Probably Dead From Water?

Skye Tor probably not but you can always try. For now you want to stop using it, charging it or trying anything else.

Disassemble your 3DSXL using these guides . You must remove all EMI shields from your motherboard. If you do not remove those, you might as well not do anything. After you removed those, clean the whole board, connectors and all with +90% isopropyl alcohol. Follow this guide , and even so it was written for a Apple iPhone all the points are still pertinent to your device. While you clean your board, check for any obvious damage, like burned or missing components etc. When it is properly cleaned, you must replace the battery. All these steps are to avoid delayed failure caused by corrosion. Best thing to do would be to clean it with an ultrasonic cleaner, but if you do not have access to one, this will at least help. Once all this is done, reassemble your game and reevaluate. Until it is cleaned, everything will only be a guess. It is possible that you have a least a bad LCD and replacing the display assemblies may fix it. Even with all this, water damage has only a small chance to be fully repaired, but at least you can give it a try.

If unsure of anything, you can always post some images of what you encounter with your QUESTION. That way we can see what you see. iFixitでの質問に画像を追加する方法