PCB Repair 101 – How To Clean and Reseat Roms

It’s a feeling that every arcade operator hates. You go to turn on your game and all of a sudden the screen boots up garbage or randomly starts resetting on you. Sometimes the game might play but there are glitches that distract from the arcade game. Every PCB board is a little bit different, so there’s no magic bullet on how to fix them, but one of the very first steps in PCB troubleshooting is to try and reseat the rams and hope you get lucky.

PCB repair can be intimidating, but this is actually a pretty easy fix to try. You’re going to need a wire brush, a flat head screwdriver and some electrical contact cleaner. You may also need your soldering iron and some solder if you aren’t careful.

contact cleaner

brush screwdriver

The goal of reseatting chips is to try and reenforce the contact that the metal makes to the socket. Over time corrosion and dirt can accumulate making it harder for the electrical current to pass through. The key to successfully reseatting a board is to go slowly and be careful. If you take a look at your board, you’ll see a number of chips that are nestled snuggly into sockets. Gently place one end or your flat head screwdriver underneath the chip and try and nudge it up off the board very gently.

pry chip

Once you’ve managed to pry the chip up a little bit, you want to stop or else you’ll bend the legs on the other side of the chip.

pried chip

Now that one end has been loosened, go to the other side of the chip and loosen the other end as well.

pried chip other end

At this point, you should be able to grab both ends of the chip between your fingers and lift it off cleaning without bending the legs on the chip. As you can tell from the photo, this particular guy is looking a bit grungy.

dirty chip

Spray a little bit of the contact cleaner on the legs and then use your metal brush to gently scrap away all of the dirt and rust. You want to be careful not to be too rough or one of the legs can fall off. If that happens, you’ll need to solder it back or a piece of metal. With any luck you should be able to clean it without a problem. If one of the legs do fall off, that very well could have been your issue to begin with. You can see how much cleaner our ram looks after it’s scrub down.

clean chip

Now that you have a cleaned chip, gently put it back into it’s socket. Make sure that all of the legs line up cleaning with the slots and then press it down firmly until it clicks back in. It’s really important that you put the chips back in the same direction that you took them out or else you’ll fry your board when you send power to places where it doesn’t belong. If you get confused, look for a notch at the top of the chip or writing. Generally, all of the chips on a board will be installed in the same direction.

Now that you’ve cleaned and reseatted your first RAM, you’ll need to go through and repeat the process on the rest. You may still need to make additional repairs, but in our experience this tends to solve the problem about one out of four tries. Best of luck with your arcade repairs. Let us know if you have questions in the comments or you can share your own tips and tricks there as well.

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