Posted on May 5 2013 - 1:46pm by Anurag Kumar

Android 4.1.2 Jelly Bean update is rolling out now for many Xperia phones like recently we saw Xperia P LT22i getting android 4.1.2 jelly bean update firmware build number 6.2.A.0.400 on 3.0.8 old kernel version and Xperia Go ST27i also getting android 4.1.2 jelly bean update with same firmware build number and kernel version along with same baseband version u8500-49020911-P3A_EC05. A lot ago Sony made clear that Xperia U will not be getting android 4.1.2 jelly bean update as we know because of hardware limitations. But I can tell you Xperia U users are desperate to get a jelly bean update which unfortunately now not possible.

Bugs in ROM

Xperia Go customized kernel for Xperia U is not full functional at this stage there are many bugs present. We noticed that LED illumination bar is not lighted, neither camera has proper functionality yet. Sometimes phone may go in deep sleep. Touch is not very sensitive and battery drain a issue. So if you don’t wan to take a risk then do not update the below ROM on your phone. Proceed at your own risk, neither developer nor we are responsible for any damage you might cause in your phone.

How to Install Android 4.1.2 Jelly Bean in Xperia U ST25i

Fortunately the recognized XDA Developer munjeni has successfully ported the stock android 4.1.2 jelly bean firmware of Xperia Go on Xperia U with kernel version 3.0.8. The boot image has only been designed for Xperia U so must be tried on on it only, take it as warning.

Android 4.1.2 Jelly Bean in Xperia U ST25i - 3.0.8 Kernel

Installation steps

  • Download the custom boot image of Xperia GO jelly bean firmware.

Download I 16.33 MB
MD5 Sum: 480ecf3be609406b8afabd04fc652c8d

In the above downloaded file you will find the modified ramdisk from Xperia Go new jelly bean firmware and the custom jelly bean kernel version 3.0.8.

  • Download the customized ROM for Xperia U.

Download I 624.7 MB
MD5 Sum : 996ebeeaa473b0eed0a8dde0836662bb

  1. Bootloader on your Xperia U must be unlocked before you flash this image.
  2. Supposing you have unlocked bootloader. Copy the file on your phone.
  3. Flash the “boot.img” file via Flash Tool for Xperia , and after that boot in CWM recovery, install the whole file and the ROM file via option “install zip from SD card”. Done, then. Switch on phone again.

Xperia U Jelly Bean Customized ROM Details

  • App Drawer size is 4×4.
  • AnTuTu benchmark score of Xperia U on Jelly Bean is 6783.

AnTuTu benchmark score of Xperia U on Jelly Bean is 6783

  • Capacitive keys are not working very smooth, they are OK.
  • SMS, Call dialer, lockscreen working smoothly.
  • Fast boot, all connectivity options like Wi-Fi, Bluetooth, GSM working fine.
  • Xperia Home is lagging overall.
  • No small apps, as because of small screen, Xperia P and Xperia Go didn’t get small apps.
  • Battery drain is an issue.

If you are unable to do any step drop us a comment we will gladly help you.

[ Via – XDA ]

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27 Comments so far. Feel free to join this conversation.

  1. Xperia U User May 9, 2013 at 7:07 am - Reply

    As it is ported from JB firmware of Xperia Go so now our Xperia U will posses the same features like which are present in JB of Xperia Go….isn’t there is any hardware conflict issues..

  2. stefy May 16, 2013 at 4:12 pm - Reply

    i do all these steps but after that when i turn on my phone it doesn’t boot anymore…it show only sony logo…..can u tell me what should i do? i try to install 3-4 times and the same problem i have

    • Anurag Kumar May 16, 2013 at 7:28 pm - Reply

      It’s very bad that you are facing this issue. Have you tried removing the battery of phone, do it once, then device should boot. Try it again and again.

      If still not fixed let us know will find another solution.

    • zed sharma July 30, 2013 at 11:44 pm - Reply

      here is the solution
      all u need to go to clockwaork mod then u need to boot it and install the zip .. it will work if it doesnt .. u need to come back to ics.

  3. Mani kumar May 18, 2013 at 11:20 pm - Reply

    I have unlocked my bootloader and downloaded the kernel and ROM for JB..
    My doubt is how to flash boot.img using flashtool.
    Please explain this..

    • Anurag Kumar May 25, 2013 at 2:49 pm - Reply

      Check the info here –

  4. Rajeev May 23, 2013 at 12:25 pm - Reply

    the rom is awsme ……….good but camera is not working…… shows unable to connect camera ………then I flash jb camera it’s also not working plzzzz help

    • Anurag Kumar May 23, 2013 at 12:41 pm - Reply

      Will get back to you soon, with solution, is camera not at all working ??? The JB rom has some camera issue it’s mentioned in the post also but can you please let me know your exact issue.

  5. Kuba June 13, 2013 at 1:36 am - Reply

    Why does the flashtools tell me that “device must be rooted first” when im trying to flash the boot.img? I have root and cwm installed so what is the matter?

    • Anurag Kumar June 14, 2013 at 12:05 pm - Reply

      It maybe some technical glitch, on which firmware you are ?

  6. Tiffiny June 15, 2013 at 6:07 pm - Reply

    Still not able to get it, stuck at booting step, i guess my XU bricked 🙁

  7. jhapendra bashyal July 9, 2013 at 9:29 pm - Reply

    my xperia u is work slower and its battery heated fasted how i fix that problem

    • Anurag Kumar July 10, 2013 at 5:20 pm - Reply

      4.1.2 JB for XU is buggy already mentioned as XU hardware not enough to support JB so they are just it’s side effects of installing JB

  8. kingoboy badis August 3, 2013 at 8:18 pm - Reply

    the camera dosen’t work

    • kingoboy badis August 3, 2013 at 8:21 pm - Reply

      the rom is awsme ……….good but camera is not working…… shows unable to connect camera ………then I flash jb camera it’s also not working

    • Anurag Kumar August 3, 2013 at 8:48 pm - Reply

      there is a bug in camera, already mentioned 😛

  9. muhammad rashid August 15, 2013 at 8:58 pm - Reply

    any kernel flash video tuturial for xperia u via flashtool..

  10. alaa October 28, 2013 at 6:01 am - Reply

    i can’t found any update

  11. braingomes December 13, 2013 at 9:30 pm - Reply

    pls help me .. i already flashboot my xperia U .. now i can open my phone .. its just restr n restr 🙁 .. now how can i copy on my phone ?? pls replyy hurry .. ??

    • Anurag Kumar December 13, 2013 at 9:38 pm - Reply

      You are getting boot loops ? Try to boot into recovery while you see sony logo and then flash it

  12. braingomes December 13, 2013 at 11:05 pm - Reply

    how ? when i se sony logo off n on all time please give me like bro Anurag Kumar 🙁 , how to fix also if u can sent me trial video pls kindly.. i use my brother pc so i cnt use at all.

  13. braingomes December 13, 2013 at 11:07 pm - Reply

    give me link…..***

  14. braingomes December 14, 2013 at 12:54 am - Reply

    wow i did it did it 😀 thnkyou so much bro …. love u guys ….,, i wish if i get android kitkat 😀 please do hurry

  15. shuzz December 25, 2013 at 10:24 pm - Reply

    is it possible to install jb fr Xperia u..nw I hav ics updated frm ginger bird..only 2updates possible know..thn is it safe to install jb..??? tell me quick

  16. Rajat Rastogi March 6, 2014 at 10:44 pm - Reply

    Hello im using xu since a year I usually face problems like hanging & drain of battery in 5 to 6 hrs @ics. Plz guide me with out any rooting, I’ve reset it more than 15 Times????

  17. john April 1, 2014 at 1:19 am - Reply

    Just take the camera out of nanhu 412 jellybean , it works but the video does not

    • john April 1, 2014 at 1:21 am - Reply

      It may work on xperia that you have ,but not on my xperia E

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