Samsung Galaxy S5 (AT&T) SM-G900A Firmware Overview
What is the latest SM-G900A firmware?
G900AUCS4DQD1, released May 8, 2017 . It is a security update on bootloader binary 4. The archive holds 3 official builds across 1 region (CSC). Each one is the full stock ROM (flash file) for Odin, not an OTA patch.
Is the Samsung Galaxy S5 (AT&T) still getting updates?
Most likely not: there has been no new firmware since May 2017, so Android 4.4.2 is the last version this model got. The final builds below are still the best choice for a clean reinstall.
Can I downgrade the SM-G900A firmware?
Only to builds with the same bootloader binary (the Bit column) or higher. In the archive the binary of this model rose from 1 to 4:
- Binary 4 — since Mar 2017
- Binary 1 — since Mar 2014
A phone already on binary 4 rejects builds with a lower binary in Odin ("SW REV CHECK FAIL"), so it can go back to an earlier Android version only if that version has a binary 4 build. How to read a build number.
All SM-G900A firmware builds
How to Flash SM-G900A Firmware
Put the Samsung Galaxy S5 (AT&T) into Download Mode, load the BL, AP, CP and CSC files into Odin on a Windows PC and press Start. Pick a build with Bit 4 or higher if your phone is already on the latest firmware. Use HOME_CSC to keep your data, CSC for a full wipe.