While the list is being plotted, Samsung had rolled out the stock build Android 4.3 Jellybean to its Galaxy S3 users. It has a base firmware of I9300xxUGNB4 which is meant for the Galaxy S3 international version, GT-I9300.
More details of the firmware are as follow:
Model: GT-I9300
Version: Android 4.3 Jelly Bean
PDA: I9300XXUGNB4
CSC: I9300NZCGNB1
MODEM: I9300XXUGNB1
Build date: 17 February
If you’re using the Galaxy S3 GT-I9300, then feel free to perform the update with the guide below. After all, it will fix the many issues that are plaguing the device at the moment.
Pre-requisites
1) Install USB Drivers for Samsung Galaxy S3 to connect the Android device with the computer.
2) Enable USB Debugging Mode on phone to connect it with the computer and use Android SDK with it. [Navigate to Settings>> About phone. Tap on Build Number several times until a message appears saying ‘You are now a Developer.’ Now go to Settings>> Developer Options to enable USB Debugging Mode.]
3) As the tutorial is likely to wipe out all data of the phone, create a backup. If the device is having any custom recoveries such as CWM/TWRP then backup data using the same.
4) If the Android phone powers off due to lack of battery while the installation process, it could damage the device. Therefore, the Galaxy S3 should have charge above 80% battery charge.
5) The device should be factory unlocked and not locked to a particular carrier.
6) The phone will lose custom ROM with the installation of official firmware. Also, the custom recovery will be replaced by the stock version.
7) The device will no longer belong to a rooted version with the installation of official firmware.
8) I9300XXUGNB4 Android 4.3 Jelly Bean official firmware works only with Samsung Galaxy S3 GT-I9300. As flashing this on any other variant might brick the device, verify the model number of Galaxy S3 by navigating to Settings>> About device>> Model number.
Flashing instructions
Step-1: Extract the downloaded firmware zip using winrar/7zip/winzip or any other extracting tool to get a .tar.md5 file with few other files, which are optional
Step-2: Extract the Odin zip to get Odin3 v.3.07.exe with few other files
Step-3: Switch off Galaxy S3
Step-4: Place the phone into Download Mode by pressing and holding Volume Down, Home and Power buttons together until a construction Android robot icon with a warning triangle appears on the phone screen. Now press the Volume Up button to enter Download Mode
Step-5: Run Odin3 v3.07.exe as Administrator [To do so, right click on Odin.exe file then click on Run as administrator from context menu.]
Step-6: Connect the Galaxy S3 to computer using USB cable while it is in Download mode. Wait for some time until Odin detects the device. When the phone is connected successfully an Added message will appear under Odin. Also, the ID: COM box in Odin will turn light blue with COM port number, indicating successful connection
Note: If the Added message does not appear, then try to re-install USB derivers or change the USB port on the computer.
Step-7: Select these files extracted from I9300XXUGNB4 folder
a) Click the PDA button and select the .tar.md5 file
b) Click the Phone button and select file with MODEM in its name
c) Click the CSC button and select file with CSC in its name
d) Click the PIT button and select the .pit file
Note: Ignore the last three steps (step-b, c and d) if such files do not exist.
Step-8: In Odin enable Auto Reboot and F.Reset Time checkboxes. Click the Re-Partition checkbox if a .pit file has been chosen in the previous step
Step-9: Verify everything and click the Start button in Odin. The installation process should begin now and take about few minutes to complete
Step-10: When the installation process is completed, the phone will restart automatically and soon a PASS message with green background will appear in the extreme left box at the very top of Odin. Disconnect the phone from the computer
I9300XXUGNB4 Android 4.3 latest firmware should now be installed on the Galaxy S3. Navigate to Settings>> About device to verify the new firmware version running on the device.
How to fix bootloop issue
If the Galaxy S3 gets stuck at booting animation (after step-10), go to recovery mode by pressing and holding Volume Up, Home and Power and buttons together. Now perform Wipe data/Factory reset then Wipe Cache Partition. Once the action is completed, reboot the phone by selecting reboot system now. In recovery mode, use Volume keys to scroll between options and Power button to select the desired option. Note that performing wiping task will erase the phone’s internal memory data.
