Install Android 5.1.1 Lollipop on AT&T Galaxy S5 SM-G900A [G900AUCU4COI5 firmware]


Finally AT&T started rolling out Android 5.1.1 Lollipop via G900AUCU4COI5 firmware for AT&T Galaxy S5 SM-G900A. We have mentioned three update method for your ease including OTA, Kies and Odin, you can follow anyone of them you find easy. The Android 5.1.1 Lollipop G900AUCU4COI5 firmware for AT&T Galaxy S5 SM-G900A brought much improved features including improvement in Ultra Battery saving mode along security patch for Stagefright, so beside upgrading firmware version the G900AUCU4COI5 firmware is also a security update.

Samsung is rolling out firmware updates for most of the awaited devices on daily basis and we have posted guide on the firmware update process of these devices. In the following guide we are going to use the same process to update G900AUCU4COI5 firmware on AT&T Galaxy S5, just go ahead and start the installation procedure below you can find the G900AUCU4COI5 firmware information.


G900AUCU4COI5 firmware details:

Model Name: Samsung Galaxy S5 (AT&T)
Model: SM-G900A
Version: Android 5.1.1 Lollipop

Samsung Galaxy devices can be updated to newer firmware by three different software update methods. You can follow any one of them you find easy but every firmware update process has some limitations and requirements. If you have installed custom recovery on your device it will be replaced by the Stock Recovery image and your device will become completely Stock after flashing the firmware. Below are the three firmware update methods you can follow to update your AT&T Galaxy S5 SM-G900A on Android 5.1.1 Lollipop.

How to update AT&T Galaxy S5 SM-G900A to Android 5.1.1 Lollipop via OTA (Over The Air) method

This is the first and preferably the most easiest method to update your AT&T Galaxy S5 SM-G900A to G900AUCU4COI5 firmware. You can use your device to download the firmware file if available and then the device will ask you to install the updates now or later. As we mentioned above the limitation of OTA method is that you can update your device to latest firmware only as long as you are present inside the region where the OTA has landed and your device is in stock un-rooted condition because rooted device will not able to receive the OTA updates then you have to un-root your device or switch to the alternative methods like Kies or Odin. To check whether your device is eligible for OTA Firmware update, unlock your device & navigate to

Settings >> About device >> Software update >> Check for updates

This will require a working internet connection to connect to the Samsung servers. You will receive a notification about the latest firmware availability click install to flash the firmware or tap install later to flash the latest update anytime later.

How to update AT&T Galaxy S5 SM-G900A on Android 5.1.1 Lollipop via Samsung Kies

Samsung Kies is another useful firmware update application for Samsung and a bit easier to use, just follow the below steps to update your AT&T Galaxy S5 SM-G900A to G900AUCU4COI5 firmware using Samsung Kies.

  • Download the Samsung Kies application from the Samsung website and install it on your windows PC or Mac.
  • Once the installation process completes, click the Kies icon to run the application.
  • Now connect your device to the PC using USB data cable.
  • You device will be automatically detected by Kies application and now you can perform multiple functions apart from the firmware update. The Kies application allows you to create a backup of your device before updating to new firmware, click the “Backup and Restore” button and follow the on screen instructions.
  • Once you successfully created a back up of your device now you can update your device to latest available firmware.
  • Click the Firmware Upgrade button to check whether new firmware is available for your device, if the firmware is available for your device you will be notified.
  • Proceed further and follow onscreen instructions to start the Update process.
  • Your device will reboot automatically once the process is completed.

If this process doesn’t helped you, proceed further to manually update your AT&T Galaxy S5 SM-G900A to latest firmware via Odin. Odin is a third party tool use to update the device firmware, this is a manual way to update the device firmware if the above two methods doesn’t work for you.

How to update Android 5.1.1 Lollipop on AT&T Galaxy S5 SM-G900A manually using Odin

To update your AT&T Galaxy S5 SM-G900A via Odin tools you need to download necessary files which you are going to use in the update process.


Download and Extract Odin 3.10.6

Download Samsung USB drivers

Before you Begin:

Disclaimer: This tutorial includes multiple operations which include flashing Stock Firmware, Custom ROM, Custom recovery and rooting. Follow the guide on your own risk, we are not responsible if you brick or damage your device however the chances of bricking a device are rare but you have to pay full attention on the complete guide to avoid any issues and difficulties while performing any of the above mentioned operation.

Please ensure your phone battery should be charged at minimum 60%

Enable USB Debugging, go to Settings >> Developer Options >> USB debugging

Note: If you can’t see Developer Options on your device setting’s menu then you have to perform an extra step, go to Settings >> About device >> Navigate downward till you see an option “Build number” Tap it seven time quickly until it says “you are now a developer” . This will enable Developers Options on your device in the Settings menu now go back and enable USB debugging as described in the above step.

Download and Extract G900AUCU4COI5 firmware file from the below provided link.

Download G900AUCU4COI5 for Galaxy S5 G900A but you need to be on OF3 firmware to install it, if you are on the OF3 firmware then you need to flash the COI5 firmware file via stock recovery.

Odin flashable file will be available soon try the above one.

Process to update AT&T Galaxy S5 SM-G900A to G900AUCU4COI5 firmware

If you are new to this tool then you have to pay attention on the step by step sequence to avoid any mishap during the update process.

  • Click Odin.exe to run the Odin tool.
  • Now boot your device into Download Mode by turning off your device properly and turn it on again by pressing and holding Home Button+Volume Down +Power Key simultaneously until you see a warning now press Volume up to enter Download Mode.
  • Connect your device to PC via USB cable.
  • If you have properly installed USB drivers on your PC, Odin will detect your device and the ID:COM box should turn blue which indicates that your device has been successfully added.


  • Please make sure “Auto Reboot & F.Reset Time” options are checked in the Options Tab on Odin screen.
  • Now click the AP tab and select the firmware TAR file that you have downloaded and extracted earlier.
  • Hit the start button at the bottom and wait for the installation process to complete.


  • Once the firmware update process is completed you will see a “PASS” message in the ID:COM box (as shown).
  • Your device will automatically reboot with the newly flashed firmware.

What to do if your device stuck in boot animation

This is an optional method if your device is taking longer and won’t boot and stuck on the Samsung logo for the duration of more then 10-15 minutes. This is bootloop or soft brick, you can perform the below described 2 steps to fix the bootloop. However the chances of getting sofbrick are rare after flashing Stock Firmware.

  • Pull the battery out from your device and re-install it.
  • Now boot your device into stock recovery mode by pressing and holding the volume up+Home+power buttons simultaneously.
  • Once your device boot into recovery mode, from the main menu select Wipe Data/Factory Reset and Wipe
  • Cache Partition then go back and select reboot system now. (Use volume keys to navigate)

That’s it! You have successfully updated your AT&T Galaxy S5 SM-G900A to G900AUCU4COI5 firmware. If you have any query feel free to contact us by posting your queries in the below provided comment section. Follow us on Facebook/Twitter/Google+ for future update.

A Software Engineer who loves to hang around latest gadgets and writes his own experiences to get the best possible and accurate information.

  1. Reply
    Dani October 24, 2015 at 3:04 pm

    You will be active when the link to download the firmware

  2. Reply
    Hamid October 26, 2015 at 4:08 am

    Sweet! I’ll keep checking back to this page to look for the download for firmware so I can update it with Odin

  3. Reply
    George November 23, 2015 at 11:34 am

    As of now I’m overseas and cannot get the update. Any progress on this link to download the firmware to upgrade via Odin?

  4. Reply
    Rzgar January 17, 2016 at 1:29 pm

    when this version 5.1.1 for G900A will be uploaded? because my phone is in a condition that cant be turned on it just shows the SAMSUNG logo…. plz reply asap.

    • Reply
      Alee January 17, 2016 at 4:07 pm

      we ll upload it as soon as it become available, but you need to flash the older version of G900A firmware for your device, it’s nothing to worry about your device is softbrick, just reflash the firmware and you will be all set

  5. Reply
    Abbey February 14, 2016 at 6:46 pm

    Any time I check for update it always tell me to check back after 23hours what can I do to get the update please guys?

  6. Reply
    JD March 21, 2016 at 2:21 pm

    Any updates on the link to the firmware?

    • Reply
      Alee March 22, 2016 at 8:21 pm

      We will update the link as soon as we find it

  7. Reply
    baze March 24, 2016 at 6:58 pm

    cant download,page not found?

    • Reply
      Alee March 26, 2016 at 5:34 am

      Thank you for letting us know, Link has been updated now

  8. Reply
    Peruvian March 27, 2016 at 12:28 am

    When the gm900a file be available?

  9. Reply
    Eric March 29, 2016 at 2:18 pm

    So I need to currently have OF3 on my phone to upgrade to OI5 via Odin? If so, is there a OF3 file that I can use to do the Odin steps, before continuing?

  10. Reply
    smeas April 15, 2016 at 9:49 am

    i have sm-g900A G900AUCU2ANG3 firmware ..can i use this methode for updating my phone ?

  11. Reply
    alan April 26, 2016 at 11:08 am

    how do i install the non odin file? is there an odin file available? i see no link

    • Reply
      Adney April 28, 2016 at 5:46 am

      it is mentioned in the link sir please check it carefully

  12. Reply
    Tara May 3, 2016 at 12:41 am

    Hi, I got to the part where i need to click AP in Odin to find the firmware file. I have downloaded the firmware file with the link that was provided in this article, but it doesn’t show up for me to open it with Odin. Did I do something wrong?

    • Reply
      Adney May 3, 2016 at 5:11 pm

      you should provide the correct path where you have placed the firmware file

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