How to Root Sony Xperia J on 11.2.A.0.21 Jelly Bean Firmware (Update)

Sony Xperia J was officially released back in October 2012. Xperia J is running Android 4.0.4 Ice Cream Sandwich out of the box and recently received Android 4.1.2 Jelly Bean upgrade. This is the happiest moment for most of the Xperia J users but it might also be the latest cross-version upgrade for Xperia J. Nevertheless, you can always find yourself a highly-customized rom in XDA for Xperia J besides of waiting endless for official update from Sony.

First few days of getting latest Android 4.1.2 Jelly Bean will definitely enlighten you especially with lots of features come along with the update. It does stated that new update will improve the performance as well as to enhance the stability of your device. However, your device will still embedded with stock software/application from carriers. One of the simplest way to eliminate so-called bloatware is by rooting your device. Once you gain full access to the device, you can uninstall these bloatware as simple as you uninstall 3rd party application from Google Play Store.

We provide the complete tutorial for you to root Sony Xperia J on *11.2.A.0.21 Jelly Bean firmware (update). Remember to backup your data in the device to avoid data lose during flashing process. Keep in mind that a single step might brick your device, so follow the tutorial step-by-step. If you in doubt, do not hesitate to leave us a message.

Sony Xperia J features 1.0GHz Cortex A5 processor and 512MB RAM. It also comes with 4GB internal storage with SD card expansion up to 32GB, 5MP rear camera and VGA front camera, 4.0 inches 854×480 TFT display. Sony Xperia J is running Android 4.0.4 Ice Cream Sandwich firmware out of the box and upgraded to Android 4.1.2 Jelly Bean.

How To Root Sony Xperia J on 11.2.A.0.21 Jelly Bean Firmware

Disclaimer: It’s always a risk to modify your device. We, Android Teen are not responsible for any damage or bricks on your device. Your device warranty may void with any mod. Check your devices warranty’s term & conditions before start.(HTC,Samsung,LG, Sony, Motorola). Use this guide on your own risk, contact us for help if you face problem.

Pre-requisites & Requirements

  1. Sony Xperia J – 11.2.A.0.21 Jelly Bean Firmware (Ensure correct device model and firmware; Check device model – Go to Settings -> About Device -> Model Number)
  2. Windows-based computer or laptop
  3. Download Sony Xperia J USB driver for Windows and install in your computer.
  4. Connect device to computer with USB cable to complete installation.
  5. Skip this step if you have installed the USB driver.
  6. Enable USB Debugging on your device. How to Enable USB Debugging Mode on Android Devices.
  7. Make sure your phone is charged to 60% 80% to avoid battery blackout and interruption during this tutorial.
  8. We recommend you make a backup on your data and media files before the tutorial. You may restore the data and files if necessary.

Reminder: Ensure you make a backup before proceed. Besides that, ensure you meet the requirements before proceed. Contact us if you face problem.


  1. Sony Flashtool (flashtool- | 112.77MB)
  2. Root Xperia ( | 1.61MB)
  3. Boot Image (boot.img | 6.77MB)
  4. ICS Kernel ([ICS]kernel.sin | 5.5MB)


  1. Download Sony flashtool into your computer. Double click on the flashtool.exe file to install. You should see a flashtool folder in C Drive.
  2. With your device turned on, connect the device to computer via micro USB cable.
  3. Copy and paste file to your device sd card.
  4. Unplug and turn off your device.
  5. Double click on flashtool icon in the folder mentioned in Step 1 to launch flashtool.
  6. Enter to Fastboot Mode on your device by press and hold Volume Up button while connect your device with USB cable to computer. You should see blue led light.
  7. Download boot.img and copy to flashtool/firmwares folder in computer.
  8. On the flashtool, click on the lightning icon and click fastboot mode, then “ok”.
  9. Click “Select kernel to Flash” on right side in flashtool.
  10. Browse and choose “boot.img” in the flashtool/firmwares. Boot.img will be flashed to your device.
  11. Turn off the device after flashing.
  12. Boot into CWM recovery by pressing Volume Down button continuously while the device is starting up.
  13. From the main menu in Recovery, select the install zip from ext card, then browse to folder location and select the and click Yes to install.
  14. Reboot your device after flashing Root Xperia package.
  15. Download ICS Kernel and copy to flashtool/firmwares folder in computer. Renamed ICS Kernel to “kernel.sin”.
  16. On the flashtool, click on the lightning icon and click fastboot mode, then “ok”.
  17. Click “Select kernel to Flash” on right side in flashtool.
  18. Browse and choose “kernel.sin” in the flashtool/firmwares. ICS Kernel will be flashed to your device.
  19. After the process completes, you may reboot your device.
  20. Download root checker to check your root status.

LIKE us or give us a +1 if it works for you.

A 17 years old young tech enthusiast who loves Android and smartphone. He love to learn and share Android latest technologies to public users. He likes to play around with custom ROM flashing, customize theme, system tweaking and discussion with other developers on Android development. Now, he owns Galaxy S3, LG Optimus L5, Sony Xperia Z and pre-owned Sony Xperia P, HTC One X, LG Optimus G.
  • Pingback: Sony Xperia J: Install ClockWorkMod (CWM) Recovery on Android 4.1.2 Jelly Bean with Locked Bootloader - AndroidTeen()

  • ariel

    what will happen to my phone if ever i did not made it sucessful for the 1st attemp?

    • androidteen

      Most of the time, you won’t see any problems. Bear in mind, follow steps to proceed. Drop us message if you have problem.

  • probal

    my mobile is xperia j. when i was updating my phone with my desktop. in middle time of updating carent had gone. then my mobile do not open fully. it open and see only sony and then again it go to off and then it again start and see only sony in screen. what is happened in my phone and how can i overcome from this problem???

    • androidteen

      hi probal, are you in the way of rooting your device? Or you just update to latest firmware using Sony PC Companion?

  • androidteen

    If you cannot turn on your phone, you need to manually update your device to the latest firmware. We can make a tutorial to teach you how to flash latest firmware on Xperia J using Flashtool.