I have the same problem on my wii u! Have you tried to sync a wii remote or a pro controller? Mine can't at least. I suspect it is my bluetooth chip is faulty. Original wii at least even refused to boot if it there is a problem with bluetooth. I will try to switch the bluetooth board (as soon as it arrives) and will update this thread.
Wii u not opening any games, apps and even system settings (stuck at load screen on any case).
Fix: This may caused by a faulty bluetooth adapter (Test if you can sync a wii remote or pro controller to make sure). Change it and everything will work again.
