Hello, guys.
As there was no videos about it I bought a pair of powerbeats 2 from ebay for 10 bucks and tried to fix it.
I will make also a video about how to get inside pictures from all electronics available in the us market (it what I used to figure out the best way to disassembly it).
This video will show how I did it and the best way to do it so you don't damage the bluetooth antenna or any other electronics inside.
The issue that I found is just that the 3.7V 90mAh battery wire breaks and as in any iphone, when you don't have the battery connected (or over a certain voltage) it doesn't do anything.
I know that making videos is not my strongest skill, but if it was useful to you, please, like my page.