mobile

There are quite a few threads that have all the information but for new Z3TC owners, it can be challenging to know where to start and to understand the process.

How I started here is recently purchasing a Rogers Z3TC and to my surprise, the bootloader cannot be unlocked. I shouldn't have been surprised since carriers do tend to lock the bootloaders and if I did my research, I would have found out that Sony offers unlockable and non-unlockable versions of the same hardware. I have never had to worry about having a recovery to root the device or install custom ROMs with root. For anyone new to Android, the recovery is probably the single most important mode to setting up your device the way you want. A prerequisite for that is of course an unlocked bootloader so you can install the recovery of your choice - ClockworkMod (CWM) or TeamWin Recovery Project (TWRP).

So what makes the process confusing for some new Z3TC owners, such as myself, is that the process is somewhat backward. For most of my previous devices, it is:

1. Unlock bootloader
2. Install recovery
3. Gain root through flashing SuperSU or a rooted custom ROM

Because for my Rogers Z3TC cannot be bootloader unlocked, the process now looks like this:

1. Obtain root
2. Install recovery
3. Flash a pre-rooted Lollipop ROM

The only way we can get root on Lollipop is on a pre-rooted ROM because there is no exploit yet to do it directly. The only way we can install a pre-rooted ROM is through a custom recovery. The only way we can get a custom recovery is to be rooted. For unlocked bootloaders, they can get recovery through flashing the img of the recovery. The only way we can obtain root is through an exploit on a Z3 ROM, which thankfully works on the Z3TC due to the similar hardware.

So without quoting all the instructions of each step, I will provide the links and you just have to follow the instructions for each part.

Before you begin, you will need Flashtool and install the drivers for Flashmode and your device. You will not need Fastboot because unfortunately, you wont be doing anything with it on a locked bootloader. You may install it if you want.

If you are on Windows 8.1/10, you will need to to disable driver signature.

1. Obtain root by first flashing SGP621_23.0.1.A.0.167_CE.ftf and the system partition of D6603_23.0.A.2.93_Generic_20GLOBAL.ftf. Then use giefroot to root.
2. Prepare prerooted flashable zip of 23.1.A.0.690 NOBA on your internal storage or external SD.
3. Install XZDualRecovery and now you will have TWRP to install 23.1.A.0.690 NOBA on your SD card.

I would finish off by running SGP621-RICDefeat.zip to get R/W system access.

This is the simple template that I would imagine be the way those of us with locked bootloaders will install custom ROMs, obtain root or upgrade Android.

Thank you @lowtraxx for the root instructions and @[NUT] for the XZDualRecovery.