If there is physical damage to the AC adapter or system, it will require replacement. Please contact Nintendo Consumer Support.
What to Do:
First, attempt to use a different electrical outlet, one that is known to work. Do not use any power boards, surge protectors, or extension cords. If this does not work, follow these steps:
Ensure that the Wii U console is not exposed to high temperatures and that it has proper ventilation (at least 10 cm away from obstructions).
Check to see if the AC adapter is a licensed accessory by verifying the model number (WUP-002(AUS)). If the AC adapter is unlicensed, and a licensed accessory is available, it may resolve the issue.
Check for physical damage to the AC adapter. If you find evidence of cracks, frayed cords, or other damage, it will require replacement.
If none of the troubleshooting above corrects your problem, perform the following:
Unplug all accessories from the Wii U console, including any external hard drives or other storage devices.
Unplug the AC adapter from the electrical outlet and from the back of the Wii U console.
Wait at least 90 seconds. This will cause the AC adapter to reset.
It is extremely important to wait the full 90 seconds. The AC adapter will not reset if you do not wait the full amount of time.
After 90 seconds has passed, plug the AC adapter into the Wii U console and electrical outlet. Do not use any power boards, surge protectors, or extension cords.
If your problem is still not resolved, please contact Nintendo Consumer Support.