Saturday, January 19, 2013

Samsung Nexus S: Flush Jelly Bean Factory Image

I have been waiting for OTA for several months with no luck. So finally decided to flush my Samsung Nexus S with Jelly Bean 4.1.2 factory image. Here is how I did it. 
  1. (PC) Download Nexus Root Toolkit from here (don't worry. I did not root my phone, just unlocked it for flushing!). 
  2. (PC) Install the software. When prompted, choose your device. In my case, it was Samsung Nexus S, 850MHz, i9020a. Allow the software to download necessary files for your phone.
  3. (PC) Connect your phone to the PC with a USB cable. Run the 'Nexus Root Toolkit' software and click on 'Unlock'. Follow the on screen instructions to unlock your phone.
  4. (PC) Download Nexus S factory image from here
  5. (PC) Unzip the downloaded image in the installation directory of Nexus Root Toolkit. In my case the path was C:\Program Files\WugFresh Development\data
  6. (Phone) Turn off your device 
  7. (Phone) Go to Bootloader (press&hold volume up button then press&hold power button) 
  8. (PC) Go to the folder where you unzipped the factory image. Make sure that the folder contains adb.exe and fastboot.exe.
  9. (PC) Double click on flash-all.bat file. This will flush the factory image in the phone.
  10. (PC) When done, click on 'OEM Lock in the Nexus Root Toolkit to lock bootloader again.
Enjoy your Jelly Bean:)


  1. I have loved your previous tutorials for updates. I'm struggling with this one.

    Around parts 5 to 9 I'm confused. I don't understand when you say go to bootloader. I'm actually worried about bricking and I can't do this because I'm unclear.

    At what points am I using the nexus root toolkit?

    1. Sorry for the late reply. Have you installed 'Nexus Root Toolkit'? If yes, then go to the folder where it was installed. I have added prefix in the steps to show whether the step is for the pc or for the phone. Hope this helps.