[Sony Xperia Z Ultra] zxc1251:
Updated - 6/2/14 - To reflect suggestions by - [MENTION=3534362]blueether[/MENTION] - [MENTION=1655514]maxld[/MENTION] - [MENTION=5883705]polargirl[/MENTION] - Thank you all.

This might help someone Noob like me.

This is primarily written for my C6806 however steps are similar for other z ultra devices.

Everything here is copied from other threads on this forums and Google search. I have tried to provide links to threads as much as I can.

For anyone following these steps

Please do more research on each steps.

This steps should give you clear idea as to what is involved in this procedure

You must follow steps from top to bottom for this to work.

Check Bootloader Status

Dial *#*#7378423#*#* or download this app from playstore to directly go to Service Info

Go To Service Info > Configuration > Rooting Status

If you see Bootloader Unlocked: Yes, that means your phone is bootloader unlocked

if you see Bootloader unlock allowed: Yes continue with steps.

if you see No above do not continue any further, STOP

Disable Signed Driver Enforcement on Windows 7, 8, 8.1 (This is a must step)

Reboot your computer while pressing F8

Select "Disable Driver Signature Enforcement" and press Enter

Install FlashTools and FlashTools Drivers

Download FlashTools from following link (You must use latest version)

http://www.flashtool.net/download.php

Install FlashTools

Go to Flashtool\drivers install Directory

Double Click Flashtool-drivers.exe

Select Flashmode, Flashboot, z ultra (all), xperia A and click Install

Flash 14.1.B.1.532 ftf file to phone (For locked or unlocked phones - Thanks [MENTION=3534362]blueether[/MENTION])

Start Phone Normally

Go to Settings

Click ten times on Build Number to enable developer options

Go to Settings -> Developer options and enable USB Debugging

Go to Settings -> Security and enable install from unknown sources

Turn off phone

Download C6833_14.1.B.1.532_NUT.ftf File from this thread http://xdaforums.com/showthread.php?t=2593918

or Download Directly from here http://xdaforums.com/devdb/project/dl/?id=3442

Extract zip file downloaded above

Copy ftf to Flashtool\firmwares directory

Open FlashTool

Click Flash (lightning bolt icon)

Select FlashMode and click ok

Select the above file from left side and click flash

When Asked by FlashTool, keep holding vol down key connect phone to computer with usb cable

Disconnect phone (After FlashTool finish installing firmware file)

Restart phone

Root with Bin4ry method

Download Root_with_Restore_by_Bin4ry_v33 file from this thread http://xdaforums.com/showthread.php?t=1886460 or direct link http://uploaded.net/file/d2w6dl7r

Follow this video for more detailed instructions https://www.youtube.com/watch?v=7EpkrCq1gfM#t=149 or continue with next step

Start Phone and enable usb debugging and install from unknown sources options.

Extract above Root_with_Restore_by_Bin4ry_v33.zip file to c:\ drive

Double Click the RunMe.bat and follow instructions

Select - Xperia phones with “older” firmware option when asked

Backup TA Partition

User this video for more help https://www.youtube.com/watch?v=kva9-rAPG5s

Download Latest Backup TA for Sony Xperia tool from this thread http://xdaforums.com/showthread.php?t=2292598 or direct link https://github.com/DevShaft/Backup-TA/releases

Extract downloaded file to c:\

Start phone

Run Backup-TA.bat

Follow instructions on screen

After backup store entire Backup-TA directory at safe location for some future use

Flash 14.3.A.0.757

Download 14.3.A.0.757 file

For C6806

Download US Retail/Generic C6806 14.3.A.0.757 file from this link http://d-h.st/4vv

For other version of z Ultra

Go to this thread and download appropriate 14.3.A.0.757 ftf file http://xdaforums.com/showthread.php?t=2453921&highlight=757

Extract this zip file

Copy C6806_14.3.A.0.757_1276-1569_R3C.ftf (for C6806) to Flashtool\firmwares directory

follow steps similar to “Flash 14.1.B.1.532 ftf file to phone”

Unlock Bootloader (Please read more before doing thess steps, I might have missed many things here)

Reference Post you would like to read, http://xdaforums.com/showthread.php?t=2447319

Write down IMEI code for your device

dial *#06#

Write displayed IMEI and save it at safe place

FlashTool method to unlock bootloader

Start FlashTool

Click on BLU button

Connect phone in flashmode as per the instructions on screen

Once Connected click unlock

When prompted disconnect the device

ROOT 14.3.A.0.757

Instructions from Thread http://xdaforums.com/showthread.php?t=2714511

This works for all c68xx devices with 14.3.A.0.757 firmware

Download kernal from this link

https://mega.co.nz/#!Vh8xEZYR!HwGosIRT1wFVCwm80KjL6vbo0NSduVlhUObM0NdNrPg

Download SuperSu from this link

https://mega.co.nz/#!t18y2SRb!WwXemirwFBTqpxeNYrJJLC1jwH7R13NQE-uU7yEBk2Y

Help video https://www.youtube.com/watch?v=uFSeSe8gQOY

Start Phone Normally

Copy Above SuperSu.zip to internal or external SD Card

Go to Settings

Click ten times on Build Number to enable developer options

Go to Settings -> Developer options and enable USB Debugging

Go to Settings -> Security and enable install from unknown sources

Turn off phone

Disconnect USB cable

Press and hold vol up button and connect USB cable to phone and PC, wait until led light turns blue

Start FlashTool

Click Flash (Lightning bolt)

Select Fastboot mode and click ok

Click Select kernel to Flash

On File chooser window change *.sin to *.img

Select above 757.img file and click ok

on FlashTool window if it says sending boot ok do not worry about any other errors

Disconnect USB cable

Go to Recovery

Press power button to start phone

As soon as you see sony logo press and hold vol down button

This will boot you into recovery

Click Install on Recovery screen

Select SuperSu.zip file uploaded earlier (from internal or external sd card)

Swipe to confirm

Click Reboot System

That is it finally you have your xperia z upgraded and rooted.