Chosen Solution

How do I fix error code 165-3000 on wii u gamepad?

Remove the back of the gamepad and the battery(will need special 3 pronged screw driver) and gently pop up the wireless module ( unless it is already dislodged due to dropping ipad) and reseat it. Replace the battery and the back of the gamepad and turn on.

To Fix This Problem Simply Hold down the POWER button on the GamePad to turn it off, and then turn it on again if the problem persists, then take the battery cover off and unlink the battery cover then link it but make sure before you do so that the POWER button is off of course then it should work lickity split if not the first try tho then the second or thrid then it should start to reboot like nothing happened.