're doing this to ensure that all the alcohol is evaporated and that all the components are completely dry.
Put the buttons back into the controller, making sure that the little guides on the buttons are in the correct positions so the buttons are freely sliding in the controller.
Put the rubber pads back on. Make sure they match up with the peg holes or else they could bind inside of the controller while you're in an intense Bases Loaded II match.
Put the PCB back into place. Make sure it fits down into place correctly and that the pegs which hold it in place are through their guides on the PCB. Once you're sure it's in the right place, wind the wire back through the wire guides as shown below. If you don't and you accidentally pull the cord sometime, you could yank the wires right off the PCB.
At last, take the top of the shell, put it on, and screw it down.
And there you have it! A good as new, freshly cleaned NES controller! It should work better than before and you can go try it out immediately!