Hello.
All of a sudden, my external HDD doesn't turn on when plugged in, no light or anything. I have all my data and things stored on it, and it doens't seem accessible. I've tryied plugging it into different sockets too.
It turns on with a green light, after 3 seconds it turns off.
I Just encountered this same issue...
Was plugged into surge protector, just not connected to computer.
Tried to plug into my mac today and does not want to spin up.... turns off after 3 seconds or so...
HD-HX2.0TU3
ser 15511401202679....
If it powers off after 3 seconds then it is not getting any power via USB, use a different USB cable and try on a different PC and see if it makes any difference.