The new Android 4.1.2 JZO54K firmware update is here and you can learn how to manually update your Google Nexus 7 by reading this entire post. Google announced today they will launch a brand new 4.1.2 Jelly Bean update for the Nexus 7 and you should note that this update will bring several tweaks and support for the home screen landscape mode, a feature that was requested by all Nexus 7 users.

Use this tutorial and learn how to manually update your tablet. Note that first thing that you need to do, is to read the preparation guidelines and learn how to properly configure your device so that you'll manage to update at your first attempt.

This guide is destined to be used by those Nexus 7 users that are still waiting for the OTA Update notification to be pushed out. Now that you don't want to wait for the OTA notification, then you can use this post and learn how to install the Android 4.1.2 on your Nexus 7 using only the CWM Recovery image. Note that your device should have its bootloader unlocked.

Now that you've read all of the above, I think that you should move to the preparation guidelines and learn what you need to do before beginning to install this new Jelly Bean on your Google / ASUS Nexus 7 tablet. Here's what you need to know:

  • Install the JZO54K 4.1.2 Jelly Bean update only on the Nexus 7 tablet. Do not attempt to flash the files you find in this post on any other devices, as you might end up bricking them.
  • The Nexus 7 tablet should be on an unlocked bootloader. In case your device doesn't have an unlocked bootloader, then you should know that your device will lose all data if you unlock it. Create backups of all files so that you will be able to restore them back on your device after the unlock process is complete.
  • Root isn't necessarily needed as you can use the CWM Recovery on un-rooted Nexus 7 tablets, too. However, your
  • Move all your important files on your device's internal sdcard. This update shouldn't delete any file from your device, but in case you don't want to risk anything, then you can choose to backup your most important data.
  • Make sure that your tablet's battery power levels are over 40% so that it won't power off in the middle of the updating process.
  • Note that we cannot be blamed in case something goes wrong and you lose any data in the process. Also, the chances for your device to be bricked are slim but you should still know what you're doing. That's why you shouldn't attempt to flash this update if you're a novice.

I think that these are all the extra instructions you needed before moving to the tutorial. So, if your device is a Nexus 7 running on an unlocked bootloader then you can move to the next part of this article and learn how to upgrade to the latest Google Android OS firmware.

How to update Google Nexus 7 to Android 4.1.2 Jelly Bean build JZO54K:

  1. Download the JZO54K zip firmware file from HERE. Save the file on your computer and do not extract its contents.
  2. Now, connect your tablet to your PC using the USB cable. Move the ROM zip on the Nexus 7 internal sdcard. Disconnect the device from PC after the transfer is complete.
  3. Power off your Google Nexus 7.
  4. Boot into CWM Recovery mode. Do it by pressing simultaneously 'volume up' + 'volume down' + 'power' buttons. Release the buttons after the tablet's screen powers ON. Use the volume button and select 'CWM Recovery' mode to boot.
  5. When you're at the main recovery screen, select 'install zip from sdcard'.
  6. Next, select 'choose zip from sdcard' and then browse for the 'JZO54K' ROM zip file. Confirm its installation.
  7. After the update process is complete, you should return to the main recovery screen.
  8. Select the option that says 'reboot system now'. Your Nexus 7 tablet will restart and it will perform its first boot with the latest Android 4.1.2 stock Jelly Bean firmware.
  9. Note that the first boot process will take almost 5 minutes to complete and you should wait until that happens. In case this takes move than 10 minutes, then you should power off your device and then repeat the entire process once again, as you will eventually manage to flash the update with success.
  10. When the boot is complete you should see the Android 4.1.2 JB home screen. Take control over your tablet and begin testing the new firmware to discover all the new tweaks and functions added by it.

That's it, you've managed to successfully flash the new Jelly Bean JZO54K 4.1.2 build firmware on your Nexus 7.

If you have any other questions, post them at the end of this post in the comments section.

shonangreg · 6 years ago

I let the OTA update happen and set SuperSU to protect itself beforehand. At reboot, cwm asked if I wanted to reboot, I said yes. Then it asked, "Are you sure? You might lose root." or something like that. I decided to hold off and chose, "go back." It then asked again, "Really sure. You might lose your recovery image." Huh? I said no. Again, "Go back." Then, it rebooted!

I lost root.

So I just went through the same reboot into recovery, pushing SuperSU, installing cwm and SuperSU, and rebooting that I did under 4.1.1. I have root back again with no discernable data loss.

I wish all devices had drivers like this Nexus 7. My Galaxy Note just won't connect to Kies -- on two different computers (one 64-bit Windows 7 and one 32-bit virtual WinXP.)

Pali · 6 years ago

For JRO03S doesnt work . . . why ????

corner-left-up dots-three-vertical