In my case the sd led never flash!!!
The power led is flashing endless and after reboot i'm always in the messed state (the circular arrows continuosly turn until I press reset or reboot).
rupor suggest me to manually overwrite the partition using a fresh image but: I can't figure out how to use the script that he suggest me to extract the image from the sony upgrade file and the where I should "dd" it in which device?
I think to use the update.img from your sd_rescue (I try also the last one but it behaves like the previus, that is, it doesn't do nothing in my case) but it's size seems strange to me, but I may misunderstand something (this i sure).
Any idea on how to manually force (with a key sequence) the "data transfer mode" of the reader?