My Powerbeats 3 won't turn on
The red light is on when I am charging but no matter how long I charge the beats they will not turn on.
This guide will enable you to be able to repair any issue with your PowerBeats3 Wireless Earphones
This is most probably a dead battery. At least it was the case in mine. I had tried resetting the headset, charging with different chargers, as soon as I unplugged it it turned off and never turned on. Also, when being plugged in, the led was blinking white and red 3 times.
It seems these earphones are not very resistant to water or even sweat. And when it enters inside, water shorts the battery, leaving it dead.
Good news is that it's possible to replace the battery, if you can buy one. The battery reference is AHB481221PR as described at Joe's. You can also find some on eBay, it seems the Bose bluetooth headsets are using the same battery. And Youtube will provide you with instructions on how to replace that battery.
And this iFixit guide repairing Powerbeats² is actually the same procedure.