[Xperia SP Q&A, Help & Troubleshooting] zedex39zeo:
I feel like this is going to be a long thread but I'll make it short as much as possible with as much details

I have a SONY Xperia SP C5303 stuck in a boot loop, it was given to me by a friend.

The phone was on stock firmware, android 4.3, unrooted, bootloader locked.

As he was using the phone while charging, he activated WiFi, after a while he activated Bluetooth (WiFi and Bluetooth at the same time) and then it just turned off, rebooted and stuck in the "SONY logo => Xperia logo=> Orange logo" boot loop and then it just fades away and blacks out and reboots.

After many attempts, he wasn't able to fix it and he gave it to me .

Now the first thing I did was flashing it using FlashTool with the firmware "C5303_12.1.A.1.207_AU" but still stuck on boot loop, the only thing that happened is that the Orange logo changed into the colorful waves animation.

I flashed it a couple of times more, the same method, but still, the same results.

Next thing I did, I updated it using SONY PC Companion, after the update finished, it was still in boot loop (ALTHOUGH, the lock screen DID appear but I was not able to do anything, and the screen faded away again)

So, I sent it to a repairer, here's what he have done :

_ He did something (?) and gave it back to me with 0 charge, so I charged it at home and when I turned it on, still boot loop, so I returned it to him.

_ This time, it ACTUALLY worked ! The phone came back to life, everything was working just fine, until I activated WiFi and I noticed that it's not working, then I activated Bluetooth as well (AT THE SAME TIME, remember what I said at first ?) then the screen just faded away and back to boot loop, I sent it back to the repairer and told him that he hasn't changed anything and that the real issue is that WiFi and Bluetooth do not work/cause boot loop when working at the same time

_ He revived the phone once again but the WiFi/Bluetooth issue was not fixed and he told me that there's nothing he can do anymore, and he refunded me.

I can't complain though cause all I wanted was the phone working !! I didn't care less about WiFi nor Bluetooth.

This morning, as I wanted to root the device, I tried the DoomLord Easy Rooting Toolkit, after flashing the first kernel using FlashTool (Yes, I followed the steps VERY carefully) and after the flash of the kernel finished, the phone is once again in boot loop, this time boot looping on the SONY logo only

So the conclusion is that the phone can actually be revived. How ? That's what I'd kill to know !! (Jk)

I tried flashing again the "C5303_12.1.A.1.207_AU" (4.3) but nothing, then I tried the previous firmware (4.1) but still nothing.

Sometimes, after the flashing, when the phone boots for the first time, the lock screen appears but fades away again (unable to touch anything)

SO PLEAAAAAAASE !! If there's anything I can do, please tell me, all I want is for the phone to work, hell to the data or anything else, also don't mind the warranty at all. And I'm not from the US, so there are no SONY service points here :p

There's a video in the rar file attached down there, it shows how the boot loop happens.