Galaxy S2 I9100 Gets Official Android 4.1.2 UHMS9 Jelly Bean Firmware [How to Install]
Galaxy S2 I9100 Gets Official Android 4.1.2 UHMS9 Jelly Bean Firmware

Samsung has recently rolled out its latest Jelly Bean update for Galaxy S2 I9100 users via Android 4.1.2 UHMS9 official firmware release. The firmware is now available for download via Samsung KIES and also as an Over-The-Air (OTA) update. However, the Galaxy S2 users who missed the twin opportunities can now download and install the same manually using this guide.

The I9100UHMS9 firmware reportedly brings a handful of bug-fixes without any major feature upgrade over its previous iteration. Though this is a branded firmware with extra language packs and preloaded apps, it can be installed on any unlocked Galaxy S2 I9100 (except in China, Hong Kong and Taiwan).

New Features of Android 4.1.2 UHMS9 Jelly Bean ROM

Here is the list of new features supported by this ROM:

  • Buttery smooth performance and great stability (Thanks to Project Butter)
  • Full user interface revamp (Same UI as of the Galaxy S3 and Galaxy Note 2)
  • TouchWiz Nature UX
  • Samsung's S Cloud services
  • New lockscreen with many customization options
  • New features like direct call, smart stay and pop-up play
  • New widgets (From Galaxy S3)
  • Free 50GB Dropbox Storage
  • 2 Home screen modes
  • New notification bar with more notification toggles
  • Google now

Key Points to Note

  • Android 4.1.2 UHMS9 official firmware and the instructions given in this guide are compatible with the international variant Galaxy S2 I9100 model only and will not work with any other device. Verify the device's model number by navigating to Settings > About Phone.
  • Verify that the correct USB drivers are installed for the Galaxy S2 on computer (download Galaxy S2 I9100 USB drivers)
  • Backup important data and settings on the phone using one of the recommended custom recovery tools such as CWM or TWRP recovery, as it creates a complete image of the existing phone setup.
  • Ensure that USB Debugging mode is enabledon the phone by navigating to Settings > Developer Options (if the device is running Android 4.0 or later) or go to Settings > Applications > Development (if the phone is running Android 2.3 or earlier). Otherwise, if the device is running Android 4.2, then perform the following steps:
    • Go to Settings > About Phone
    • Scroll down to the bottom of screen and select Build Number
    • Tap the Build Number seven times to unlock or reveal the hidden Developer Options under Settings. Then select the checkbox to enable USB Debugging mode under Settings > Developer Options.
  • Make sure that the device has at least 85 per cent battery charge
  • Verify that the phone is factory unlocked (not locked to a specific carrier) and rooted with ClockworkMod (CWM) recovery installed on it.
  • The instructions provided in this guide are meant for reference purpose only. IBTimes UK will not be held liable if the device is damaged during the firmware installation. Users must proceed at their own risk.

How to Install Official Android 4.1.2 UHMS9 Jelly Bean Firmware on Galaxy S2 I9100

Step 1 - Download Android 4.1.2 I9100UHMS9 official firmware for Galaxy S2 on computer and extract the zip file.

Step 2 - Download ODIN v1.85 which is required to install Android 4.1.2 UHMS9 Jelly Bean firmware on Samsung Galaxy S2 I9100.

Step 3 - Power off the phone and boot it into Download Mode. To do so, press and hold Volume Down and Home buttons together, and then tap the Power button until the construction Android robot icon with a triangle appears on screen. Hit Power button again to confirm entry into Download Mode.

Step 4 - Launch ODIN on computer and connect the phone to it while the phone is still in Download Mode.

Step 5 - When the phone connects successfully, one of the ID: COM boxes indicates yellow with the corresponding COM port number. This step may take some time. So, please be patient.

Step 6 - Now, choose the files that need to be flashed or installed on the phone, which can be found among the extracted files in Step 1.

  • Click on 'PDA' checkbox and choose the file named '.tar'.
  • Tap on 'Phone' checkbox and choose the file named 'MODEM'. Ignore this step if there is no such file.
  • Hit the 'CSC' checkbox and click the file named 'CSC'. Ignore this step if such file is missing.
  • Click on 'PIT' checkbox and choose the .pit file. Ignore this step if such file is absent.

Step 8 - In ODIN, enable Auto Reboot and F. Reset Time options. In case of the Re-Partition option, check it ONLY if the .PIT file was chosen in the previous step.

Step 9 - Now hit Start button in ODIN and the ROM installation process will begin. It will take just a few minutes to complete.

Step 10 - Once the ROM installation completes, the phone will automatically reboot. When the home screen appears, disconnect the phone from computer.

Congratulations! Samsung Galaxy S2 is now successfully updated to Android 4.1.2 UHMS9 Jelly Bean official firmware. Go to Settings > About Phone to verify the firmware version installed.

Also, check out our step-by-step guide to Root Galaxy S2 I9100 on Official Android 4.1.2 UHMS9 Jelly Bean Firmware

[Source: Team Android]