Crashed phone vibrates when plugged but doesn't turn on
This is a weird story, it's even hard to explain so i will make a punctuated list with everything that happened, trying to be as much clear as i can:
1 - the phone crashed, screen broken, black and touch digitizer not working;
2 - the phone kept to stay powered on, so i was able to plug it to the pc and save all of my data;
3 - i opened it and magically the screen started to show something, like the 10 % of the screen was now working (the bottom part, near the unlocking shape), and that gave me the chance to check the sensors which were working, so that gave me the feeling that the phone wasn't broken completely, and just a screen replacement would have helped me fix it at 100%;
4 - unplugged the battery cable and kept to unmount it;
5 - after removing the screen frame, and tried back to turn it on, it didnt powered.
Ok this is the situation where i'm stucked on. Now these considerations:
If i plug the phone to the pc, it does get recognized by my device manager under the +Disk devices, as a "Android Android USB Device" (the doubling isn't a mistake). I can't access it, it tells me to insert the disk, even if it's plugged.
If i unplug the battery pin, and plug the phone to the pc, it starts trying to plug in (windows does the typical sound) and then unplug, then again it starts trying to plug, and unplug again... a cycle.. and while it tries to connect, a green led powers on, which turns off and turn on relatively to the cycle phases.
So, what the !&&* is happening? As the screen replacement of this exact model is very very very expensive, i dont know if changing the screen would fix it or if i would just waste my money, which i dont want.
If anybody could help me would be very appreciated.
Thanks in advance