Galaxy S21 SM-G991B U4 Firmware – Android 12

G991BXXU4BULF

The specific Galaxy S21 SM-G991B U4 Firmware Download Package comes with a Stock ROM of Galaxy S21 SM-G991B U4 Security Patch Level 2022-02-01 (February 1, 2022). This helps you to bypass the FRP lock and revert from the root and custom ROM.

Samsung Galaxy S21 SM-G991B Binary 4 Android 12 Brazil ZTO G991BXXU4CVB8

There are various reasons to flash “Stock Firmware on Galaxy S21 SM-G991B U4“. For instance, if your phone gets stuck on the logo and you need to remove the FRP lock from it.

If you’re going to reset your phone hard and cannot access the recovery menu. But most of the problems that cause flashing stock ROM are below.

The Advantages Of Stock ROM:

  • Fix boot loop issue
  • Update and Downgrade
  • Unroot or Fix Bugs
  • To solve the lag or stutter
  • Fix software issues.
  • Revert to stock firmware

Pre-requirements:

Galaxy S21 SM-G991B U4 Stock ROM Details:

SM-G991B U4 Brazil ZTO G991BXXU4CVB8:

Model SM-G991B Binary 4 U4, S4, Bit 4
Region / Country Brazil
Language Multi-Language
Android version Android 12 S
Operator / Carrier Clean ZTO (no logo, carrier apps)
AP / PDA G991BXXU4CVB8
CSC G991BOWO4CVB8
MODEM CP Version G991BXXU4CVB8
product code ZTO
Build Date 2022-02-16
Security Patch Level 2022-02-01 (February 1, 2022)
Size 6.6 GB
[quads id=2]
Download Google Drive Android File Host
SM-G991B U4 Brazil ZTO G991BXXU4BULF:
Model SM-G991B Binary 4 U4, S4, Bit 4
Region / Country Brazil
Language Multi-Language
Android version Android 12 S
Operator / Carrier Clean ZTO (no logo, carrier apps)
PDA G991BXXU4BULF
CSC G991BOWO4BULG
MODEM CP Version G991BXXU4BULG
product code ZTO
Build Date 2021-12-23
Security Patch Level 2022-01-01 (January 1, 2022)
Size 6.4 GB
Download Google Drive Android File Host

How To Install Galaxy S21 SM-G991B U4 Stock Firmware:

1: Download and Install Samsung USB Driver on your computer. If a Samsung USB Driver is already installed on your computer, then Skip this Step.

2: Download and extract the Galaxy S21 SM-G991B U4 Firmware files on your computer.

3: Now, Switch off your Smartphone.

4: Turn off the phone and boot into Download Mode.

Press and hold Volume Down, Home and Power button at the same time for 5-8 seconds until download mode is active.

5: In Download mode a Warning Yellow Triangle Sign appeares . Press Volume Up to proceed.

6: Open Odin. Then, connect your phone to the pc.

7: Once you have connected the Smartphone to the computer, Odin will automatically recognize the device and show the “Added” message on the lower-left panel.

8: Click the PDA button and select the Firmware.tar file.

9: Now, click the Start button in Odin to begin the Flashing.

10: Flashing usually takes 30-50 seconds to complete the process on your Phone.

Once you spot the “Pass” message in Odin, you can unplug your device from the computer.

When your Galaxy S21 SM-G991B U4 finally boots up, you should now be running your desired firmware.

To verify the installed firmware, go to Settings → About Phone → Software Information. Check the firmware number under Baseband version.

Disclaimer:

  • Read and understand the Full Guide before flashing.”Galaxy S21 SM-G991B U4 Firmware.
  • Use these instructions at your own risk. We will not be responsible for everything that happens to your device resulting from using information in this guide.
  • Phone must have a 70–80% charge.