Upgrade Sony Xperia Z C6602 / C6603 to Official JB 4.2.2 Firmware [10.3.A.0.423]

Till today, Samsung Galaxy S4 was the only device that was running Android 4.2.2 officially (except Google Nexus phones). But now, Sony has also provided the same (Android 4.2.2) for their flagship device Xperia Z. This firmware update has 10.3.A.0.423 as a build version. It has all the feature that stock AOSP offers and that includes- Day Dream, Photosphere, Actionable & expandable notification bar etc. In addition to that Sony has also added & updated some of their apps. When talking about performance, it’s smoother than Android 4.1.2.

Usually, Sony does take longer time to provide major updates. But now, Sony has proven this statement false by rolling out Android 4.2.2 JB firmware update. And hence, we can say- Soon Sony will be leading the Android phone market as this was the only issue why Sony was lacking in Android Phone market.

So, not discussing so much about the phone market, we’ll see how you can update your Xperia Z to Official Android 4.2.2 Jelly bean firmware.

Disclaimer : Steps given in this article are risky & can cause damage to your device. You should not try to attempt these things if you are unaware of it. Please follow this guide completely at your own risk. We won’t be held responsible if you damage your device while following this guide.

Xperia Z 10.3.A.0.423 Firmware

This guide must be applied only on Sony Xperia Z (C6602 / C6603). Dont try to implement it on any other Xperia device else it may turn in hardware failure of your device.


  • Charge your phone at least up to 75% battery level.
  • It is highly recommended to backup all your data from internal memory (includes contacts, messages (SMS/MMS), call logs, Internet APNs etc.). Your phone data will get lost after installation of this firmware (excluding External storage).

Procedure to Upgrade Sony Xperia Z to Official Android 4.2.2 JB Firmware (10.3.A.0.423):

  • Download Xperia Flashtool from here. Well be using it for flashing the firmware.
  • Download Xperia Z Official Android 4.2.2 JB Firmware package from the link given below (Choose according to your device’s model number):
  1. For Xperia Z C6602 (10.3.A.0.423): Download (Don’t extract)
  1. For Xperia Z C6603 (10.3.A.0.423): Download
  • Install Flashtool that you’ve just downloaded in your computer. For the sake of convenience, install it in root directory of C: drive.
  • Navigate to C: –> Flashtool –> Firmwares and delete all the data over there if anything is present.
  • Now move C6603_10.3.A.0.423_Generic HK.ftf / 6602_10_10.3.A.0.423_TW.ftf’ file in the above mentioned directory.
  • Open Xperia Flashtool. Select Flash option (Black Bolt icon) from the top left corner of the tool (Refer to image given below).
  • It will ask you to select either Flashmode or Fastboot mode. Select Flashmode & proceed further by hitting OK button.

Flashtool Flashmode

  • On next screen, Firmware selection window will appear. On left side, select C6602 / C6603 (version 10.3.A.0.423).
  • In right side of the tool, tick following 4 options (Caution! Dont tick any other option than 4 mentioned below).
  1. Wipe data.
  2. Wipe cache.
  3. Wipe apps log.
  4. No final verification.

Flashtool Flashmode Options

  • Press OK Button. Wait for Flashtool to prepare firmware installation.
  • Now, it will ask you to connect your phone. Before you connect your phone to computer, enter into Flashmode on it. To do so, switch off the phone completely. By holding Volume down key, connect it to PC. If done correctly, you should see a green light on the power.
  • After establishing proper connection with the computer, flashing process will start. Firmware installation process may get stuck around 93%, which is normal. It stays there for 20-30 seconds and not more than that.
  • Once you get Flashing finished message in Flashtool, remove your phone from PC & wait for it to reboot (It may take more time than usual for booting the device, which is normal. So don’t get panic & be patient).

Fantastic! You have successfully upgraded your Xperia Z to Android 4.2.2 Jelly Bean firmware. Now in case if you need any help while flashing firmware, do comment below. Well try our best to sort it out. Enjoy Android 4.2.2 and report how it is working for you!

Comments (5)
  1. jafarkhan July 15, 2013
  2. Salem Zoumot July 8, 2013
  3. hery July 5, 2013
  4. Ahm July 4, 2013
    • Viraj SK July 4, 2013

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