If you turn the charging station upside-down, on the bottom plastic you will see two edges which connect to the inside side and top plastic which is one moulding. Pry the bottom plastic off (it's just clipped) and then undo the screws and the white side plastic comes off.
Any chance for a photo of the MB? If the pads are still in their place, you can use a soldering iron to reattach the broken part. If pads are torn off, you would need to use a soldering iron with some thin wire to connect existing lines with pads.
It may be caused by a faulty battery. If someone from your family or friends have the same model, you can try using their battery and check if it works. Or you can buy a new replacement battery. It’s up to you which option will you choose. Try that and if won’t work, let us know so we can troubleshoot it further.
If we are talking about New 3DS XL, the Micro SD card reader is a standalone module that can be bought separately from Aliexpress for about 9-10USD + shipping costs. Replacing it takes about 10 minutes. Look it up in guide for this model.
Hi @sonicboi , You can check the pins in the port with a multimeter for continuity. Maybe the data lines got damaged. Other way is to hack your console and use VitaShell which is a file manager that allows you to transfer data via FTP protocol. But this is rather a workaround than a fix.
Hi @darkmagenta, You can try to fix those but that requires some soldering skills and equipment. You can try to get a replacement board but it will be more expensive, especially that both of the tapes look damaged so you will need to replace those components as well.
Hi @istvan_kreisch , Please check the daughterboard that has the battery terminal on it. I had to replace at least two of them. If you have a second working console, you can try swapping the daughterboard and see if that resolves the issue.
I don’t think that making holes in the case will give you any more advantages than other things that you described. After dusting the inside off and replacing the thermal paste (Arctic Silver 5 is one of the best options), keeping it in a well-ventilated place and allowing fresh air to pass trough should do the work. The stock fan is enough as long as it’s fully working and does not have broken wings. As you know, reflowing the chip may not be enough as the solder balls used by the manufacturer are lead-free, and those have tendency to crack. Even reballing is prone to failure as the chip is affected by high temperature.