Following the availability of Nexus 4 and Nexus 10, Google has begun the rollout of Android 4.2 Jelly Bean OTA update for Galaxy Nexus and Nexus 7 as well. Android 4.2 is currently available only for the Takju variant of GSM/HSPA+ Galaxy Nexus and luckily Google has also released the Android 4.2 factory image for Takju Galaxy Nexus. Apparently, Non-Yakju Galaxy Nexus users won’t receive this new update anytime soon as their phone is updated by Samsung whereas Yakju & Takju firmware are updated directly by Google. However, users with adequate technical know-how can easily convert their non-yakju (yakjuxw, yakjuux, yakjusc, yakjuzs, yakjudv, yakjukr and yakjujp) device to Takju to receive prompt future OTA updates from Google.
Install Yakju or Takju? Takju, the firmware that ships with the Google Play Store version of Galaxy Nexus (in the US) receives updates faster than the Yakju variant. So, it’s better to choose Takju over Yakju.
1. This process requires unlocking the bootloader which Completely Wipes your device including /sdcard. So make a backup first.
2. Your Galaxy Nexus device name should be maguro (See how to check that)
3. This procedure is meant only for GSM/HSPA+ Galaxy Nexus.
Tutorial – Converting Yakjuxw (Non-Yakju/Yakju) Galaxy Nexus to Takju and updating to Official Android 4.2
Step 1 – This is an important step. You need to install and configure the ADB and Fastboot drivers on your Windows system. Refer to our guide: New Method – Installing ADB and Fastboot Drivers for Galaxy Nexus on Windows 7 & Windows 8.
Step 2 – Take a backup of your installed apps (with data) and SD card contents. Check our article, [How to Backup Galaxy Nexus Apps & Data without Rooting]. Taking a backup of apps is optional but it’s recommended to manually backup your SD card data.
Step 3 – Download and Extract all the required files.
– Download 4.2.1 (JOP40D) Official “Takju” factory Image (Direct Link)
– Extract the above .tar file to your desktop using an archive program like WinRAR. Then rename the file and add a .zip extension to it. Extract the file to a folder on your desktop. Then open the folder and extract the file (image-takju-jop40c.zip) to the same folder. Now you should see 6 files with a .img extension as shown in the image below:
– Download Fastboot & ADB – Extract the zip, then copy and paste all the extracted files to the folder where all the 6 .img files are present, such that all the required files are placed in one single directory. Refer to image:
Video tutorial for Step 3 –
Step 4 – Proceed with Unlocking Bootloader and Flashing Android 4.2
- Turn off your phone. Then boot it into bootloader/fastboot mode by holding the Volume Up + Volume Down key and power key simultaneously.
- Connect the phone to the computer using a USB cable.
- Now Right-click the folder ‘takju-jop40c’ while holding down the Shift key and click on ‘Open command window here’.
- A command prompt window will open up. Type fastboot devices to confirm that your device is recognized while it’s in fastboot mode.
Unlock Bootloader – Unlocking the bootloader will wipe the entire data on your device including SD card. So, make sure you’ve taken a backup of your important files.
In CMD, enter the command fastboot oem unlock . Then a screen titled ‘Unlock bootloader?’ will appear on your phone. Select ‘Yes’ to unlock (use the volume keys to navigate and the power key to make your selection.) The lock state should say Unlocked.
Flashing Android 4.2 Takju Manually –
When your device is in fastboot mode, enter all the below commands step-by-step in the stated order (use copy-paste in CMD to input the command).
Note: Make sure to wait for the “finished.” notification in CMD before entering the next command. The system.img and userdata.img file takes a bit longer to flash.
fastboot flash bootloader bootloader-maguro-primelc03.img
fastboot flash radio radio-maguro-i9250xxlh1.img
fastboot flash system system.img
fastboot flash userdata userdata.img
fastboot flash boot boot.img
fastboot flash recovery recovery.img
fastboot erase cache
That’s it! Your device should now boot up normally with the new Android 4.2 update and ‘Takju’ firmware that will offer faster updates directly from Google.
Disclaimer: Try this guide at your own risk! We wont be responsible in case your device gets bricked. This may also void your warranty.