Instructions
Turn the Wii U off and unplug the AC adapter from the machine and the wall socket. Remove any controllers or other accessories from the Wii U as well.
Wait two minutes for the charge to dissipate in the Wii U and the AC adapter.
Plug the adapter back into the machine and the outlet and wait for the "Eject" button to turn white.
Press the "Eject" button to remove the disc.