How to Unroot T-Mobile Galaxy S3 and Restore Back to Stock Firmware



This comprehensive tutorial is designed to help you clear the binary counter, unroot T-Mobile Samsung Galaxy S3 SGH-T999 and revert it back to stock firmware.

Check the binary counter:

  • Turn the Galaxy S3 SGH-T999 off; press and hold the Volume Down, Home and Power buttons together. Press Volume Up then.
  • Check the indicator for the number of counts.
    binary counter galaxy s3 sgh-t999
  • If the counter isn't null and like Yes (1 Counts) or more, reset it first to restore your Samsung Galaxy S3 from custom modifications. In case of no counts, skip the following process of resetting the flash/binary and continue to the steps afterwards.

Reset the flash/binary counter for the Samsung Galaxy S3 T-Mobile SGH-T999:

Required files: get Triangle Away by Chainfire from Play Store, install it and follow this guide to reset the binary counter.

  • Enable WiFi on your Galaxy S3, and launch Triangle Away. It will download some data. When the download is complete, click Reset Flash Counter.
  • SGS3 will now boot into Reset flash counter warning Menu. Press Volume button to start reset flash counter.
  • Your smartphone will reboot once reset flash counter completes.
  • To confirm the process, recheck the counter in Download mode. It should now display 0 counts.

Once we have reset the binary counter of Galaxy S3, proceed to re-installing SGS3 official firmware provided by Samsung for T-Mobile Samsung Galaxy S3 SGH-T999. Re-installing the stock firmware will wipe the root kernel and unroot your Samsung Galaxy S3.

Prerequisites before you unroot T-Mobile Galaxy S3 and restore back to Stock firmware:

  • Ensure that SGS3 is fully charged.
  • This guide will use Odin which does not work on MAC OS. So use a computer running Windows OS.
  • Make sure to close the KIES and stop it even from running in the system tray. KIES interrupts Odin and will block it from flashing.
  • Enable USB debugging in your SGS3 phone: Settings Applications Development, and check the Enable USB debugging box.
  • Perform backup of all your data while using your custom ROM and then perform the wipe data/dalvik cache operation to get rid of any bootloops.
  • Stock ROM packages come in two formats: Full-Wipe (delete the stored data after flashing) & Non-Wipe (doesn't delete phone’s stored data). It is though highly recommended that you should back up all the important files stored in your SGS3's internal memory before flashing regardless of stock ROM package.

Unroot Samsung Galaxy S3 and revert it back to Stock firmware:

Required files: download SGH-T999_GSIII_USB_Driver and Odin3_v3.07. Choose the Stock Firmware for your Galaxy S3: Jelly Bean or Ice Cream Sandwich from these links (4.1.2 Jelly Bean T999UVDMD5, 4.1.1 Jelly Bean T999UVDLJC, 4.1.1 Jelly Bean T999UVDLJA, 4.0.4 ICS T999UVALJ4, 4.0.4 ICS T999UVALH2 and 4.0.4 ICS T999UVALEM).

Extract the file to get the .tar.md5 file and install the USB drivers. Also, install and run the Odin on your computer. 

  • Turn the SGS3 off and reboot it into  Download mode:press and hold the Volume DownHome and the Power buttons simultaneously. You'd be prompted with a warning screen, simply press Volume up to get into download mode.
  • Next, connect the smartphone to your PC using the USB cable. When the device is connected, ID:COM box in Odin will turn blue and an “Added!!” message will be displayed on Odin screen.
  • Click on the PDA button in Odin and locate the stock folder where the .tar or .tar.md5 had been extracted to. Select and load it. Ensure that RE-PARTITION is unchecked whereas AUTO-REBOOT and F.RESET TIME checkboxes are both checked.
  • Once done with settings, hit the START button to begin flashing the stock ROM.
  • It will take a few minutes. When the Stock ROM installation successfully completes, you will see a message saying “PASS” in Odin. Your Galaxy S3 will then automatically reboot. Disconnect the phone from PC.

Ta da! Your Galaxy S3 SGH-T999 is now unrooted and back to its official stock firmware. Verify the stock firmware installation: Settings > About Phone > Firmware info.