Update Galaxy S2 I9100 to XWLSS Android 4.1.2 Jelly Bean Official Firmware

Samsung Galaxy S2 I9100 starts with Android 2.3 Gingerbread ROM but you can now update Galaxy S2 I9100 to  XWLSS Android 4.1.2 official firmware update. This is the latest firmware released earlier today for this Android   phone. Like always, we have the tutorial on how to install this firmware on your phone with the most easy instructions. For those who are not able to download this update from Samsung KIES, you can always grab the latest update for Galaxy S2 and the tutorial from MyTrickSource. You do not need to have ClockworkMod recovery installed or a rooted phone in order to install this update manually. You can easily update  Galaxy S2 I9100 to  XWLSS Android 4.1.2 using our tutorial.

As you continue reading, we will guide you through the entire process of how to install XWLSS Android 4.1.2 firmware on Galaxy S2 I9100. Please make sure you backup your data with the given tips below and also read the other
important tips given as you will need them before proceeding to the update tutorial. This is an unbranded firmware so it can be installed on any Galaxy S2. Let’s continue with the tutorial below.

Disclaimer: All the Custom ROMs and firmwares, official software updates, tools, mods or anything mentioned in the tutorial belong to their respective owners/developers. We (MyTrickSource) or the developers are not to be held responsible if you damage or brick your device. We don’t have you on gun point to try out this tutorial ;-)

Android 4.1.2 XWLSS Firmware Details:

Version: 4.1.2
Date: 2013 May
Regions: United Kingdom / Ireland

Latest ROMs Updates for Galaxy S2 Series in MyTrickSource:

Samsung Galaxy S2 USB Drivers

You will need to connect your Android phone with the computer. For that, please make sure you have installed the USB drivers for Samsung Galaxy S2  properly. If not, you can download the latest official drivers from our Android USB Drivers section here:
Download Samsung Galaxy S2 USB drivers!

Backup and Other Important Tips

Done with the USB drivers? Perfect. The tutorial is on the next page, but first, please take a look at the following tips and important points you need to take  care of. These are important, as we don’t want anyone losing their personal data or apps:
Always backup your important data that you might need after you install a new custom ROM, an official software update or anything else. Make a backup for just in case, you never know when anything might go wrong. See below for some tips on how to backup data:

Samsung users can also back up data using Samsung KIES. If you backup data manually, you get more options what to choose from and it is very easy to move data across Android devices from different manufacturers, i.e moving Samsung Galaxy Note backup data to HTC One X.

    If you already have a custom recovery (ClockworkMod, TWRP etc.) installed on your phone, we strongly recommend a backup using that as it creates a complete image of your existing phone set up.

A few more optional tips that you should remember:

        1. Having problems connecting your Android phone to the computer? You need to enable USB debugging mode.

        2. Make sure your Android device is charged up to 80-85% battery level. Why? Because, if your phone goes off suddenly while installing a custom ROM, flashing an official firmware update or installing mods etc. — your phone might get bricked or go dead permanently. No one wants that, right?

        3. Most of the tutorials and how-to guides on MyTrickSource are for factory unlocked Android phones and tablets. We recommend NOT to try our guides if your phone is locked to a carrier, unless we have specified the carrier name or device model.

If you find the above tips useful and they were helpful to you, please consider giving us a +1 or LIKE to thank us!

All set and ready? Now, let’s proceed with the tutorial below and update Galaxy S2 I9100 to XWLSS Android 4.1.2 Jelly Bean Official Firmware.

How to Update Galaxy S2 I9100 to XWLSS Android 4.1.2 Jelly Bean Official Firmware

We have put together a detailed step-by-step instructions guide on how to update Samsung Galaxy S2 I9100 to Android 4.1.2 XWLSS Jelly Bean If you are used to installing official updates through ODIN on Samsung Galaxy  devices, then this should not be any different for you.Please read every line carefully and make sure you read the tutorial once before actually performing it on your Android device.

To Remember:
  • This tutorial is only for Samsung Galaxy S2 I9100  Please don’t try this on any other variants of the phone.
  • This is an unbranded firmware with no carrier apps installed on it.
  • Make sure you backup all your data in your phone before proceeding.
Rooting Warning: This is an official Android 4.1.2 Jelly Bean update for Galaxy S2 I9100, which means you will lose root as soon as you install this update. You will again have to root Galaxy S2 I9100 to gain full system access and be able to install root apps again. 

Step-By-Step Instructions:

Step 1 - Download XWLSS Android 4.1.2 Jelly Bean for Galaxy S2 I9100 to your computer and extract the zip file.

Step 2
 - Download ODIN v1.85 which will help you to install Android 4.1.2 on Samsung Galaxy S2 I9100.

Step 3 - Switch OFF your phone. Now go to Download Mode. How? Press and hold the Volume Down + Power buttons together, till you see the Samsung logo or the construction Android robot and a triangle. This is the Download Mode.

Step 4 - Make sure you have your Galaxy S2 USB drivers installed on your computer.

Step 5 - Open ODIN on your computer. Connect Galaxy S2 to your computer while the phone is in the Download Mode.

Step 6
 - If your phone is connected successfully, one of the ID:COM boxes will turn yellow with the COM port number. This step might take some time.

Step 7
 - Now select the files that you have to flash/install on your phone. These files are to be found from the extracted files in Step 1.

  • Click on ‘PDA’ and select file with ‘CODE’ in its name.
  • Click on ‘Phone’ and select file with ‘MODEM’ in its name. Ignore this step if there is no such file.
  • Click on ‘CSC’ and select file with CSC’ in its name. Ignore this step if there is no such file.
  • Click on ‘PIT’ and select the .pit file. Ignore this step if there is no such file.
Step 8 - In ODIN, check the Auto Reboot and F. Reset Time options. As for the Re-Partition option, check it ONLY if you selected a .PIT file in the above step.

Step 9 - Now click on the Start button in ODIN. Installation process will start and would take a few minutes to complete.

Step 10 - After the installation is completed, your phone will restart. After you see the home screen, unplug your phone from the computer.

That’s it. Your Samsung Galaxy S2 I9100 has now been updated to XWLSS Android 4.1.2 Jelly Bean Official Firmware. Go to Settings > About phone to verify.

Hit +1 or LIKE to thank us!

Need Help?

If you run into any problems during Updating Galaxy S2 I9100 to XWLSS Android 4.1.2 Jelly Bean Official Firmware, feel free to drop us a comment below and we will reply you back ASAP with the fix or the solution to your problem.


  1. Im quite new to this ODIN flash thing, im a user in Malaysia, will this work on my i9100?

    1. AslamuAlaiKum Khairul Ridzwan

      Sure, it will perfectly work in I9100

    2. My GS2 phone is Rooted and locked so can i do this? Thanks

    3. My GS2 phone is Rooted and locked so can i do this? Thanks

  2. I did all of this exactly yesterday. About phone says
    Android Version 4.1.2 Baseband I9100XXMS2
    Kernel Version 3.0.31-1146082
    SMP PREEMPT Mon Apr 22 16:13:38
    KST 2013
    Build Number JZ054K.I9100XWLSS
    This is all identical to my wife's phone which got the update OTA on Sunday. Mine was a branded O2 phone (which was rooted), and never received any updates, so I Odin flashed mine yesterday.

    Kies will not detect my phone- is that normal? It has not been re-rooted.

  3. Hi..i have a 2.3.6 Optus Unlocked S2. Can I just flash the 4.1.2 directly through Odin or do I need to flash ICS first>