[Guide] Service Mode and CSC Guide/Enable LTE/5G Bands and Services/5G Low Band on U1

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Romeo Nickolas

Senior Member
Jun 16, 2022
98
26
Mine is S22 S901U1, but instructions are same
I have done set lte band config but doesnt work

Check if the ca combo doesn't exist.
If not you successfuly removed it. If there's still no CA (LTE+) maybe there's no available CA in your location or you're far from the cellsites.
 

esemyuron

Member
Aug 7, 2016
47
7
26
Yerevan
I have done all, but still dont work
I have an S20 for my region certified, in s20 all aggregation work
View attachment 5729151
Check if the ca combo doesn't exist.
If not you successfuly removed it. If there's still no CA (LTE+) maybe there's no available CA in your location or you're far from the cellsites.
Screenshot_20221007-111257_Service mode RIL.jpg
Screenshot_20221007-111151_Service mode RIL.jpg
Screenshot_20221007-111125_Service mode RIL.jpg
 

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Romeo Nickolas

Senior Member
Jun 16, 2022
98
26
I have done all, but still dont work
I have an S20 for my region certified, in s20 all aggregation work

View attachment 5729161View attachment 5729163View attachment 5729165
Here's what I noticed on XAA they prioritize TDD bands than CA like mine.

In my place band 3 and 28 are aggregated but my phone connects to TDD band 41 most of the time.

And I don't mind this since it's faster in the morning and night but CA on early morning (1AM) is faster.

Try this check what band you're connected now using *#0011#
Mine is band 41
Screenshot_20221007_152312.jpg


Then disable the band on the Band Selection menu. Then check your data indicator if it becomes 4G+ or LTE+.
Screenshot_20221007_152938.jpg

Screenshot_20221007_152844.jpg


Do it again on the band currently connected if still not on CA.
 

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esemyuron

Member
Aug 7, 2016
47
7
26
Yerevan
Here's what I noticed on XAA they prioritize TDD bands than CA like mine.

In my place band 3 and 28 are aggregated but my phone connects to TDD band 41 most of the time.

And I don't mind this since it's faster in the morning and night but CA on early morning (1AM) is faster.

Try this check what band you're connected now using *#0011#
Mine is band 41
View attachment 5729177

Then disable the band on the Band Selection menu. Then check your data indicator if it becomes 4G+ or LTE+.
View attachment 5729179
View attachment 5729181

Do it again on the band currently connected if still not on CA.
I enabled only 3, 7, and 20 bands which is needed, but aggregation not work they work separate
 

intheb0x

Senior Member
Dec 8, 2007
1,492
365
Milwaukee WI
OnePlus 8
I have done all, but still dont work
I have an S20 for my region certified, in s20 all aggregation work

View attachment 5729161View attachment 5729163View attachment 5729165
Check out this thread for info on s22 and also most works for the s20 and .note as.well!

 

intheb0x

Senior Member
Dec 8, 2007
1,492
365
Milwaukee WI
OnePlus 8
Screenshot_20221013-152752.jpg

Can confirm this works on s20 ultra but doesn't unlock n25 but unlocks n41SA (which TMO has blocked )and unlocked all other carriers 5g bands together but no n25. Still working on that.
 

Romeo Nickolas

Senior Member
Jun 16, 2022
98
26
What update is that? Beta?
I found something new as well!, To enable more bands on different carriers!
Nope it's the september security patch
I think I posted on the wrong thread this should be on the note 20 ultra section. Sorry.

Btw the thread you provided doesn't unlock any other bands like n78 on U1 note 20 ultra since removing SA permit list and setting lte band config do this results too.

Screenshot_20221014-050540_Service mode RIL.jpg


It doesn't affect the NR combination too.
I need the b3+n41 combo but the firmware only supports b41+n41.
Screenshot_20221014_051416.jpg
 
Last edited:

intheb0x

Senior Member
Dec 8, 2007
1,492
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Milwaukee WI
OnePlus 8
If someone planning to downgrade just to get the band you want to activate on Samsung Note 20 Ultra 5G US unlocked SM-N986U1

Here's the result:

Before:
View attachment 5689519

After:
View attachment 5689515
View attachment 5689517

It only unlocks band n2 n12 n25 n66 and all available bands in SA.
How did you downgrade and what did you downgrade to in order to get the extra 5G bands? I was reading back and I found this post if you can enable n25 then I should be able to enable n25 on my ultra as well but I'm afraid I'm already on Android 12 so I bet the downgrade to Android 11 probably won't be possible.

I have also heard there was a beta for Android 11 that was released that did indeed unlock most of the 5G bands and they quickly remedied it with a fix but I'm sure the beta is still rolling around out there somewhere or available.
 

intheb0x

Senior Member
Dec 8, 2007
1,492
365
Milwaukee WI
OnePlus 8
Nope it's the september security patch
I think I posted on the wrong thread this should be on the note 20 ultra section. Sorry.

Btw the thread you provided doesn't unlock any other bands like n78 on U1 note 20 ultra since removing SA permit list and setting lte band config do this results too.

View attachment 5733903

It doesn't affect the NR combination too.
I need the b3+n41 combo but the firmware only supports b41+n41.
View attachment 5733905
The thread that I posted with the IMEI simulation tactic or option only unlocks the bands that are FCC verified for your phone so basically if you go ahead and do that and change that to GCF you will open up all 5G bands that are supposed to be enabled for your device not anything more not anything extra so when I'm on the T-Mobile SIM and the T-Mobile CSC I only get the T-Mobile bands available but when I go to GCF it unlocks all the 5G bands for every carrier that this phone is enabled for and since it's a US version it's the 256671-41 and so on but I seen in the earlier post that you were able to unlock in 25 and such and 25 will help me because I know T-Mobile is using n25 for their Network.
 
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Romeo Nickolas

Senior Member
Jun 16, 2022
98
26
How did you downgrade and what did you downgrade to in order to get the extra 5G bands? I was reading back and I found this post if you can enable n25 then I should be able to enable n25 on my ultra as well but I'm afraid I'm already on Android 12 so I bet the downgrade to Android 11 probably won't be possible.

I have also heard there was a beta for Android 11 that was released that did indeed unlock most of the 5G bands and they quickly remedied it with a fix but I'm sure the beta is still rolling around out there somewhere or available.
I just warned users since there's a fix by downgrading when you messed up something on nv files. (Efs explorer)
(SM-N986U1)

Downgrading also is the only way to access the service menu before the other trick has been discovered (samfw tool).

If the android 11 beta to unlock other bands is real then they should never update the firmware with bootloader 3.

On my end I don't need to unlock other bands since n41 is the only available 5G band on my location and it is already available on my device.
The ENDC combination is my only problem that is encoded on the firmware and can't be modified.
I'm looking forward for the android 13 oneui5 if some miracle will happen lol.
 
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intheb0x

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Dec 8, 2007
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Milwaukee WI
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I would benefit from n25 for sure for fireproofing. It's a future T-Mobile band. Along with n77 but I doubt there's anyway possible I'll be able to enable that.but if we had the s21 or newer it would be enabled

As for downgrading,I'm stuck because I'm on 3 as it is. But maybe as time goes by someone will come out with a way to downgrade safely,etc maybe even bootloader unlock etc but whatever.

Honestly I'm curious about something else too. Now on the newest update if I hit "unlock all bands" in the service menu then none of the other bands show up like they used too. Even tho they didn't stick, n1 n2,etc all those would show up even tho they weren't going to stick..now with the newest update no extra bands show up only the ones unlocked normally n2,n5,n66,n41,n71.

What I am curious about though, is when you would enable all bands and you would apply the update you would see the hex codes at the bottom showing what they would be if all the bands were selected but once you hit apply or leave the page you know it would go back to the normal 5G bands that are there.
The extras would disappear and the hex values would change to the stock values in the device I got the values for this, and when you go back to the main screen you'll see the hex values stayed the same from the normal bands that you always have but I copied down all the hex values from when you enable all bands and I'm wondering if there would be some way to write those hex values in a NV editor and do it that way to enable bands or if they would get overwrote on boot or something probably that's what would happen.

But it's something for me to test.

My main goal is honestly a phone with mm wave and c band available what I call Best of both worlds right now I got a phone with mm wave and everything else but I don't have anything available with c-band but one device but it's currently broken right now and it doesn't have mm wave on it and in my area Verizon has a lot of mm wave downtown which I would like to utilize and supposedly they have a lot of sea band in this area too but I'm not able to test.
 

intheb0x

Senior Member
Dec 8, 2007
1,492
365
Milwaukee WI
OnePlus 8
I just warned users since there's a fix by downgrading when you messed up something on nv files. (Efs explorer)
(SM-N986U1)

Downgrading also is the only way to access the service menu before the other trick has been discovered (samfw tool).

If the android 11 beta to unlock other bands is real then they should never update the firmware with bootloader 3.

On my end I don't need to unlock other bands since n41 is the only available 5G band on my location and it is already available on my device.
The ENDC combination is my only problem that is encoded on the firmware and can't be modified.
I'm looking forward for the android 13 oneui5 if some miracle will happen lol.
I'm also trying to update to the 13:beta as we speak but I'm having trouble finding the file for the s20 ultra
 

JeffATL

Senior Member
Oct 10, 2009
853
78
I am still using a carrier unbranded / unlocked N20U. Before dual sim was available across carriers, it was only available on TMO, so using hacked Odin, I flashed the TMO rom and got dual sim to work. I never flashed back. So if using Verizon/Visible sim with TMO rom, does this mean some of my bands are disabled that I need, or it should not affect anything? (having trouble following this thread and getting access to service menu)
 

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    Hello All,

    Many people have asked about service mode and CSC related questions and I thought we should get a discussion going that is all in one place.

    *DISCLAIMER* I do not take any responsibility for any issues that may occur from changing settings in these screens. They have the potential to cause service or data lost if used incorrectly. You have been warned!

    Service Mode Guide

    Access Service Mode

    To access service mode screen, first download the Google Phone App from the Play Store (Phone by Google-Caller ID & Spam Protection is the official Play Store Name)

    After installing the phone app, open it up and select set as default *Note* You will only need the Google phone app to access service mode-Once all the changes are made you can keep using it or change back to what you were using*

    Another pop-up will show and select the Phone (blue icon) and set as default. Go to the dial pad icon in the bottom right corner and dial the following:

    *#*#27663368378#*#*
    When you dial the last * in the string above, the service mode menu will automatically show. YOU SHOULD NOT HAVE TO HIT THE CALL ICON BUTTON TO MAKE A CALL AT ANY POINT.
    GEtmxR5J-vLwrxtogkVOn01je_6Lch2EYPQxJyU6IiCNwyTJFpjO2A4dRkFo68KPtD0zfV4O4_gAj-QXbWbmLbmsIEeHn8nNRhvEM-v6SJXhS2X1x4lPFZD1-Xsvrf2th1nmMxwaXVBwtJ5n6yOBzlJRGvwIC1ev-Ty0VXTcTyy00OuTUaBzLs-7TJEqNFUh-M117UN9q0Pu3i3csDxjRdNV0fN3zw4eT2WRogZcG3JrrimHnUZEPa9seBdvU9NOarASEZYWEWIMc1-ko9vaXlnNjJUuhPiNnSxXOwPyKK_pLdar0OSzOXgwsaWFPm3sJ-qLZjQc3EP-NDqg_n2qyUCaeamVnPf16_Rxjxwmu1GRSYLOzqwBlg0GjpncgqdeDPXP-Dn2QcHlSgmaATEH_vArZOsdMY8PW8MmbVA4IpwmhFy2pGqb-iNIh6SLlWlHDEpGqrHCZhWMMeF9Nq83-4H6uo3QDAdXuyHkEYB7c7Cu6_DmzsmUUClbq5XgqDzsYrRj23ed6d1pV0_yUvqTCWkWKpqaw2TpJjlafdfbXCrOdKUxSBW-tZ-JLjOgFPpqcRRj11-jgMNy9Rg5NcWJsXV2NGbeMFQQAFa4Rsty2E2q5z1JpQiRXbrzn5lWlGwKAkYBb8IlwRBCEzVmjJIay_VOLDvbYYrGHaqyT5JRssv-SDjPxOqhIYVQA82Z=w373-h800-no
    .

    Congrats, you are now in the service mode menu!

    Enable all LTE and 5G Bands
    *NOTE* Remember whenever navigating through the menus that the android back button on your device will automatically exit you back to the dialer. To go back, you must use the 3 dots menu at the top and select Back.

    To enable all the LTE Bands go to:
    1-Option 2-UE Setting and Info
    2-Option 1-Setting
    3-Option 2-System
    4-Option 9-Next Page
    5-Option 9-Next Page
    6-Option 9-Next Page
    7-Option 9-Next Page
    8-Option 1-Set LTE Band Config
    9-Option 1-Set Default LTE Band

    This should enable all the LTE Bands for the country that the firmware installed is from and the available roaming bands that are set in the firmware.

    For the 5G Bands go back (using the 3 dots in the top) until you see UE setting menu and the 2 options for Protocol and System then:
    1-Option 1-Protocol
    2-Option 9-NR5G
    4-Option 3-NR5G Prune Status
    Here you will see a [1] Remove NR5G PRUNE option as the last line. Select that option. If you visit this menu later, it will show a * next to NR5G PRUNE is Removed and the option will change to [1] Restore NR5G PRUNE, in case you want to go back.

    Enable DSS

    Now that all the bands are enabled, you have to enable the DSS setting. Get back to UE SETTING MENU with Protocol and System options and:
    1-Option 1-Protocol
    2-Option 1-AS
    3-Option 9-Next Page
    4-Option 9-Next Page
    5-Option 2-NR DSS CONTROL
    6-Option 1-NR DSS ENABLE

    Just reboot the phone after this and this should be all that is needed to enable all LTE and 5G Bands and DSS!

    You can then go back into the Google dialer and dial *#*#2263#*#* and this screen will pop:
    g23W28hUIrJQHoFhP371hn1XQCK_w3b9JCOxfOL-bbhSB59PcquenA81d6n-O0HVtLbWbl3jMOgOSacBvtO5bFkpgzjIwMuRpeWntB8tt6xbOajvVxGILaaS_lrhvwlwC6EFC9sBZJsCqKIWTV4ZzEe27mVC6N87ghDJdTI6Ho6SdACNub_PC2Cey1EN8c6wdp96yckcA-C2b7MGZnrplsXHmslJOs0HDU1CO8uxdggQ6xKS5y4SVp0Xz80qsEpVhpakBC173cWSxPsuKS0LUQNgmvVcsA4NakqDSMaeI3luoI_2cpOn52B6k0TCZQOROYdDrT51mb1PXmP3Rk0V1F_lvqn-Yw6t0qrxXHoF1mDjw0fAeFRtQsS2SwbrV5Cbmuc-S5XGbWtiBQ9eTp6c3eXN7y2VtQHTgAcVyd54q0TZXALpPYb9l6vEkqBOejVbuAaGqAQFwRjJY-XEoQss1n_zNcQIVYLq8XSK9s80AlNB8ZG7zXJJk1EdnEcDpe9w--idATqW8AjC8-ZEtevgfvrAdaiZsEgbKSjQ3cQOS9rOsekqG3grAl0jb5jkHTcNw4BoIV4rDG2QYV-2bAH1-tpiwcNXN63izIYcykfMnvMHa9oqr68eN77G96WjMG6U7VcnQMsz26J-55MbHYshBSdkIua8Nk14tqhTyXLc1KmgyNzomCw05REvmmJB=w373-h800-no


    CSC Guide
    CSC (which I think means Carrier Service Code) helps to set what options for settings show in the device for things like voicemail and wifi calling, as well as sets network code information for things like carrier aggregation combos.

    When you go to your phone settings->about phone->software information and look in the Service Provider SW ver. section, you will see as the last line a combo like XXX/YYY/ZZZ. This indicates what carrier sales and network code is set and what brand the phone was manufactured as.

    I think of the XXX/YYY/ZZZ configuration as follows
    XXX=Sales Code-What kind of features are setup in the firmware like wifi calling, video calling and settings menus
    YYY=Network Code-What kind of network features are set for things like carrier aggregation and LTE/5G bands
    ZZZ=Manufactured as Code- What model the phone was originally manufactured as. Ot has no affect on the system settings or options. THIS CAN NOT CHANGE. IT SHOULD ALWAYS BE THE SAME. ONLY A ROOTED PHONE WOULD BE ABLE TO ACCESS THE FILES NECCESSARY TO CHANGE THIS.

    For the Example of VZW/VZW/XAA, this would mean that the phone was sold as unlocked from Samsung and has a VZW SIM in it, setting the sales and network codes to VZW (XXX and YYY should usually be the same since you want the Network setup to match the settings setup in the phone, but they can be different, especially if you try to change the CSC in the U carrier branded firmware.)

    Changing CSC
    *NOTE*Changing the CSC does not necessarily need the Google phone dialer like for the service menu, however, if you are on a CSC where the stock dialer does not provide you with the CSC change screen (Like when your code is XAA/XAA/XAA) you can attempt it through there and see if you can access it. I haven't been able to test this yet, so let me know.

    First, go to settings->about phone and at the top you will see your IMEI. Press and hold on the IMEI number and you will get a popup saying copied to clipboard. Then, go to the phone dialer and dial:
    *#272*
    After you see the numbers dialed at the top, press and hold after the last * and select paste then dial #. Again, you should never have to actually press the call button. A screen will auto pop. If it does not, try the Google dialer.
    Zhs2G-GcSTO6ksWLj_4WmQeqBzyN1NBQPM2whbwJKbygN0WbeqJkR_cTZvCQ_wrHknIDwVrp8MI6vIYVwiVCpnT4xr6R48JXd4UtCe1M5eV67eQDZF7kBoY_smYhUYLocbxuu-WQaePyZJW4nL7VCKNJ0ONjFpgffGNpgK2PCoRpccgSGcJ7BMGuYXBR3YqzjzPGD-p8JzEnYPWcILpFYXBvUopsedGhUQsvmrj_HYGGP9J8C3gc_zU3xLw48aQoAtne2c0vfkQf9tDG2I5UsyA4tU0MAsAdnDEEoIBjthW0W86UQ57mWA17NCxjZU0zOZ1I8_wdbz5YjGwAVWkA7Ungko9BSFOllcKxjvIG9N9lKjFm6zOtEjpdvGNReP7WpL0tL_C3x6Tgc_Qs5VLTGpr7ZKYld5q6_i13XsLI6V9ctUH8d7nDXrvPIuhvBWaerBb6tabxb_OnOli_El3LHcsUq-iVfGDP9zxWEHkft_BDxvG6zkv5BaZAR-g55tAur-HHUuReJ_vLt9nXLO7pNMVLzAkF4FkvjgW2hgqowXCvunCMuGl_90hZlWCGLVnXQH9B7p5eaMfrJwVjDdwXy6whiIukizfW7PDltFxqVF0imAD4eFDNm-HAxOAeVz_b1lmMHOftRL9ze_hHu0eE-v9ea0V0xCqIVPfskOyve7KSt5tKa5UyktPWZGHw=w373-h800-no


    *Pro Tip*
    Since some CSCs do not allow dialing the IMEI (like the XAA CSC) I recommend after you get to this screen to first select the recent menus button on your phone and click on the CSC app icon in the mini view. But beware, this is not working in the One UI 3 beta!!
    WWLUpYTaf2havLIVpFl1sPgVx929cLvK62tGuLVVCBcM0h0cc46EFX_ox5y3EsQsasf4GqsnunYuec_nG9iO3YvxLXeSxBp_n_YnL67Hk6gteXwqBWXD3-xWydtcbOz_jS5YzSnTUhnUGAsRBZzT_QxKZWe3jih3Mqlib7-5LwWLAMSOinOqexDsN_Kl9vwyHP8ZK2JGz9FKp7oAXuenDijy2yfqairzVNApqlsX4JU-kMFoEYHkdNDQvLSHjT1je230mRn5BCCKhN_RAQgbu6_bSgHRY16BfdqudV6GJUrJ5RqRL1g4y_63cxB3x3l55QioPFPGnI16ZhQgxGjLqeHSa1wLMP6p6pCiwX7UoBS9r9ytJp05Wi7_Y2PB7b4vHVWRvxVlftIjwA0KdNTGjS__EErLytBK3WKlC3mI3qUq84LMCT5LIGfZL4NtHJYXgg0MrBAgM5E8rc7-2XIXMQcHw97WXALbu6SF1PGKf2ZdJcRVOrRwZbYCEud9R6iyVSJPLh2HFjjqbLOfBMouN5cJ78FjN9WKJtmOjpMkffKxHUuCID5DQiYz8liSBG1mTnu-fQXQBmld-cxuk2ABqUcf6FKNizuKexyjMA_BlmqTmmCXpJhM7qfLCjxMR0QloD55dxfJX18svhl4J9LiTKHPr6K-kovflgnLT-ws1-hHTwad2pJIqqXvFRgF=w373-h800-no


    Then click on Keep Open for Quick Launching
    XkA07c7Yvt-V5nI-DQmWsNwsYQCJNkpe2QkfoUsWTbKv-x-0CXiX7JCC5zRaX5thnP1Xwz1o2VCmn-PEC1sWu7tdUDox7vXQKAMdjWiR448ESqm8Fy4YUK7awTJWMUTitPMuuv0UM9ZApsHDWoKWT5y4NibjijnosXbwSdqu3LrDWD6bkEFNklk2tKIr4G03JXKtS-rLMz7av79fh-Z5BDJnjDwJr06bRcN9znjUGsjhHI8KU47yljIcRIkY2Y_MxnJHAtG-vvQmPxRQmrRvIJiD7kkHqOA6T7TGb3dRiJZAqPo8BFqjAl_939foy3P6oFrZsdhWueO7M-oh3BUCDis4iao7-IjlUdg2wiQS8vfEtOTeFdlNKrX7njgiv3hhoQNzsP-E8PHJAD-qNiuhgJxq557KtfASYQodGMvUXGqzNLI9pBqw6NZypF0nQYcQRjY4lB_gfREmd4yHreWMJhrMcUe392Tj0sC6AFowhpKMU4hvK9Pc1nihTbYsFd5dVAA_TT4CcXvOIwsXl6W45MuGiESv1uv0sMv26zJz9GfuSlQdO4BZj2mjTgnzsd1IyMTX5yeOMKvwinhEyq4hPsA-Lyu72cCMwfdduCBbck6VV_78eJB_w37MXmC2EwkJClRgx4e32jerCioSzvX20ePR0OrP25aGr_k9I-qMvxaQIPT10ef_4GFhizva=w373-h800-no


    Then you will have a lock at the bottom of that apps recent screen to show it will stay in recent menu, even after reboot and selecting close all apps button
    UfrVLrRCcoUCsZ9ioSBTg0QijNg8zrAqlxHIJ3uZDGQKR6CYNTyofN16j9MChBv_m0lTYd6HYGwVMAkAQcYED0nKC-I6gYivb-prgBlu5qCQn8nJ_Es8i2FtW3uJwE-2ltIiFtfR0Ky1t2Z0dGIcDRGnDfwU-M5VTFwh5rS8n83axjMbDKbNIp89H3RzTuRLzfy7RrlpocLKDCODYLPPGu7kMhUTuYJLExMmWR1LFg16rmfeQfCt4LFUj4uZRo6GncaBIAN8MCJp_hoEAPfLIMElxYzp2GWGZO6fGZF0-qeksu75qTiEJss5YpzFCV0SVsiEAV3f_fR7FiMk6L2p90-dn_mDiO4U8K4lfgP8kFnLeQqLjJoSHxV4wT7VhcHF7IFnxm1QKL8sjHzgcZO_MYGQGWXi5c9TJaFG4HI6tMMMe-IItjz_GR5VQyoTxO4N5kpVAAYqn2E1pRXpD5dBoFqqjGOwXQ8QcprEPZMZJZ8xQB_bwQbTJKjn2DtUIiHY3lroLF3n36E5b14ldHrR07j17qq3PmqYi29YnfTTgm-J_nqPzIf3EDqQoYuGfag4VeZVOiB529Fd-WCGevnq9fGGnpDfqkPh2ueKbE5D45f-PRKcRB2e3dMqKvOQ1J9roK6WndJ35gglPORX94X7C7h931e6eoTRnUDqtDNqbkUutC0Z48S_NnzUAszc=w373-h800-no


    As you can see, mine is selected to VZW/VZW which is the XXX/YYY portion of the XXX/YYY/ZZZ combo (again, ZZZ should not change. Only having root can change this!)

    You can now select a CSC and then click install at the bottom. This will reboot the phone and should not wipe any data.

    *Pro Tip*
    At the bottom of the CSC screen, there is an option that says Don't change carrier(for DEV/QA). Well, you know how when you change the SIM on the U1 firmware, the phone detects and new SIM and reboots to apply the new carrier settings? You can choose this and select install and get a popup showing ENABLED and the phone won't reboot, allowing you to choose the CSC and keep it with whatever SIM is installed.
    SRRgdfXbgVrlX0gi39nrNvCOP5fUpxpsFwx07Uizs4rArx-_Os2b5uiqVeDLnYEQF41bX5NGF4wAWvIt47XdYB5hpIiIgVDqf-Ke7YLX4UhhSDwOjsD8s-jAm1B6uCUw0RS8Fqq1MMH8k9yGZ_EalB5aT1AFCdF1NQjObWcz-is4vo4Cw_PqVdNVvs2zNA70lelgxoBaoLEcqPgATGtWDqj-OyUMInPsXuAEvYrYSgFJmi24zqxTKxbGOPJLyX_xtYBKgcq-EM8fDavpsWdwfAXKG-h9HpaGjeAJU0kBpyvCS_Bpr1BQrS434VWANjlGgK_oXM56Elzv9X9-AMplSVerXoGXZHi95csmxfJS4y1GCBpYv0uOkCc-ptlI9eW7keuRPSlvir0al1RVrAUn8lLQkGKU4nwS3zhoP61qx8cShoLumwqLKX9gJd4RBEb3YhxGu_iaP4MHOAgXlAgQSkNCcRNDDOoIRkd1EbdtHb91oe2IFWBxObET7nhzlksWzEQWyHVdZ06XkKLokjjiTEpzZk3gzDbnRA46HTazxsGe4KvD2s4YSZqZbMUMxhpyB7u2j3WIyJLsYTx5ledUzfLae5r0suTB7uraTAHVRS4n82NfwdvrbvTgeJL_G9f6rSVKKd0h8Srhb8vjbygcvJzzxHn2t2BE_aleUxsmE4NZNI8mQW5FJr00UmQS=w373-h800-no


    Here is a list of the available CSCs on the U1 and the Carriers I have found:
    ACG=NexTech/C-Spire
    ATT=AT&T
    AIO=Cricket
    LRA=Bluegrass Cellular (possibly other smaller carriers also)
    VZW=Verizon
    BST=Boost Mobile
    TMB=Tmobile
    TMK=MetroPCS
    TFN=Tracfone
    USC=U.S. Cellular
    XAA=Unlocked Non-Branded (Google FI is an example)
    XAR=Cellular South
    XAS=Samsung Unbranded Sprint
    CCT=Xfinity Mobile
    CHA=Spectrum (Charter)
    XAG=Some MVNOs that use TMO, like Mint (confirmation needed)
    ATC=Unknown
    FKR=Unknown
    GCF=Global Certification Forum
    WWD=World Wide Device
    SPR=Sprint
    DSH=Dish Network

    I hope everyone finds this guide helpful and I will add/change any information as it is discovered.
    11
    Just check the code on my N9810 BRI
    This method only works on Qualcomm versions
    I use *#*#276633683782#*#* on Google phone dialer
    and it brings up a service mode screen.

    Press [5] RF Test and choose [2] PREF MODE SET
    (or other options also works )
    It will show Please use *#2263# for mode set
    Then just tap three dots on right top menu and choose back
    It will bring you back to the main menu.

    4
    I happen to have quite a few Note 20 Ultras available for testing, including two that work (BL Unlocked, rooted SM-N9860-CHC and a SM-N986U1-XAA) as well as two that are disassembled (SM-N9860-TGY and SM-N986U1-TMB). If you have any hardware questions or tests you'd like me to run let me know and I should be able to make it happen.

    P.S. Draiter is correct about the solder markings differentiating the variants but they are not actually bridging any pads to enable features but rather are just manufacturing markings to label which model phone the board is for. I can also vouch that there is more to bands than just software differences. The US SD models have MMWave antennas that the CHC/TGY/BRI models don't have. And as far as cross flashing CP modem files in odin I can confirm that the phones absolutely throw a fit when attempting to flash "incorrect" CP files. There's apparently a version check that occurs similar to BL files in that you can only upgrade modem versions and I learned the hard way that flashing a lower modem revision CP resulted in a phone that booted but would soon display a popup during setup saying "no IMEI/MEID found" followed by a hard shutoff and bootloop!
    3
    *#*#27663368378#*#* still works for me on TMO N20U (unlocked) after Android 11 update
    but *#272*IMEI# doesn't bring up CSC menu which was available before Android 11 update.
    Following code works to bring up CSC menu.
    Dialed *#*#27262826#*#* on my unlocked Tmobile using google phone app
    3
    Here are some other options in service menu I have changed to improve performance. I have seen it not only help 5G, but LTE as well. I will update the guide soon with full instructions.
    Hi, mellojosh. Great thread. Unfortunately the screen grabs you had in post #25 all disappeared during the forum migration. If there is any way that you can replace them that would be epic. Thanks. 👍