Chosen Solution
This was a working SP. I wanted to install a USB-C mod for a more modern charger. After installing it, the screen displays only lines. The sounds and buttons work normally, so the game is running but now video. I removed the mod and it worked again. I did this twice before I realized that it would not work with the new hardware installed, but worked fine without it. I eventually removed the usb-c for good and thought it might be a good idea to change the cap for good measure. It is now doing the same thing it did with the usb-c mod. I have obviously have a failing component that is getting stressed by these additions, but I cant figure out what. I have another SP and checked the screen to make sure it was not that. It displays the same lines with the second screen. The usb-c mod is off at the moment, but I cant put the old cap back on since you practically have to destroy them to remove them. I’m at a loss. Can someone give me some ideas as to where I might start looking? Thanks Here is the result.
Ok, so I managed to correct this problem. I had to reflow the CPU and everything began working normally. I’m guessing there was some micro fault or bridge in one of the video pins. I spread flux around the CPU and then used my hot air at 380c to heat around the chip until pins were shiny. I was careful not to put too much heat into the board for fear it could have damaged the buttons on the back. Thankfully this worked for me.
Here are some pictures I took during the evolution of this project. After USB-C mod second installation
Here is the Capacitor I replaced.
CPU Before pin reflow.
And after pin reflow
Which leads to a happy Gameboy.
