Develop Bugs

Switching from ATT to TMobile, questions inside

Hello, I'm currently using a Galaxy s9+ on ATT and plan on switching to Tmobile this week. Besides unlocking the phone do I have to do anything else for the phone to take advantage of TMobile? Do I have to flash TMobile firmware or anything like that in order for the phone to work properly and if so how, I've been out of the flashing game for a LONG time .

No you don't have to flash t mobile rom as I know when you put a new sim the phone reboots and sets the phone up for that carrier that's what it does on my s9 but mine the unlocked one so I got wifi calling with t mobile sim card in my phone

T mobile
The screen shots should show up

same boat but need to flash TMB image
okay hear's the deal, i am in the same boat moved to T-Mobile few days back and i have a Vzw branded S9+. i was of the opinion that things would workout great, but my area has poor t-Mobile network and i have been unsuccessfully attempted to flash TMB firmware on this phone. I have tried just about all combinations, and every-time the flash is done it boots back as a brand new Vzw phone and looks for a Vzw sim. I insert the TMB SIM and things work but not WIFI calling. Any leads?

riyengarxda said:
okay hear's the deal, i am in the same boat moved to T-Mobile few days back and i have a Vzw branded S9+. i was of the opinion that things would workout great, but my area has poor t-Mobile network and i have been unsuccessfully attempted to flash TMB firmware on this phone. I have tried just about all combinations, and every-time the flash is done it boots back as a brand new Vzw phone and looks for a Vzw sim. I insert the TMB SIM and things work but not WIFI calling. Any leads?
Click to expand...
Click to collapse
What odin you use??

1.13.1 patched.
---------- Post added at 02:54 AM ---------- Previous post was at 02:51 AM ----------
Some more details if that helps..
Paid $24 to Sammobil, went through the flashing process and nothing changed. Did this almost 5 times but seems VZW keeps haunting me. Am I doing something wrong? I downloaded the latest firmware RB8 from Aug 2018 for TMB via sammobile flashed the 4 files AP, BT,CP and CSC. Everything went perfect but when it boots back Damn the same old VZW and the OS says u have a non vzw sim. I even flashed the userdata with the other four and separately but no luck. Do we have any success stories and how we dis this correctly? Using Odin 1.13.3 patched version. Tried to downgrade but that failed.

Use 3.13 I believe

Rally517 said:
Use 3.13 I believe
Click to expand...
Click to collapse
Yes sorry typo error, 3.13.1_3B

Not trying to start a new thread with something similar so I'm just gonna post underneath this one. I have an AT&T S9 that is sim unlocked and all but, for the life of me I can't get it to work on Verizon. I've tried changing the bands in the *#*#3696#*#* menu and all I get is, is data. I tried flashing ARG7 unlocked I believe and it still booted with all the AT&T stuff loaded. The build number now shows ARG7 instead of ARG8. I don't know if there's a specific odin / firmware I need to flash in order to be able to get it right. I've been hunting for hours and flashing and I'm at a loss. Thank you guys in advance.

riyengarxda said:
okay hear's the deal, i am in the same boat moved to T-Mobile few days back and i have a Vzw branded S9+. i was of the opinion that things would workout great, but my area has poor t-Mobile network and i have been unsuccessfully attempted to flash TMB firmware on this phone. I have tried just about all combinations, and every-time the flash is done it boots back as a brand new Vzw phone and looks for a Vzw sim. I insert the TMB SIM and things work but not WIFI calling. Any leads?
Click to expand...
Click to collapse
All the carrier stuff is located in the CSC from the flash.
Side note: from what I've read, Verizon locks down the bands and whatnots that stop TMobile stuff from functioning, like WiFi calling.
I've seen people get it working but not the video calls.

thegreatkazoo said:
All the carrier stuff is located in the CSC from the flash.
Side note: from what I've read, Verizon locks down the bands and whatnots that stop TMobile stuff from functioning, like WiFi calling.
I've seen people get it working but not the video calls.
Click to expand...
Click to collapse
Thanks, I really don't care about video calls but WIFI calling is a real need.. any leads?

thegreatkazoo said:
All the carrier stuff is located in the CSC from the flash.
Side note: from what I've read, Verizon locks down the bands and whatnots that stop TMobile stuff from functioning, like WiFi calling.
I've seen people get it working but not the video calls.
Click to expand...
Click to collapse
All my functions work. Video calling etc etc. Unlocked s9. First I az on Boost mobile. Switched to metro. Flashed tmb everything works.

riyengarxda said:
Thanks, I really don't care about video calls but WIFI calling is a real need.. any leads?
Click to expand...
Click to collapse
There a thread around here that talks about how to get the TMobile services but WiFi calling is all they could get to work. You have to flash the CSC (home partition) from TMobile is what I've heard. I've also heard, you can put in a TMobile Sim and it'll just work. But, I think that might be limited to "factory unlocked" phones.

thegreatkazoo said:
There a thread around here that talks about how to get the TMobile services but WiFi calling is all they could get to work. You have to flash the CSC (home partition) from TMobile is what I've heard. I've also heard, you can put in a TMobile Sim and it'll just work. But, I think that might be limited to "factory unlocked" phones.
Click to expand...
Click to collapse
Do you have the thread link? I tried just about as many I could read up..

riyengarxda said:
Do you have the thread link? I tried just about as many I could read up..
Click to expand...
Click to collapse
I'm at work but I'll be off in a bit and I'll hunt it down once I get home.
If I'm not mistaking, it's the one that talks about flashing the u fw to the u1.

riyengarxda said:
Do you have the thread link? I tried just about as many I could read up..
Click to expand...
Click to collapse
https://forum.xda-developers.com/ga...n8-s8x-s9x-oreo-usa-t-mobile-efs-csc-t3772385
Here you go. There's a version 3 on OP web site. Look up my posts there.

Docmjldds said:
https://forum.xda-developers.com/ga...n8-s8x-s9x-oreo-usa-t-mobile-efs-csc-t3772385
Here you go. There's a version 3 on OP web site. Look up my posts there.
Click to expand...
Click to collapse
Read through all the 16 page thread and found very useful comments from you on usage of V3 detonator and Csc changer. I stand confused over just 2 questions;
1. Do I have to root my s9+ which is from vzw
2. It talks about F and FD variant while I have a u variant running snapdragon.
Show me some light .:angel:

riyengarxda said:
Read through all the 16 page thread and found very useful comments from you on usage of V3 detonator and Csc changer. I stand confused over just 2 questions;
1. Do I have to root my s9+ which is from vzw
2. It talks about F and FD variant while I have a u variant running snapdragon.
Show me some light .:angel:
Click to expand...
Click to collapse
I'm on Exynos S9 and rooted. Doubt this will work on a Snapdragon device. Sorry

Docmjldds said:
I'm on Exynos S9 and rooted. Doubt this will work on a Snapdragon device. Sorry
Click to expand...
Click to collapse
Yup exactly my taught... thank you for all the insights..

Not getting connected to 4G in the US on Global Rom

Hi Guys,
Spend a bunch of time with AT&T trying to get this phone on the data network here in the USA. When the phone first boot I can get on the data network for about 15 seconds and then it seems to get blocked or something.
I'm just wondering if this is because its the fake global rom? 9.6.4.0.
It shows as connected and on 4G for AT&T but only calls and texts work, no data. AT&T said that the IMEI number was showing incorrectly and that they had to add it to their system, so it sounds like this is a carrier issue and not ROM issue but just wanted to be sure.
Also as far as the sim card slots, I wanted to use an sd card so that means I need to put the sim in the 2nd sim slot. In the phone it shows 2 IMEI numbers, one of which is 14 characters and the other is 15 characters. AT&T made it sound like a 14 character IMEI was invalid in the US. The odd part is that the IMEI numbers changes slots as I move the SIM card around. the 14 character IMEI number will move to where ever the SIM is installed. Not sure if this matters or not either.
If I reboot the phone I get data for like 15 seconds again and then is stops.
Any ideas on this one? Just wanted to make sure this isn't something up with the fake rom installed (phone was already unlocked when I got it)

So just for good measure I went ahead and flashed the global 9.6.6.0 rom that was release today.
AT&T cannot seem to get this phone activated on their network at all... I get 4G showing in the notification bar, but I cannot get any voice or data.
I know some of you guys have this phone running on AT&T, are you using global roms? Could that have anything to do with me not getting signal? Is it worth trying to flash a chinese rom as well?
I sort of feel this is a carrier issue, but I am certainly not sure.

omniphil said:
So just for good measure I went ahead and flashed the global 9.6.6.0 rom that was release today.
AT&T cannot seem to get this phone activated on their network at all... I get 4G showing in the notification bar, but I cannot get any voice or data.
I know some of you guys have this phone running on AT&T, are you using global roms? Could that have anything to do with me not getting signal? Is it worth trying to flash a chinese rom as well?
I sort of feel this is a carrier issue, but I am certainly not sure.
Click to expand...
Click to collapse
Did you try the volte enabler in dialer? *#*#86583#*#*
Also, are your apn settings correct?

The modem of the global rom is currently broken, nothing will help.
I suggest installing 9.6.11.0 China stable (no ARB) from fastboot and then downgrade to 9.6.6.0 Global using the antirollback method
your modem will work perfectly

omer919 said:
The modem of the global rom is currently broken, nothing will help.
I suggest installing 9.6.11.0 China stable (no ARB) from fastboot and then downgrade to 9.6.6.0 Global using the antirollback method
your modem will work perfectly
Click to expand...
Click to collapse
Ok, I will certainly give that a whirl. It certainly does feel like the modem is not working...
Do I have to downgrade to 9.6.6.0? No harm in staying on the 9.6.11.0 china rom? (Or does it not support English at all?)
I have been unsuccessful getting flashing to work over fastboot, so I must be missing something there. Can I just flash via TWRP? that's already installed and working?

opasha said:
Did you try the volte enabler in dialer? *#*#86583#*#*
Also, are your apn settings correct?
Click to expand...
Click to collapse
Yup, I did try both of those....

omniphil said:
Ok, I will certainly give that a whirl. It certainly does feel like the modem is not working...
Do I have to downgrade to 9.6.6.0? No harm in staying on the 9.6.11.0 china rom? (Or does it not support English? at all)
I have been unsuccessful getting flashing to work over fastboot, so I must be missing something there. Can I just flash via TWRP? that's already installed and working?
Click to expand...
Click to collapse
I have been using China Stable 9.6.11.0. and it's 95% english. Works fine as a daily driver.

4z4 said:
I have been using China Stable 9.6.11.0. and it's 95% english. Works fine as a daily driver.
Click to expand...
Click to collapse
Excellent, Ok, I will flash the 9.6.11.0 in TWRP and hopefully that makes the mode work again.
Thank you guys!

Ok, I now have a working radio after flashing the 9.6.11.0 !!!!! Thank you guys! Data and Voice are now working on AT&T.
So if I wanted to go to the global 9.6.6.0, can i just flash that over this in TWRP?

omniphil said:
Ok, I now have a working radio after flashing the 9.6.11.0 !!!!! Thank you guys! Data and Voice are now working on AT&T.
So if I wanted to go to the global 9.6.6.0, can i just flash that over this in TWRP?
Click to expand...
Click to collapse
Yes, that's what omer919 said would work.

opasha said:
Yes, that's what omer919 said would work.
Click to expand...
Click to collapse
Sounds too easy, but i'll give it a try, lol....
I figure that encrypted partition will be problematic...
I still have the issue where TWRP never stays, I have to flash it via ADB everytime i want to use it. Anf then it only works once and is gone.
EDIT, yeah, that certainly didnt work. Phone boots to a password screen, I really hate encryption and this is why...

Try this:
https://forum.xda-developers.com/mi-max-3/help/help-t3839214

samkatta said:
Try this:
https://forum.xda-developers.com/mi-max-3/help/help-t3839214
Click to expand...
Click to collapse
I'm not getting anything like that. I just did a format of the data and flashed 9.6.6.0. Its just sitting at the android loading screen now, so that didnt work either.
But at least I know that the chinese rom does work. That's a plus, now just to get over to global rom somehow...

wow, it works with att? u getting H or LTE? what city u in? i want to check the city bands

Again, your modem is broken, nothing will help on software part.
if you want china rom, with china bloatware no multilanguage and GAPPS not working good go for it and just stay on china stable.
if you want to install global rom again while having a working modem follow the guide: here

ryanllts said:
wow, it works with att? u getting H or LTE? what city u in? i want to check the city bands
Click to expand...
Click to collapse
I'm in New Hampshire. Its just 4G in this area, but I suspect it will connect to LTE in the appropriate areas.

I have a question regarding 4g. My device shows only LTE instead of 4g. Seems to have quick connection. In theory they are the same but just wondering if anyone having the same?

shadow78 said:
I have a question regarding 4g. My device shows only LTE instead of 4g. Seems to have quick connection. In theory they are the same but just wondering if anyone having the same?
Click to expand...
Click to collapse
I go between 4G and LTE areas (home and work). The phone shows the appropriate connection at each location, They are definitely different things.

omniphil said:
I go between 4G and LTE areas (home and work). The phone shows the appropriate connection at each location, They are definitely different things.
Click to expand...
Click to collapse
Thx what fw are you using? I remember when I had the chinese stable and even before the EU I had 4g showing up. But now even when I go to settings I can only chose LTE and 3g. No 4g option.

shadow78 said:
Thx what fw are you using? I remember when I had the chinese stable and even before the EU I had 4g showing up. But now even when I go to settings I can only chose LTE and 3g. No 4g option.
Click to expand...
Click to collapse
I had the 9.6.4.0 and the 9.6.6.0 global roms, those both had broken modems, no internet access.
I also tried the trick of putting on the chinese rom 9.6.11.0 and then flashing over to the firmware less 9.6.6.0 global. Still broken modem.
The only way I can get working data is to use a chinese rom. These have all worked.
I was on 8.8.9 miui 10, which I then upgraded to 8.9.6. After that I dirty flashed the xiaomi.eu 8.9.6 rom over that. All of those have working radios.
I guess i'm not too concerned about flashing the newer anti-rollback roms anymore, since there is a guide on how to roll back if you need to. But so far on the chinese miui 10 roms the only issue I seem to have is Android Auto not working and Textra (3rd party text app) not keeping its notification alive.

Can't update AT&T G8

I recently bought an AT&T G8 on eBay and no matter what I try, I can't update it. It's still on the factory update. I've had an activated AT&T SIM in it for several days, tried using other SIMs, factory resetting a few times, but I still get the same error that says it can't update or there's just no update. I've tried calling tech support there and going into a store, but they were out of ideas too. Does anyone have a link to any update to try installing or any ideas for how to get it to update?

calxk713 said:
I recently bought an AT&T G8 on eBay and no matter what I try, I can't update it. It's still on the factory update. I've had an activated AT&T SIM in it for several days, tried using other SIMs, factory resetting a few times, but I still get the same error that says it can't update or there's just no update. I've tried calling tech support there and going into a store, but they were out of ideas too. Does anyone have a link to any update to try installing or any ideas for how to get it to update?
Click to expand...
Click to collapse
from which country do you come from?

rmato said:
from which country do you come from?
Click to expand...
Click to collapse
I'm in the US

calxk713 said:
I recently bought an AT&T G8 on eBay and no matter what I try, I can't update it. It's still on the factory update. I've had an activated AT&T SIM in it for several days, tried using other SIMs, factory resetting a few times, but I still get the same error that says it can't update or there's just no update. I've tried calling tech support there and going into a store, but they were out of ideas too. Does anyone have a link to any update to try installing or any ideas for how to get it to update?
Click to expand...
Click to collapse
Try LG Bridge. I had an update that stalled and then wouldn't offer me it again, connected to LG Bridge and poof done.

Install Android 10 manually with lgup. Flash android 10 kdz

trouble. said:
Install Android 10 manually with lgup. Flash android 10 kdz
Click to expand...
Click to collapse
This works on the g8? Given the lack of options we have with being able to recover the device I really don't want to brick.

p3tr0s said:
This works on the g8? Given the lack of options we have with being able to recover the device I really don't want to brick.
Click to expand...
Click to collapse
Yeah it works

p3tr0s said:
This works on the g8? Given the lack of options we have with being able to recover the device I really don't want to brick.
Click to expand...
Click to collapse
It will not brick your phone. It's very simple. Get the kdz for your at&t model. Install a dev patched lgup and flash.

trouble. said:
It will not brick your phone. It's very simple. Get the kdz for your at&t model. Install a dev patched lgup and flash.
Click to expand...
Click to collapse
Not to a complete noob here, I've been out of the flashing game for a while but I haven't been successful in finding any online images for the at&t model. Any tips on finding one?

p3tr0s said:
Not to a complete noob here, I've been out of the flashing game for a while but I haven't been successful in finding any online images for the at&t model. Any tips on finding one?
Click to expand...
Click to collapse
What's your model number and where do u live?

trouble. said:
What's your model number and where do u live?
Click to expand...
Click to collapse
LM-G820UM it's the at&t model in the United States.

p3tr0s said:
LM-G820UM it's the at&t model in the United States.
Click to expand...
Click to collapse
https://lg-firmwares.com/downloads-file/21864/G820UM20b_00_USC_US_OP_0110
There u go.

trouble. said:
https://lg-firmwares.com/downloads-file/21864/G820UM20b_00_USC_US_OP_0110
There u go.
Click to expand...
Click to collapse
That's not it. I think at&t doesn't publish kdzs.i have the same issue with Sprint

antintin said:
That's not it. I think at&t doesn't publish kdzs.i have the same issue with Sprint
Click to expand...
Click to collapse
That's my understanding as well. I'm getting the run around from at&t, cricket, and LG with them pointing the finger at each other playing the blame game. Seriously annoying... The G8 is a beast but if it's like this I might just stick with my pixel 3a. I appreciate the info though from everyone.

antintin said:
That's not it. I think at&t doesn't publish kdzs.i have the same issue with Sprint
Click to expand...
Click to collapse
It is! It's the same model kdz. How can u say that's not it?

trouble. said:
It is! It's the same model kdz. How can u say that's not it?
Click to expand...
Click to collapse
That's the us open

so has anyone flashed this firmware manually via LGUP to their AT&T g8 and was successful? does everything get wiped?

So I've bought a couple of these att LG g8. The problem was that I am on cricket so no updates. This has been a fool proof way I've found to get the updates moving.
I put in an activated (I didn't add any money to my att account) att sim, 10 bucks from Walmart. I issue a factory reset and skip all setup (except connecting to WiFi). Check update as soon as I am through setup. If it works great ,if not repeat. It's worked on 3 phones so far.

geminihc said:
so has anyone flashed this firmware manually via LGUP to their AT&T g8 and was successful? does everything get wiped?
Click to expand...
Click to collapse
No cross flash is not possible...

trouble. said:
Install Android 10 manually with lgup. Flash android 10 kdz
Click to expand...
Click to collapse
Do you have the KDZ link?

Dont know what stock Firmware my phone needs

Good Morning,
So this is the story, I was suddenly having issues with Cell service people were not hearing me I felt like I had to reset the phone and wipe it all so I thought I might as well ROOT it when it came to downloading the firmware I was a bit lost did not know what was the correct one was i threw out the box,
I flashed one but still have this cell issue I feel like its not using all the bands... I have Tmobile and I do not know if the issue is I am flashing wrong firmware.
So 2 questions
how would I know if I am flashing the correct firmware?
And how would I know if that is my issue ?
Please Someone Advise.

tzvblsm said:
Good Morning,
So this is the story, I was suddenly having issues with Cell service people were not hearing me I felt like I had to reset the phone and wipe it all so I thought I might as well ROOT it when it came to downloading the firmware I was a bit lost did not know what was the correct one was i threw out the box,
I flashed one but still have this cell issue I feel like its not using all the bands... I have Tmobile and I do not know if the issue is I am flashing wrong firmware.
So 2 questions
how would I know if I am flashing the correct firmware?
And how would I know if that is my issue ?
Please Someone Advise.
Click to expand...
Click to collapse
I would test another carrier first, or the same carrier in another area. Also test with different people in different areas. This is most often an issue on the carrier side, not the device.
So my advice: make sure your issue is the device. Only after that we can talk about flashing another ROM.

Thanks @arsradu for your quick reply Its definitely not the carrier I just am not sure what the problem is, I was thinking each firmware has its own optimizations for the bands it should use,
I bought it on amazon USA
And currently flashed
TROIKA_RETAIL_10_QSBS30.62-17-13_subsidy-DEFAULT_regulatory-DEFAULT_CFC.xml
I tried using LMSA to restore my phone to factory settings and it gives me an error I wish I can just go back to stock clean.

tzvblsm said:
Thanks @arsradu for your quick reply Its definitely not the carrier I just am not sure what the problem is, I was thinking each firmware has its own optimizations for the bands it should use,
I bought it on amazon USA
And currently flashed
TROIKA_RETAIL_10_QSBS30.62-17-13_subsidy-DEFAULT_regulatory-DEFAULT_CFC.xml
I tried using LMSA to restore my phone to factory settings and it gives me an error I wish I can just go back to stock clean.
Click to expand...
Click to collapse
Assuming you bought a US model, which works on all major carriers, your version should be RETUS.
With the bat file that was provided here in the forum, you should be able to fast boot flash it.

tzvblsm said:
Thanks @arsradu for your quick reply Its definitely not the carrier I just am not sure what the problem is, I was thinking each firmware has its own optimizations for the bands it should use,
I bought it on amazon USA
And currently flashed
TROIKA_RETAIL_10_QSBS30.62-17-13_subsidy-DEFAULT_regulatory-DEFAULT_CFC.xml
I tried using LMSA to restore my phone to factory settings and it gives me an error I wish I can just go back to stock clean.
Click to expand...
Click to collapse
It can be the ROM, as well. In my experience though it’s usually not the case.
Anyway, what’s your device model? Is it xt2013-4? Did you make a backup of your original ROM so you can restore it later on?
Also, what is the error you get when trying to use LMSA to restore?

Yes my model number is xt2013-4 no i did not make a backup I uploaded a screenshot of the error message. and I guess I will try reatilUS I tried the simple retail option the last one not sure what retail and retail us differences are,
https://imgur.com/17b3ltY

tzvblsm said:
Yes my model number is xt2013-4 no i did not make a backup I uploaded a screenshot of the error message. and I guess I will try reatilUS I tried the simple retail option the last one not sure what retail and retail us differences are,
https://imgur.com/17b3ltY
Click to expand...
Click to collapse
RETUS with the above linked bat has worked fine for a XT2013-04 I have worked with, I assume it would with yours too :good:
I cannot speak to the assistant error though, never used it...
Side note: don't forget to add the code line for the 10th chunks to the bat.

Does Any one know what are the differences between Firmware's that are made for this phone ? for example
AMZ
Retail
Reatus

tzvblsm said:
Does Any one know what are the differences between Firmware's that are made for this phone ? for example
AMZ
Retail
Reatus
Click to expand...
Click to collapse
AMZ is the Amazon Ads model,
Retail can be US retail with different bands.
Retus is what I flashed in the past on a US phone that worked with all 4 carriers and it never had any issues.

Tried to flash G988W firmware onto my G988U1 phone. SIM card not recognized

I live in Canada. I purchased an S20 Ultra off a seller on Canadian best buy (open box). I assumed it'd be a Canadian variant, but it was an unlocked US version (U1 firmware). OK whatever, but it meant my Samsung Pay doesn't work, along with a few other calling features.
I downloaded the patched Odin, downloaded the G988W firmware (with XAC CSC) with Frija, added the appropriate files to Odin (used Home CSC), and flashed it. The flashing itself went fine, but when I went to re-insert my SIM...nothing. It didn't even error out and say "No SIM Detected", I just had no coverage, and in SIM manager, both slots were empty.
Freaked out, and eventually flashed back to G988U1/XAA and thank Christ it works now. But my question is...why?
I dug though this forum before doing it to try and anticipate any issues. Followed the instructions to the letter, nowhere said this would be an issue. Couldn't even find any relevant support questions for this issue on this model. Not sure if it's a new development, but I absolutely don't want to risk messing my phone up further if I reattempt.
Bonus question: My CSC info is: XAA/XAA,XAA/SPR. Does that mean that it was originally a Sprint model phone, someone's flashed the firmware to an unbranded version, then sold it off as New (Open Box)?

You can't just flash a firmware from a different phone. The hardware is different, so the way to communicate with it is different. You're lucky it even booted, I wouldn't have expected that even. You're simply stuck with the original firmware and CSC list. Or, maybe you could try with custom ROMS but I wouldn't be so sure about it. Either way, you'll have to use a ROM/firmware that is built for your phone (G988U1).

Mwyann said:
You can't just flash a firmware from a different phone. The hardware is different, so the way to communicate with it is different. You're lucky it even booted, I wouldn't have expected that even. You're simply stuck with the original firmware and CSC list. Or, maybe you could try with custom ROMS but I wouldn't be so sure about it. Either way, you'll have to use a ROM/firmware that is built for your phone (G988U1).
Click to expand...
Click to collapse
Huh I thought the actual hardware between U1 and W was the same? They're both Snapdragons. Besides I've seen other posts of people doing the same (tbh, they were going from W to U1, but still)

Mwyann said:
You can't just flash a firmware from a different phone.
Click to expand...
Click to collapse
Oh but you CAN.
U, U1, and W have all been cross-flashable ever since Samsung first introduced universal hardware, starting with the S8

Jetrel1 said:
Bonus question: My CSC info is: XAA/XAA,XAA/SPR. Does that mean that it was originally a Sprint model phone, someone's flashed the firmware to an unbranded version, then sold it off as New (Open Box)?
Click to expand...
Click to collapse
Probably. Very common for online sellers to do.
The key probably lies in what the CSC shows as after flashing W firmware. If it stays as XAA, changing the CSC manually to a Canadian one could possibly make it work

iBowToAndroid said:
Oh but you CAN.
U, U1, and W have all been cross-flashable ever since Samsung first introduced universal hardware, starting with the S8
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I thought so too, lol
Any thoughts on why my flash caused the SIM issue? Did I maybe just install the wrong version? I don't think I did, I used Frija
Some further research led me to the subject of accidentally mucking up the modem firmware which I might have done

Jetrel1 said:
I thought so too, lol
Any thoughts on why my flash caused the SIM issue? Did I maybe just install the wrong version? I don't think I did, I used Frija
Some further research led me to the subject of accidentally mucking up the modem firmware which I might have done
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See my other post above

iBowToAndroid said:
See my other post above
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My bad I didn't even compute. Thanks!

Jetrel1 said:
I live in Canada. I purchased an S20 Ultra off a seller on Canadian best buy (open box). I assumed it'd be a Canadian variant, but it was an unlocked US version (U1 firmware). OK whatever, but it meant my Samsung Pay doesn't work, along with a few other calling features.
I downloaded the patched Odin, downloaded the G988W firmware (with XAC CSC) with Frija, added the appropriate files to Odin (used Home CSC), and flashed it. The flashing itself went fine, but when I went to re-insert my SIM...nothing. It didn't even error out and say "No SIM Detected", I just had no coverage, and in SIM manager, both slots were empty.
Freaked out, and eventually flashed back to G988U1/XAA and thank Christ it works now. But my question is...why?
I dug though this forum before doing it to try and anticipate any issues. Followed the instructions to the letter, nowhere said this would be an issue. Couldn't even find any relevant support questions for this issue on this model. Not sure if it's a new development, but I absolutely don't want to risk messing my phone up further if I reattempt.
Bonus question: My CSC info is: XAA/XAA,XAA/SPR. Does that mean that it was originally a Sprint model phone, someone's flashed the firmware to an unbranded version, then sold it off as New (Open Box)?
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I Just did exactly the same and got a tmobile variant but want the W preferably the samsung factory rom not a carrier one. Which guide did you follow? I found this for the 21 Ultra and expect the steps to be similar https://forum.xda-developers.com/t/...-samsung-unlocked-bloatfree-firmware.4224423/

What calling features don't work in Canada? I have a W variant, live in Canada, and want an U1 to get esim working. I am also looking for a guide to follow to flash my phone.

funrunner said:
What calling features don't work in Canada? I have a W variant, live in Canada, and want an U1 to get esim working. I am also looking for a guide to follow to flash my phone.
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Samsung Pay doesn't work - that's a big one for me, it's a pain in the **** losing that. Will only accept US ZIP codes when setting up.
Caller ID doesn't work
That extra info you get when texting (like seen/read stuff) doesn't work in the native Samsung text app, you have to use google messages (yeah, no)
I'm sure there's other stuff but those are the main ones