How to flash a AT&T Galaxy S9 SM-G960U with a T-Mobile Stock Rom?

Search This thread

jrockz3000

Member
Jul 10, 2016
9
8
Hello,

I've been trying to find my answers on how to flash a AT&T GS9 SM-G960U with a T-Mobile S9 Stock Firmware\ROM.

I found this thread and although it's fairly close to what I am trying to do, I didn't want to post this there because they are talking about flashing U1 to U and I'm not sure if that is what I need to do exactly. https://forum.xda-developers.com/galaxy-s9/how-to/how-to-flash-u1-firmware-to-device-t3765200 from this thread, I've followed the initial steps and although Odin (Moded Odin v3.13.1 Raymonf ) tells me that the flash passed, upon reboot, the phone does not have the TMO firmware, it's still the original AT&T firmware. The only thing that it did do was add the TMO Visual VM icon\app.

I was informed of being able to download the TMO firmware from here: https://www.droiddosh.com/2018/04/samsung-galaxy-s9-sm-g960u-firmware-tmobile-usa-G960USQU1ARBG.html

Am I doing something wrong here? It seems that maybe these US models do not offer the OEM Bootloader unlocker option in developer settings unless you purchase the U1 version direct from Samsung that does not have a locked boot loader? I got this phone at no cost so that is also why I did not purchased from Samsung directly.

Any guidance and help would be appreciated.

Thank you
 
Last edited:

Goronok

Senior Member
Mar 24, 2011
1,020
512
Chicago
US carrier models have locked bootloaders, no way to root or install custom roms.

We should be able to flash between carrier versions/CSCs like we could with the S8, but the process is different and I've only read of a few people finding success in trying. The voicemail app you're seeing is due to flashing the T-Mobile userdata partition. This is the bloat partition - doesn't actually change device features, etc.
 

dovid

Senior Member
Apr 26, 2006
105
26
Any chance anybody has success doing this? It seems like a "Must Have" feature to switch carrier roms on the G960U between carriers, including Boot Screen/Logo, Firmware, Bloatware, etc.

All the goodies.

Any help?

Thank you,
 

jrockz3000

Member
Jul 10, 2016
9
8
I've done it!

Any chance anybody has success doing this? It seems like a "Must Have" feature to switch carrier roms on the G960U between carriers, including Boot Screen/Logo, Firmware, Bloatware, etc.

All the goodies.

Any help?

Thank you,

I've completed this task tonight thanks to some great help from a user that stepped me through it on a TMO Forum.

First an FYI, I first was able to flash my AT&T S9 version from SM-960U to a Stock SM-960U1. It worked great. After that, I was able to flash the TMO Rom and it's also working perfect. I'm not sure if it's required or not to flash the phone to a U1 first or if the TMO Rom can just be flashed. After I flashed the TMO firmware, I had no issues downloading and installing the latest TMO update. (My device is unlocked as well)

It's best to use Samsung switch first to backup your texts, pics, etc. first if you want to restore them to the device after completing the flash. The below instructions will start the phone up as if it was new out if the box.

Here is what I was provided with and the steps I followed.

To Flash the SM-G960U to a SM-G960U1

1. Allow\Enable USB Debugging in Developers settings.

2. Download the U1 Firmware here: https://androidfilehost.com/?w=files&flid=257063
(this is the U1 from Samsung, it's compressed but once extracted it will be around 4GB's of data.)

3. Download the ADB tools: https://devfiles.co/download/PDYvOWBg/platform-tools-latest-windows.zip. Create a folder on your desktop and name it ADB (for easy reference)

4. Download Odin: https://drive.google.com/file/d/10dSyPTuccP8Km9MnDrvbRdS-CAcgFZB3/view

5. From windows, run command prompt, in the command prompt type the following: cd C:\Users\XXX\Desktop\ADB
(XXX is your username)

6. Connect your phone to a USB port on your computer, your phone should prompt you to allow the connection to\from your computer. Allow the connection. Might be best to choose to "Always Allow"

7. Return to the command prompt and type in: adb devices You should see your device listed.

8. In the same command window, type in: adb reboot bootloader This will auto reboot your device into the "Download" mode.

9. Open and run Odin, add the corresponding tar files to the respective area's, in the "options tab" in Odin, make sure that only "Auto Reboot" and "F. Reset Time" is checked.

Click "Start" and the process will take a few minutes to complete.

Allow the device a few minutes to auto reboot and start up.

After you get through all the post boot setup screens, open a phone dial pad and type in, *#2263#. then make sure that all LTE bands are enabled.

Here you can find the SM-G960U T-Mobile Files: https://www.droiddosh.com/2018/04/samsung-galaxy-s9-sm-g960u-firmware-tmobile-usa-G960USQU1ARBG.html
 
Last edited:

dovid

Senior Member
Apr 26, 2006
105
26
Switching from U -> U1 -> U

B"H

Ok, thank you.

1. So stock G960U (Original Carrier) -> Flash to U1 -
2. Then, Go from G960U1 -> Stock G960U (Any Carrier)

Few questions:
1. Which CSC file are you using to flash -- CSC_HOME?
2. In moving from U1 -> U, do you need the final carrier SIM inside the phone?

I've tried this with a Verizon phone I'd like to convert to XFinity (CCT). I flashed the G960U VZW to G960U1 XXA. That worked fine. Then I flashed the G960U CCT rom, and the phone just boots up Verizon. When I check the CSC, it says "VZW/VZW/VZW", even though I flashed the CCT rom.

I don't have an XFinity sim card, so perhap that is the problem.

Any help would be great.
 

ajairola

Senior Member
Jan 1, 2010
71
23
Pearland
B"H

Ok, thank you.

1. So stock G960U (Original Carrier) -> Flash to U1 -
2. Then, Go from G960U1 -> Stock G960U (Any Carrier)

Few questions:
1. Which CSC file are you using to flash -- CSC_HOME?
2. In moving from U1 -> U, do you need the final carrier SIM inside the phone?

I've tried this with a Verizon phone I'd like to convert to XFinity (CCT). I flashed the G960U VZW to G960U1 XXA. That worked fine. Then I flashed the G960U CCT rom, and the phone just boots up Verizon. When I check the CSC, it says "VZW/VZW/VZW", even though I flashed the CCT rom.

I don't have an XFinity sim card, so perhap that is the problem.

Any help would be great.

You most likely will need a Xfinity Sim Card. I was able to convert my Xfinity Mobile S9 to AT&T by going to U1 firmware then inserting my AT&T sim card then flashing the AT&T U firmware.
 
  • Like
Reactions: dovid

B AdamsHxC

New member
Apr 19, 2018
2
1
Question

Does anyone know if you have to have the phone unlocked before changing over carriers? for example if i had a Galaxy S9 from Sprint and wanted to change the firmware to T-Mobile would it work or would it still be locked to Sprint? Thanks for your Help!
 
Last edited:
  • Like
Reactions: PieceofSlice

B AdamsHxC

New member
Apr 19, 2018
2
1
Have the same question, but on my Verizon Note 8...

I would check if your phone is already unlocked, Most Verizon phones come unlocked (unless you bought them from a Verizon Tent at Cosco or stores like that) Just put in another carriers sim card and check, if it is unlocked then you shouldnt have to flash anything, once you put in a different carrier sim it will tell you to restart your phone and once you do it will come up with the new carriers splash logo and apps
 

Xamuyees

New member
Jan 9, 2016
1
0
Noob here: I’ve read that all US S9 models are the same in terms of hardware, is that true? Would that mean if I change the firmware from verizon to T-Mobile, it’ll be fully compatible?
 

ckhalasi

Member
Sep 12, 2012
5
0
For those of you that use TMO or U1 firmware on an unlocked ATT phone on TMO network, do you get a <Subject: NoSubject> before other people's texts in group texts? I've tried flashing U and U1 firmware several times as well as factory reset without being able to get rid of the subject line. Anyone have any insight or suggestions?
 

Littleibrat

New member
Aug 13, 2018
2
0
I was able to go from U1 to the att firmware. My question is why does samsung pass not work? I can see that the knox is not tripped and google play store is certified. Device status says official. Device is not rooted but Samsung pass thinks it is rooted. Why would this happen when all I did was install the carrier bundle?
 

JonnyCHF

New member
Sep 14, 2018
2
0
Odin link down

I've completed this task tonight thanks to some great help from a user that stepped me through it on a TMO Forum.

First an FYI, I first was able to flash my AT&T S9 version from SM-960U to a Stock SM-960U1. It worked great. After that, I was able to flash the TMO Rom and it's also working perfect. I'm not sure if it's required or not to flash the phone to a U1 first or if the TMO Rom can just be flashed. After I flashed the TMO firmware, I had no issues downloading and installing the latest TMO update. (My device is unlocked as well)

It's best to use Samsung switch first to backup your texts, pics, etc. first if you want to restore them to the device after completing the flash. The below instructions will start the phone up as if it was new out if the box.

Here is what I was provided with and the steps I followed.

To Flash the SM-G960U to a SM-G960U1

1. Allow\Enable USB Debugging in Developers settings.

2. Download the U1 Firmware here:
(this is the U1 from Samsung, it's compressed but once extracted it will be around 4GB's of data.)

3. Download the ADB tools: . Create a folder on your desktop and name it ADB (for easy reference)

4. Download Odin:

5. From windows, run command prompt, in the command prompt type the following: cd C:\Users\XXX\Desktop\ADB
(XXX is your username)

6. Connect your phone to a USB port on your computer, your phone should prompt you to allow the connection to\from your computer. Allow the connection. Might be best to choose to "Always Allow"

7. Return to the command prompt and type in: adb devices You should see your device listed.

8. In the same command window, type in: adb reboot bootloader This will auto reboot your device into the "Download" mode.

9. Open and run Odin, add the corresponding tar files to the respective area's, in the "options tab" in Odin, make sure that only "Auto Reboot" and "F. Reset Time" is checked.

Click "Start" and the process will take a few minutes to complete.

Allow the device a few minutes to auto reboot and start up.

After you get through all the post boot setup screens, open a phone dial pad and type in, *#2263#. then make sure that all LTE bands are enabled.

Here you can find the SM-G960U T-Mobile Files:]

Odin link down.
 

Top Liked Posts

  • There are no posts matching your filters.
  • 7
    I've done it!

    Any chance anybody has success doing this? It seems like a "Must Have" feature to switch carrier roms on the G960U between carriers, including Boot Screen/Logo, Firmware, Bloatware, etc.

    All the goodies.

    Any help?

    Thank you,

    I've completed this task tonight thanks to some great help from a user that stepped me through it on a TMO Forum.

    First an FYI, I first was able to flash my AT&T S9 version from SM-960U to a Stock SM-960U1. It worked great. After that, I was able to flash the TMO Rom and it's also working perfect. I'm not sure if it's required or not to flash the phone to a U1 first or if the TMO Rom can just be flashed. After I flashed the TMO firmware, I had no issues downloading and installing the latest TMO update. (My device is unlocked as well)

    It's best to use Samsung switch first to backup your texts, pics, etc. first if you want to restore them to the device after completing the flash. The below instructions will start the phone up as if it was new out if the box.

    Here is what I was provided with and the steps I followed.

    To Flash the SM-G960U to a SM-G960U1

    1. Allow\Enable USB Debugging in Developers settings.

    2. Download the U1 Firmware here: https://androidfilehost.com/?w=files&flid=257063
    (this is the U1 from Samsung, it's compressed but once extracted it will be around 4GB's of data.)

    3. Download the ADB tools: https://devfiles.co/download/PDYvOWBg/platform-tools-latest-windows.zip. Create a folder on your desktop and name it ADB (for easy reference)

    4. Download Odin: https://drive.google.com/file/d/10dSyPTuccP8Km9MnDrvbRdS-CAcgFZB3/view

    5. From windows, run command prompt, in the command prompt type the following: cd C:\Users\XXX\Desktop\ADB
    (XXX is your username)

    6. Connect your phone to a USB port on your computer, your phone should prompt you to allow the connection to\from your computer. Allow the connection. Might be best to choose to "Always Allow"

    7. Return to the command prompt and type in: adb devices You should see your device listed.

    8. In the same command window, type in: adb reboot bootloader This will auto reboot your device into the "Download" mode.

    9. Open and run Odin, add the corresponding tar files to the respective area's, in the "options tab" in Odin, make sure that only "Auto Reboot" and "F. Reset Time" is checked.

    Click "Start" and the process will take a few minutes to complete.

    Allow the device a few minutes to auto reboot and start up.

    After you get through all the post boot setup screens, open a phone dial pad and type in, *#2263#. then make sure that all LTE bands are enabled.

    Here you can find the SM-G960U T-Mobile Files: https://www.droiddosh.com/2018/04/samsung-galaxy-s9-sm-g960u-firmware-tmobile-usa-G960USQU1ARBG.html
    1
    B"H

    Ok, thank you.

    1. So stock G960U (Original Carrier) -> Flash to U1 -
    2. Then, Go from G960U1 -> Stock G960U (Any Carrier)

    Few questions:
    1. Which CSC file are you using to flash -- CSC_HOME?
    2. In moving from U1 -> U, do you need the final carrier SIM inside the phone?

    I've tried this with a Verizon phone I'd like to convert to XFinity (CCT). I flashed the G960U VZW to G960U1 XXA. That worked fine. Then I flashed the G960U CCT rom, and the phone just boots up Verizon. When I check the CSC, it says "VZW/VZW/VZW", even though I flashed the CCT rom.

    I don't have an XFinity sim card, so perhap that is the problem.

    Any help would be great.

    You most likely will need a Xfinity Sim Card. I was able to convert my Xfinity Mobile S9 to AT&T by going to U1 firmware then inserting my AT&T sim card then flashing the AT&T U firmware.
    1
    Question

    Does anyone know if you have to have the phone unlocked before changing over carriers? for example if i had a Galaxy S9 from Sprint and wanted to change the firmware to T-Mobile would it work or would it still be locked to Sprint? Thanks for your Help!
    1
    Can anyone help please ODIN file is not available.

    You can find it here.
    1
    Thanks, I have a question, I am try to flash T-Mobile ROM on xifinity S9 that has android 8 on it. should I proceed with the same process. or get the latest T-Mobile ROM. Please help

    You need to factory wipe and flash to the U1 non-carrier specific firmware first after enabling USB Debugging in the Developer Options once you factory reset. Pop your T-Mobile SIM in and put the device into download mode. Make sure you find the U1 version that has the same or a newer bootloader than your device currently has. You can not flash a previous version of the bootloader. Do not use the file called, HOME_CSC when flashing any of the firmware unless you want the potential for issues. Once you flash the U1, skip through the setup, don't activate WiFi or sign in with your Google account and head straight to enable USB Debugging once again in Developer Options. Back into download mode and flash the TMB firmware, again making sure you don't flash the HOME_CSC (there is another CSC that does need to be flashed) and everything should be good.