Hi,
Apparently this is a more frequent issue than I'd have thought.... A relative of mine brought me his M4 Aqua e2303 with the same symptoms: it tries to boot, shows the Sony Logo (Xperia on the bottom of the screen) and it just loops. Screen goes off-then-on and the same thing. I've tried EVERYTHING. Bootloader was locked, so as a desperate measure I even unlocked it via Flashtool. First I tried Sony PC Companion App and automatic repair. It went smoothly but the phone was still stuck, then I flashed the last ROM via Flashtool. Again, everything went OK, but the phone was still stuck. I flashed a different ROM, the European Press version, since it's a little bit older, and suddenly something changed. The boot sequenced advanced from the Sony Screen to the waves screen, even with the music, but it just freezes and reboots itself 3 or 4 seconds after the blue-ish waves screen appears and the melody starts playing. Fastboot works, and I even pushed a custom recovery image. It boots, works, touchscreen and everything, and I can wipe everything (which I even did) but to no positive result. I've read about theft protection bricking some M4 Aqua phones, but this one had a locked bootloader, so it's out of the question (I think)
I'm absolutely dumbfounded... the only thing that comes to mind at this point is a hardware failure. My relative got the screen replaced, but everything was working fine after that, so I guess some cable/ribbon/whatever could get loose over time? Any idea?
I've learned a lot reading this thread and XDA Dev generally. Thanks, guys, great community.
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