Going back to stock

[ImperialPM]

Hi guys. I customized my Xperia Z C6602 quite a while ago now, may be 5 years ago. Screen broke at that time, and I bought another phone as I couldn't buy another screen. Now I've managed to get a new screen and replaced it, and I want to sell this phone, but it's still customized, and I don't remember like anything that I did. I want to go back to stock.

I was about to follow the [GUIDE] How to revert your phone from CM/AOSP/AOKP/PAC to STOCK, but I read it could be "overkill", and so I though it would be better to ask. Let me tell you what I have right now:

CyanogenMod Version: 12.1-20150803-UNOFFICIAL-yuga
Compilation Number: cm_yuga-userdebug 5.1.1 LMY48G 1fba35b830
Core Version: 3.4.0-cm-ge347aa9-00481-ge09347c

Xperia Compannion says it won't restore because it's unlocked bootloader. Emma doesn't recognize the phone (I think it only works for C6603, not C6602). I can't think of others "official" ways to go back. Should I follow the revert guide? Or what should I do?

Thanks you very much in advance!!

 

[sarkzkalie]

Using Flashtool then

 

[AasimAmor]

I had fresh experience with going back to Stock.
Download and Install Flashtool.
Download Stock 4.4.4 ftf
Download Stock 5.1.1 ftf.
1.Put your phone in Flashmode(powered off;while connecting usb to pc,hold Vol Down button,it should flash Green light,also Flashtool should say 'Device connected in Flashmode')
2.Flash Stock 4.4.4 ftf(download ftf based on your region,or your phone original firmware).
3.Check if its bootup to 4.4.4
4.Now again put phone in flashmode
5.Flash stock 5.1.1. ftf
6.Done,you are on Stock now.

Now why to flash 4.4.4 first??
Reason-If you flash directly 5.1.1,the phone wont boot after bootlogo,just black screen.I don't know what causes it,but all have experienced it here.
So this the only way to get back to stock rom.

 

[AasimAmor]

Link for Stock ftf you can find in the forum.Use the search function
4.4.4-10.5.1.A.0.283
5.1.1.-10.7.A.0.222/228