HOW TO: Install Android 4.2.1 SuperNexus 2.0 Jelly Bean on Samsung Galaxy S3 I9300
We have put together a detailed step-by-step instructions guide on how to install Jelly Bam 4.2.1 with Android 4.2 Apps custom firmware on Galaxy S3 I9300. If you are used to installing custom ROMs on your Galaxy S3 I9300, then this should not be any different for you.
However, for beginners, you need to root your Samsung Galaxy S3 and install a custom recovery. Please Google that up if you are unsure and make sure you read the tutorial once before actually performing it on your device.
- This tutorial is only for installing Android 4.2.1 SuperNexus 2.0 Jelly Bean ROM on Samsung Galaxy S3 I9300. Please do not try on any other Galaxy S III variants.
- Your phone should be rooted and have ClockworkMod recovery installed from before.
- This tutorial will wipe out all your data. Proceed at your own risk.
- Perform a Dalvik Cache wipe before proceeding from the recovery mode.
- Samsung KIES will NOT detect your phone after installing this ROM because it is a custom firmware.
- Make sure you backup all your data in your phone before proceeding.
Complete Step-By-Step Instructions:
Step 2 – Connect and mount your Galaxy S3 USB memory on your computer using the USB cable.
Step 3 – Now copy/paste the downloaded Android 4.2.1 ROM zip and Google Apps files to your SD card. Make sure the files are in the SD card root (not in any folder).
Step 4 – Then turn OFF your phone and disconnect from the USB cable.
Step 5 – Now to get in the Recovery Mode. Switch ON the phone while pressing and holding Volume Up + Home + Power buttons together. Alternatively, read this: How to Enter Recovery Mode on Any Android Phone.
Step 6 – In ClockworkMod recovery, perform a full data wipe first. Then scroll down to “flash zip from SD card” and press the Power button to select it.
Step 7 – Press the Power button again and select “choose zip from sdcard”.
Step 8 –Now using your volume keys, navigate to the Android 4.2.1 ROM zip file that you copied to your SD card and select it using the Power button. Confirm the installation on the next screen and the installation procedure should start now.
NOTE: Repeat this step for the Google Apps zip file as well.
Step 9 – After the installation completes, go to “+++++Go Back” and reboot the phone by selecting “reboot system now” from the recovery menu. The phone will boot now and it might take about 5 minutes to boot on your first time. So, please wait.
That’s it! Your Galaxy S3 should now have Android 4.2.1 SuperNexus 2.0 Jelly Bean custom ROM installed on your phone! Go to Settings > About phone to verify.
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