This little device has been nothing but headaches since I bought it, but this is what I signed up for.

I originally found this GBM on eBay for around $100 USD which was cheaper than usual. The catch is that it was “Untested”. I figured I’d gamble on it, as untested doesn’t necessarily mean it’s not working. It didn’t come with a charger, so maybe it was just dead. Here are the photos from the listing:

Turns out, it was just dead. It came in the mail and powered on as soon as I gave it some juice. Nice! It didn’t read any games though. 

I took the device apart. Noticed I was missing some tri-wings underneath the battery which indicated I was not the first one to dismantle the device.. Once all visible screws are removed, the back half of the housing can be separated from the system. When removed, you’re greeted with a plastic frame. What I did next was remove the faceplate on the system by poking some tweezers into the two holes on the left side of the front housing. This should unhinge the left side of the faceplate, and then it swings off. Place the device face-down.

Once the back housing and faceplate are removed, you can lift the innards of the GBM out of the front housing. Start with the top and tilt the charge port up and away from the housing. As you pull, the main PCB will come out of the front housing. Be careful of the start/select buttons at the bottom as they may get caught on the housing while you’re trying to do this step.

Now that both sides of the housing are off, you can start tearing down the insides. There are three JIS (similar to Phillips) screws securing the plastic frame: one on the top left, and two on the right underneath where the battery tray would be. Remove these three screws and you can remove the plastic frame. Be mindful of the clip near the Left shoulder; you may just have to jiggle the frame a bit to get it off. When you remove this frame, the shoulder buttons and volume rocker may spring out. Keep an eye on those.

You can now remove the metal cartridge shield by unscrewing the one screw on its top left. After this, you can remove the screws on the right that secure the PCB to the plastic frame beneath it.

You should be able to separate the PCB from its plastic frame. Keep in mind, the screen fits perfectly in the frame, so you will have to twist the screen diagonally to allow it to fit through the frame. (It will be easier to disconnect/reconnect the screen while the PCB is off of this frame, so I would advise against removing the screen before the plastic frame.)

The screen is connected via two ribbon connectors: one fat cable for data and power, and one skinny cable for the backlight. Be careful when removing/installing the thin cable, as that latch system is prone to breaking. Mine did, and now I have to use Kapton tape to secure that cable. It’s super fun.

I cleaned each piece with isopropyl alcohol and soap and water where applicable. Upon reassembly, the system read games. Nice! Sweet deal for $100, right? Wrong.

Shoulder Button Replacement

A few days later I realized the shoulder buttons didn’t work. I’d already cleaned them when the device was apart, so I had to replace them. Luckily, these shoulder buttons are similar to those on the DS Lite and those switches were easily purchasable on eBay for a few dollars. 

I’ve never desoldered anything before this, so I had no practical idea of what I was doing. I figured I could just gently heat the solder holding the component on and remove it. Some internet searching confirmed this would probably work. There are better ways to desolder things (like using solder wick or a desoldering tool,), but this might be fine. Worth a shot.

There are five contact points per shoulder switch. Three contacts on the bottom & rear of the switch and two prongs on the sides that sit in holes on the PCB to ensure they’re in the proper place. All of these points are soldered onto the PCB.

Being new to soldering and especially de-soldering, I kept the soldering iron temperature low and started trying to remove the left switch. I believe I started at 365 Celsius, and gradually increased the temperature if I wasn’t able to properly heat the solder. A little bit of foreshadowing: I was not really able to properly heat the solder at all. 🙂

Starting at 365 got me no results. I was having trouble already due to the location of the switch on the PCB. When working on the left shoulder switch, there is a capacitor located directly below the bottom of the switch, which your soldering iron tip will make contact with if you’re not careful. I switched to a fine tip for this, but the fine tip made it even trickier. The fine tip of my soldering iron is very pointy and I must be very precise in order to get anything accomplished with it.

I increased around 10 degrees Celsius in between attempts, ending around 415 when I started to worry about using such a high heat in this application. I have no experience soldering before working on Game Boys, but 415 degrees seems really high. When I was adding wires and installing IPS displays on consoles, my solder was working perfectly in the 360-380 range. 

After around 2 hours of poking and pulling, the bottom of the switch started to loosen. The technique here was to heat the three contacts underneath the switch first. Once these came free, I would try to slightly bend the switch up and away from the PCB from its bottom. Then, I could desolder the two side prongs and completely remove the switch. With enough patience, this worked. 

Same process for the right shoulder, however this one’s location has its own quirks. Instead of having a capacitor in the way, this shoulder button is placed on a small peninsula-like piece of the PCB that isn’t much longer or wider than the switch itself. Imagine the GBM PCB is Oklahoma, and the right shoulder switch is on the panhandle and the panhandle is only as large as the switch. 

This being the case, the nature of this removal becomes treacherous. Removing the switch involves heating and light prying, but the prying on the switch also risks bending/twisting the PCB. I had more confidence with this switch after being successful in removing the other side, but the new issues on this side were far scarier for me. With the same patience as the other, I managed to get the switch loose from underneath and once I sufficiently heated the side prongs, the switch was free.

Ya know what else was free? One of the three solder pads from underneath the switch. It came off with the switch. This is when I began shouting expletives. 

How to fix this? No idea. To me, this was project-ending damage. I had no clue how to fix it. The solder pad is a thin rectangle and the one I lost was on the right side of the three total pads. The pad broke off exactly where the switch contacted it and the damage did not extend any further along the trace. I decided to gamble: I’d install the switch as if I didn’t lose this pad and I’d hope that either this pad was not actually necessary, or that the contact on the switch would just barely make contact with the edge of the copper trace where the pad broke off.

Somehow, it worked. A true Christmas miracle. The install was not particularly pretty, as placing the switch in its place and trying to guide it onto its pads and support holes while heating the solder was tricky. Patience is the theme with the GBM and this part is no different. Once installed and secured, I reassembled the device just enough to power it on and boot into a ROM that I use to test the buttons. Both new shoulder buttons were working. Wow. 

I finished reassembling and encountered a new issue: my average-at-best install job of these shoulder switches left the switches sitting slightly higher on the PCB than the old ones. Because of this, there was no room for the plastic shoulder buttons to rest on top of the switches. The left switch had just enough clearance to make it a crisp, perfect button press. Not messing with that one. However, the right switch, the one with the missing pad, was passively depressing the switch due to the lack of space between plastic button and switch. 

There’s no way in hell I’m removing that switch and trying to reinstall it. No way I’d get lucky enough twice and I really don’t want to test that luck. I decided instead to take my nail file and file away at the underside of the plastic shoulder button. Being that one shoulder button fit perfectly, I figured I could shave off a fraction of material and solve my problem. I was right! Filed some plastic away from the button’s underside where it presses the switch and it was the perfect solution. Cool beans.

Start/Select Button Repair

I once again reassembled the console and before placing everything into the metal housing pieces, I went back for one more test. All was looking well until I noticed the start/select buttons weren’t working. I had not done any work near those buttons and they were working before, so what’s the issue?

Turns out my luck ran out. The switches failed at a horribly coincidental time. It was like some sick twisted joke. I had spent agonizing hours trying to fix these shoulder buttons and now the start/select buttons fail? UGH. This sucked, however I had a better feeling about this repair than the shoulders. I found one YouTube video detailing how to replace these buttons. There are nearly-identical replacements on Mouser and the solder pads are exposed. Four per switch, on the corners. Simple fix.

It was not simple.

Similar to the shoulder buttons, removing these switches took an eternity. For some reason, perhaps user error, I could not desolder these components. They just wouldn’t come off, no matter how hard (yet carefully) I tried. Eventually they did, however, not without irreversible damage yet again. I lost one pad on the bottom right of the start button. Yay!!!! Super fun!!!!!

In addition to the lost solder pad, the legs on the switch were extremely difficult to desolder and in a few cases, stayed on the board despite the rest of the button coming off. Out of the eight total solder pads, two of them refused to desolder and the button leg just broke off when removing. Again, this could have been user error on my part, but with how difficult the desoldering process was for this device’s components in general compared to the people who’ve posted on YouTube, it seems like this device may just be difficult. Maybe that solid purple water damage sticker has something to do with it.

Anywho, I figured it wasn’t a big deal if the contact legs from the buttons were still on the PCB. As long as I could still solder to it, I’d be fine. Turns out, this was true. I installed the select button and it works just fine with being soldered onto a broken leg from the old switch. The start button, however, the one with the missing pad, did not work when installed as-is. The luck I experienced with the shoulder button did not carry over to the start button. This missing pad was important and I would need to fix it, no way of getting around it. I removed the new start button. When I did this, I noticed another issue: a second pad had come off. Now the bottom two pads from this button were gone. It must have been dislodged during the removal of the original button but did not break completely loose until now. The real fun began here.

This would be a great spot for a commercial break. If you’re reading this, consider taking a short break and drinking water. Maybe do a lap around your room or living space. Check in with yourself. Okay, back to the action.

According to the internet abroad, repairing a PCB like this requires one to scrape away the solder mask on the PCB to reveal the copper trace beneath it. Once you have exposed an area of copper, you can solder a “jumper wire” to that spot and lead that wire to where you’ll be connecting your component. In my particular case, the start/select buttons are on a separate piece of PCB from the main board that is connected by a ribbon cable sandwiched into the main PCB (instead of being attached via a latch or connector). Because it’s sandwiched into the main PCB, you can’t disconnect this piece. This makes working on the start/select buttons very difficult. Most of this repair was done with the PCB taped to my desk to hold it in place.

Step one, scraping away the solder mask, was terrifying. I’ve never done this before and this PCB is so damn small that scraping too hard or in the wrong spot might cause permanent damage and cause me to scrap this entire project. This piece of PCB is tiny and the copper traces are even smaller. A microscope would be amazingly helpful for a situation like this. With a fresh exacto knife, I gently scraped along the trace right next to where the pads came off. I think I would have been better off to expose the copper trace in locations further away from the missing pads, but I wasn’t confident in which traces led to these pads due to the small size. My best bet to avoid messing up was to scrape away where I knew that there would be copper going to these two pads. 

With a combination of an exacto knife and a fiberglass pen, I got a small sliver of copper exposed right next to where both pads were pulled off. I needed some really thin wire to solder from here to where the pad would be and the only wire I had was braided. With the miniscule length I need, braided wire won’t work. I don’t even have enough space for a wire thicker than around 28 AWG. The copper traces for the button run underneath where the button sits, so any thicker would impede on the space the buttons need to make contact with the PCB and also sit within its plastic frame of the console.

I went over to the store and picked up some bare copper 28 AWG wire. I figured this would be the answer to my problems. However, upon attempting to solder this wire to the small copper exposure, I failed. This could be user error, but it could also be that I didn’t expose enough copper to properly make a connection. Maneuvering this fractional piece of copper wire around the tiny PCB was surprisingly easy, so it’s unfortunate that this fix didn’t work for me. Luckily, I learned about one more method I could try. Copper tape.

Copper tape is exactly what it sounds like: thin copper strips with adhesive on one side. Some copper tape is conductive on both sides, which is what I need here. I thought if I could place down two tiny pieces of copper tape to connect the exposed copper to where the pads used to be, I’m golden. It almost sounded too good to be true. I found some copper tape on Amazon that claims to be conductive on both sides and most customer reviews confirm this. Low and behold, however, it was too good to be true after all.

Ribbon Cable Troubles

The copper tape didn’t work, exposing more of the copper trace wasn’t working, and I couldn’t think of any other issues. Until I looked at the ribbon cable and noticed it might have been damaged. The ribbon cable had a hard crease right where it folds over itself. Perhaps this was the problem all along.

Morale was at an all-time low. Did I spend all this time trying to replace buttons, damaging the PCB for nothing? Was it the ribbon cable this entire time? Yea probably. Can’t change the past though, so we march on. Luckily, I’m not the first person to damage this ribbon cable and there is documentation online on how to use wires to replace the ribbon cable. See here.

There are five wires you need to add. One for each of the following functions: Start, Select, Ground, Red LED, and Blue LED. There are small vias located on the underside of the daughter PCB that you can solder wires too, with the exception of a ground. You’ll need to scrape away the solder mask somewhere and solder a wire to the exposed copper. On the main board, there are five pads/vias that you can solder all the wires too. They’re all located next to each other on the lower left side of the board.

My lack of proper equipment was the star of the show for this section. Up until now, I had nothing to hold the GBM board while I was working on it, so it was sliding all over my desk while I was trying to solder these tiny wires to the microscopic vias without a magnifying glass or microscope. It was torture. Luckily my brother noticed my struggles and lent me a PCB holder that worked very well to keep things sturdy while I worked.

My other issue is that the wire I was using was braided, not solid core. This meant the tiny wire ends were fraying all over the place while I was trying to solder. I eventually got them all soldered to the daughter board, but it was not fun at all.

Soldering the other ends of the wires to the main PCB was arguably worse, as the contacts are all so close to one another that tinning the contacts was almost impossible without bridging them together under a small blob of tin. As before, I got through it after some time. All five wires soldered on both sides.

I reassembled and was half successful. The start button was working, but the select button was not. Could this be because of the damaged pads under the select button itself? Was it because of the wire I soldered? No way to know for sure. I tore the console apart again and the select wire fell off. Apparently I didn’t go a good enough job soldering it. Despite my best efforts, I just couldn’t get the wire soldered well enough on either end. I gave up and ripped it out.

Aside from the select button not working, the console is functioning normally and I’m fine with how it is now. The select button isn’t important in any of the games I like to play anyway, so it’s fine by me. The only thing left for me to do is to paint the OEM shell I have so I don’t have to keep using the aftermarket one.

Painting the Shell

I really wanted the Pokemon Center Game Boy Micro, but they’re too expensive for me. Unfortunately, I’m not able to get a shell to match it either. The next best idea for me is to paint my shell red and use the black faceplate I have to get a similar look. However, I had a neat idea and decided instead to paint the shell blue with some Subaru World Rally Blue paint that I had left over from my car.

I painted the shell once and it looked pretty bad, so I’m currently redoing it. I will make sure to update this post with new pictures once the new paint job is done.