Develop Bugs

[QUEST] 4G LTE working T-Mobile radio/modem on AT&T Note 2 or Viceversa

Is there currently a working T-Mobile modem that gets 3G on T-Mobile for the AT&T note 2? Instead of the typical Edge. (same as on Note 1) I have my AT&T Note 1 with 3G on T-Mobile... Any releases yet for the Note 2? I already ordered the dual sim card adapter for the Note 2...
Sent from my SGH-I957 using XDA Premium HD app

TEKHD said:
Is there currently a working T-Mobile modem that gets 3G on T-Mobile for the AT&T note 2? Instead of the typical Edge. (same as on Note 1) I have my AT&T Note 1 with 3G on T-Mobile... Any releases yet for the Note 2? I already ordered the dual sim card adapter for the Note 2...
Sent from my SGH-I957 using XDA Premium HD app
Click to expand...
Click to collapse
I can't seem to get a straight answer on this either. I have been searching for 2 days now and I haven't been able to find any solutions. I have jediX on my unlocked AT&T phone with a T-Mobile sim and all I get is Edge. ive tried to put on the T-Mobile Radio and it just boot loops me.
I may have to try and find someone that wants to trade phones with me at this point.

I believe that most of the T889 roms have a radio built in.. Have you tried that?

papabear said:
I believe that most of the T889 roms have a radio built in.. Have you tried that?
Click to expand...
Click to collapse
yes i have, when i flash other roms that say the radio is included, it still shows the AT&T radio under settings>device info.
I have Jedi -X4 for Build number but,
i317UCALJ2 listed as the Baseband Version.
Model number shows SGH-T889.
if i try to flash a the T-mobile Radio, it just boot loops.

daver1 said:
yes i have, when i flash other roms that say the radio is included, it still shows the AT&T radio under settings>device info.
I have Jedi -X4 for Build number but,
i317UCALJ2 listed as the Baseband Version.
Model number shows SGH-T889.
if i try to flash a the T-mobile Radio, it just boot loops.
Click to expand...
Click to collapse
I have only just started looking into this myself and was expecting a working T-mobile radio that can be used on AT&T (or Rogers) to be floating around, considering they are all using hardware revision JRO03C.
Any help would be appreciated.

trade
daver1 said:
I can't seem to get a straight answer on this either. I have been searching for 2 days now and I haven't been able to find any solutions. I have jediX on my unlocked AT&T phone with a T-Mobile sim and all I get is Edge. ive tried to put on the T-Mobile Radio and it just boot loops me.
I may have to try and find someone that wants to trade phones with me at this point.
Click to expand...
Click to collapse
I am dealing with the same issue the other way (tmobile on att network, no lte), so if you ever look to trade, let me know.

Yjojimboo said:
I am dealing with the same issue the other way (tmobile on att network, no lte), so if you ever look to trade, let me know.
Click to expand...
Click to collapse
Please clarify: you have a T889 (TMo N2) device using an AT&T SIM, in an area confirmed to have AT&T LTE service, and you're getting no LTE? Have you tried flashing the modem package off an i317 (AT&T N2) onto your device to see if LTE gets activated that way?

Did you tried *#2263# and then u can choose lte 17 for att.good look ..

I didn't try those two, but I will right now. Tried another method using a long input string, but it didn't work.

Yep the *#*#4636#*#*doesnt work on theese roms, however the*#2263# works on the x5 rom but not on the 4.1.2 lk7 roms.on theese roms u can choose lte and hspa from mobile settings but there is not lte only option.do u have a succes with the code ,by the way you can try hspa plus on 1900 mhz on tmobile card with that code too.i tryed it and I can confirm it is 21mbits for now.

distortedloop said:
Please clarify: you have a T889 (TMo N2) device using an AT&T SIM, in an area confirmed to have AT&T LTE service, and you're getting no LTE? Have you tried flashing the modem package off an i317 (AT&T N2) onto your device to see if LTE gets activated that way?
Click to expand...
Click to collapse
000, I might try that
Sent from my SGH-T889 using xda premium

TMobile Modem on Galaxy Note 2 ATT i317
I am in the same situation as the OP. Looking to flash a T889 modem onto an ATT Galaxy Note 2 (i317) similar to the solution for Galaxy Note 1 ATT (i717) users using Tmobile network (by flashing a modified Amaze? modem).
Anyone successful in getting 3g TMobile speeds with their Galaxy Note I317?

browniegirl said:
000, I might try that
Sent from my SGH-T889 using xda premium
Click to expand...
Click to collapse
LTE should work if you do that, but make sure your IMEI is still OK, and have a backup phone if you try flashing back the T889 modem. My phone is stuck in a bootloop since trying to go T889V -> I317M -> T889V.

*#197328640#
*#197328640#

TEKHD said:
*#197328640#
Click to expand...
Click to collapse
what can we do with this code?

4g
Darkshado said:
LTE should work if you do that, but make sure your IMEI is still OK, and have a backup phone if you try flashing back the T889 modem. My phone is stuck in a bootloop since trying to go T889V -> I317M -> T889V.
Click to expand...
Click to collapse
I have an AT&T note 2 unlocked working a T-Mobile sim and 4G has been working from the start!

Did you double check that you're in a strictly AWS area, spectrum-wise?
Oh, and quick update: I was able to get the phone to boot with the I317M modem, switch it to diagnostic mode and fix the EFS NV entries. LTE works, not sure about AWS HSPA and not in a position to test.

Darkshado said:
Did you double check that you're in a strictly AWS area, spectrum-wise?
Oh, and quick update: I was able to get the phone to boot with the I317M modem, switch it to diagnostic mode and fix the EFS NV entries. LTE works, not sure about AWS HSPA and not in a position to test.
Click to expand...
Click to collapse
So you have a T889 and flashed I317M Modem and accessed the *#197328640# code and did what exactly? and you are getting LTE on AT&T?
please elaborate.... please...

TEKHD said:
So you have a T889 and flashed I317M Modem and accessed the *#197328640# code and did what exactly? and you are getting LTE on AT&T?
please elaborate.... please...
Click to expand...
Click to collapse
Hello TEKHD,
I have a T889V, but my carrier up here is Virgin Mobile Canada, whose network is technically closer to AT&T's band-wise. DC-HSPA 42 on 850 and 1900 MHz with LTE on Band 4 (AWS).
Reason I got a T889V is because I also keep a T-Mobile SIM for stateside trips, it was a bit cheaper and it leaves the door open to switching to Videotron in addition to the "Big Three".
I first unlocked the phone using the ServiceMode menu method.
I backed up /efs, and this is where I made my first mistake. I know I've been ranting about this for a few days now, you need a proper Qualcomm NV backup.
I usually stick to the Canadian ROMs as they tend to remain closer to their international brethren than the US ones, and also because they don't require tethering fixes. In this case, the T889V ROM also allows switching network modes between GSM, WCDMA and GSM/WCDMA/LTE easily.
I did modify the CSC files to remove the <CscFeature_Setting_DisableNetworkMode>lte</CscFeature_Setting_DisableNetworkMode> line in /system/csc/others.xml and even went so far as making a customized VMC CSC and reapplied that to get all the other little carrier tweaks like FastDormancy. The line is cosmetic only, as I've had it show 4G in the network icon and still get LTE, otherwise it shows 3G, H, H+ and LTE on the T889V. The other place I've seen it have an effect is in the network settings where it'll show GSM/WCDMA/LTE instead of GSM/WCDMA.
I've used Odin before, I have a download jig (two paralleled leftover 620kOhm resistors and a Sparkfun breakout board) and I've tarred my own images before with Cygwin.
To get the necessary files, I downloaded the stock T889V, I317M (Canadian LTE Note II variant, the one that'd actually be sold by VMC if they ever do.) and T889 ROMs from Sammobile.
My initial attempt to flash the I317M modem through Odin (as a standalone image) gave a fail before the phone began the actual writing process, i. e. it transferred the radio image without any issues. Later experiments show that only the T889V modem tar flashes with Odin, the T889 one doesn't either. Same goes for the whole, original Sammobile images, the modem partitions fail if you're cross-flashing.
I then used CWM with an update zip sourced here on XDA that included a "flash_image" binary to flash the 317M LJ2 modem. I used it to prep T889 and 889V zips as well. Rebooted the phone, it connected and gave me LTE, network icon and all. The before and after speedtests went from 3.5 to 35 Mbps. I did check and my IMEI showed 0 instead of, well, my IMEI.
No big deal, or so I thought, I'll just restore /efs in CWM, reflash the T889V modem and carry on. NOT.
The phone immediately started bootlooping, and the only way I initially got it to stop was to flash an N7100 boot.img. The S-Pen didn't work, nor did any networking apart from wifi. Getting QPST to talk to the phone was a bust as well; the hen and the egg.
I tried different combinations and couldn't fix the problem. (My flash counter sits well over 20 now.)
I got another poster (deeznutz1977) to send me his T889 NV backup (sans IMEI) the other day. I later had the idea of reflashing the I317M modem again, which did not boot loop after all (there may have been a matter of wiping /cache and Dalvik cache at the right time).
This time dialcode *#7284#, selecting "Qualcomm USB Settings" then selecting "RNDIS + DM + MODEM" worked. I could get the programs talking with the phone. I inserted my IMEI in deeznutz1977's backup, wrote that to the phone and rebooted.
The phone doesn't bootloop anymore, my IMEI is back, as is service on my current carrier. Plus, this configuration still works with AWS HSPA. The one catch is that bootloops resume if I reflash the T889V modem through either CWM or Odin.
I made a few more speed tests before writing this and managed to get an average 45 Mbps down and 12 up along with a 40 ms ping.
Hope that answered a few of your questions.
Regards,
Darkshado

Darkshado said:
Hello TEKHD,
I have a T889V, but my carrier up here is Virgin Mobile Canada, whose network is technically closer to AT&T's band-wise. DC-HSPA 42 on 850 and 1900 MHz with LTE on Band 4 (AWS).
Reason I got a T889V is because I also keep a T-Mobile SIM for stateside trips, it was a bit cheaper and it leaves the door open to switching to Videotron in addition to the "Big Three".
I first unlocked the phone using the debug menu method.
I backed up /efs, and this is where I made my first mistake. I know I've been ranting about this for a few days now, you need a proper Qualcomm NV backup.
I usually stick to the Canadian ROMs as they tend to remain closer to their international brethren than the US ones, and also because they don't require tethering fixes.
I did modify the CSC files to remove the <CscFeature_Setting_DisableNetworkMode>lte</CscFeature_Setting_DisableNetworkMode> line in /system/csc/others.xml and even went so far as making a customized VMC CSC and reapplied that to get all the other little carrier tweaks like FastDormancy. The line is cosmetic only, as I've had it show 4G in the network icon and still get LTE, otherwise it shows 3G, H, H+ and LTE on the T889V. The other place I've seen it have an effect is in the network settings where it'll show GSM/WCDMA/LTE instead of GSM/WCDMA.
I've used Odin before, I have a download jig (two paralleled leftover 620kOhm resistors and a Sparkfun breakout board) and I've tarred my own images before with Cygwin.
To get the necessary files, I downloaded the stock T889V, I317M (Canadian LTE Note II variant, the one that'd actually be sold by VMC if they ever do.) and T889 ROMs from Sammobile.
My initial attempt to flash the I317M modem through Odin (as a standalone image) gave a fail before the phone began the actual writing process, i. e. it transferred the radio image without any issues. Later experiments show that only the T889V modem tar flashes with Odin, the T889 one doesn't either. Same goes for the whole, original Sammobile images, the modem partitions fail if you're cross-flashing.
I then used CWM with an update zip sourced here on XDA that included a "flash_image" binary to flash the 317M LJ2 modem. I used it to prep T889 and 889V zips as well. Rebooted the phone, it connected and gave me LTE, network icon and all. The before and after speedtests went from 3.5 to 35 Mbps. I did check and my IMEI showed 0 instead of, well, my IMEI.
No big deal, or so I thought, I'll just restore /efs in CWM, reflash the T889V modem and carry on. NOT.
The phone immediately started bootlooping, and the only way I initially got it to stop was to flash an N7100 boot.img. The S-Pen didn't work, nor did any networking apart from wifi. Getting QPST to talk to the phone was a bust as well; the hen and the egg.
I tried different combinations and couldn't fix the problem. (My flash counter sits well over 20 now.)
I got another poster (deeznutz1977) to send me his T889 NV backup (sans IMEI) the other day. I later had the idea of reflashing the I317M modem again, which did not boot loop after all (there may have been a matter of wiping /cache and Dalvik cache at the right time).
This time dialcode *#7284#, selecting "Qualcomm USB Settings" then selecting "RNDIS + DM + MODEM" worked. I could get the programs talking with the phone. I inserted my IMEI in deeznutz1977's backup, wrote that to the phone and rebooted.
The phone doesn't bootloop anymore, my IMEI is back, as is service on my current carrier. One catch is that I am unable to test is if this configuration still works with AWS HSPA. The other is that bootloops resume if I reflash the T889V modem through either CWM or Odin.
I made a few more speed tests before writing this and managed to get an average 45 Mbps down and 12 up along with a 40 ms ping.
Hope that answered a few of your questions.
Regards,
Darkshado
Click to expand...
Click to collapse
Wow... thank you for taking your time and explaining everything... really, thank you... so you managed to completely transform your T889V into a I317M... that's why it now bootloops if flashing the original T889V... as it would if you really had an I317M... is that right?
you don't have access to a sim with the t-mobile band in order to test for just a minute?
So... here is my story... maybe I can help here with the transformation of T889 to I317 and viceversa... (or maybe an hybrid modem like the one for the Note 1)
-> I have both the AT&T I317 and the T-Mobile T889...
-> I also have both with dual sim card adapters...
-> I also have 1 Unlimited everything T-Mobile sim card & 2 AT&T unlimited everything sim cards...
I want to be able to keep the T889 with 1 sim -> working LTE on AT&T and the 2nd sim -> ready for future T-Mobile LTE...both sims in the dual sim card adapter on the same phone of course (I also want to sell the I317) just keep one universal LTE Note 2
What can I do here? Willing to sacrifice whatever I need to... in order to accomplish my objective... This will help everyone here on both carriers...
As for now... I have noted that while navigating on both phones thru the service menu... the I317 says ENS: ENABLED and the T889 says ENS: DISABLED ... searched on google... no answer.... ENS stands for? Emergency Notification System? lol
Is there anything I can do here since I own both phones... that can sort things out in order to unlock the LTE feature on the Tmobile variant? or is that something we all just have to wait for the carrier to do via OTA? Is there any modded modem that can solve this? Your I317M modem... can it do something here for the T889?
On the pictures the one on the left is the I317 and on the right the T889... both with AT&T sims at the moment of the picture. If I go outside, the AT&T Note 2 will get 4G icon (LTE) and the T-Mobile Note 2 will stay in HSPA+...
I have MTP + ADB on both phones when using code *#7284# also... is there anything useful in this code besides unlocking phone? *#197328640# ??? Diagnostic mode here... *#0*# any more codes?

[Q] At&t to T-Mobile prepaid

Here's the issue. I purchased the At&t s3 (SGH-I747) last year. Long story short, I wanted to go to T-Mobile prepaid with the same phone.
I purchased the SIM activation kit for $10, popped my SIM in and it worked!
Before I put the SIM in it though, I paid for an unlock code. I still have the code.
No 'Network Unlock' screen.
No prompt for my unlock code.
I am getting H+ speeds with the at&t s3 on T-Mobile prepaid without doing ANYTHING.
My question is:
Why cant I get to the unlock screen? I have tried to dial "#7465625*638*# for the prompt to popup and NOTHING.
Can someone tell me...
1. Can I flash a T-mobile rom to this phone? (every time i try I get a build.prop error, even after changing the model to the T999 and all that jazz),
so I can't install a T-Mo rom?
2. Do I have to flash a modem/radio or anything else like that?
3. Or, should I just continue to flash At&t Roms with the t-mo prepaid sim?
I have searched for a while now, and noone has my problem. I never expected to just switch sim's and it would work, so ANY help would be appreciated.
Thanks!

bradhoschar said:
Here's the issue. I purchased the At&t s3 (SGH-I747) last year. Long story short, I wanted to go to T-Mobile prepaid with the same phone.
I purchased the SIM activation kit for $10, popped my SIM in and it worked!
Before I put the SIM in it though, I paid for an unlock code. I still have the code.
No 'Network Unlock' screen.
No prompt for my unlock code.
I am getting H+ speeds with the at&t s3 on T-Mobile prepaid without doing ANYTHING.
My question is:
Why cant I get to the unlock screen? I have tried to dial "#7465625*638*# for the prompt to popup and NOTHING.
Can someone tell me...
1. Can I flash a T-mobile rom to this phone? (every time i try I get a build.prop error, even after changing the model to the T999 and all that jazz),
so I can't install a T-Mo rom?
2. Do I have to flash a modem/radio or anything else like that?
3. Or, should I just continue to flash At&t Roms with the t-mo prepaid sim?
I have searched for a while now, and noone has my problem. I never expected to just switch sim's and it would work, so ANY help would be appreciated.
Thanks!
Click to expand...
Click to collapse
in the general section is a thread on converting an i747 att to a t999 tmobile

Hello.
If you have signal then why are you trying to use the code? It is unlocked already!
im not an expert but this is what i know from reading a lot:
1.- I installed a t-mobile (t999) rom modified to work in a att s3 (i747), i think you can flash a any rom from the t999 section (i am not sure about this)
2.- Do NOT try to install a modem from t-mobile or you will hard brick your phone.
3.- Thats a good idea, do it and let me know if it works.
I used this files to convert an i747 to a t999 http://forum.xda-developers.com/showthread.php?t=1771021&page=25 (read from post #246) so now i use customs roms for the t999 i did it because where i live do not have good signal, was stuck at edge and with those files now i have 3g signal.
Btw, i am in the $30 prepaid t mo plan.

Thanks all!
xmanberserker said:
Hello.
If you have signal then why are you trying to use the code? It is unlocked already!
im not an expert but this is what i know from reading a lot:
1.- I installed a t-mobile (t999) rom modified to work in a att s3 (i747), i think you can flash a any rom from the t999 section (i am not sure about this)
2.- Do NOT try to install a modem from t-mobile or you will hard brick your phone.
3.- Thats a good idea, do it and let me know if it works.
I used this files to convert an i747 to a t999 http://forum.xda-developers.com/showthread.php?t=1771021&page=25 (read from post #246) so now i use customs roms for the t999 i did it because where i live do not have good signal, was stuck at edge and with those files now i have 3g signal.
Btw, i am in the $30 prepaid t mo plan.
Click to expand...
Click to collapse
I've been using Att roms with this s3 and with this t-mo sim, Im getting constant H+ speeds here in Pittsburgh.
Thanks to everyone, and I definetely will try the above.
Thanks again, all!:good:

Using t999 on at&t

Well, just moved to washingron, and t-mobile has no coverage within 10 miles of where I am at, but at&t has full 4g here. Got the at&t sim, on the go-phone plan, modified the apn and get data now. However, I keep getting warnings that my sim card is bad by several t-mobile functions. Can I flash an att rom to it, and do I need to avoid the att modems, or are they also ok to flash on the att network?
Sent from my SGH-T999 using xda app-developers app

5ft24 said:
Well, just moved to washingron, and t-mobile has no coverage within 10 miles of where I am at, but at&t has full 4g here. Got the at&t sim, on the go-phone plan, modified the apn and get data now. However, I keep getting warnings that my sim card is bad by several t-mobile functions. Can I flash an att rom to it, and do I need to avoid the att modems, or are they also ok to flash on the att network?
Sent from my SGH-T999 using xda app-developers app
Click to expand...
Click to collapse
No. You can't do that.

re: at&t - tmobile
5ft24 said:
Well, just moved to washingron, and t-mobile has no coverage within 10 miles of where I am at, but at&t has full 4g here. Got the at&t sim, on the go-phone plan, modified the apn and get data now. However, I keep getting warnings that my sim card is bad by several t-mobile functions. Can I flash an att rom to it, and do I need to avoid the att modems, or are they also ok to flash on the att network?
Sent from my SGH-T999 using xda app-developers app
Click to expand...
Click to collapse
First of all, don't flash any modems.
My phone is an AT&T Unlocked i747 Galaxy S3 and I no longer have AT&T service, but instead I chose Tmobile.
I now have a tmobile sim and have been flashing Tmobile roms ever since I changed my carrier to tmobile.
Everything works fine as long as I do NOT flash any Tmobile Modems.
None of the Tmobile or AT&T custom roms contain the modem image.
All of this also holds true when coming from Tmobile sim and going with AT&T sim.
If your phone is not unlocked I would suggest that you unlock it for best results.

Misterjunky said:
First of all, don't flash any modems.
My phone is an AT&T Unlocked i747 Galaxy S3 and I no longer have AT&T service, but instead I chose Tmobile.
I now have a tmobile sim and have been flashing Tmobile roms ever since I changed my carrier to tmobile.
Everything works fine as long as I do NOT flash any Tmobile Modems.
None of the Tmobile or AT&T custom roms contain the modem image.
All of this also holds true when coming from Tmobile sim and going with AT&T sim.
If your phone is not unlocked I would suggest that you unlock it for best results.
Click to expand...
Click to collapse
What about kernels? Which T-Mobile ones can we flash onto an AT&T S3? I'm doing what you are. AT&T S3 on T-Mobile.

re: kernels
popi09 said:
What about kernels? Which T-Mobile ones can we flash onto an AT&T S3? I'm doing what you are. AT&T S3 on T-Mobile.
Click to expand...
Click to collapse
If you have a tmobile sim chip then flash tmobile kernel.
If you have a AT&T sim chip then flash AT&T kernel.
But if I were you I would stay with stock kernels which all the custom Jellybean 4.1.1 roms already come with.
So if you flash a Tmobile custom rom, it will come with a tmobile kernel.
If flashing a AT&T custom rom it will come with the stock AT&T kernel.
Good luck!

Misterjunky said:
If you have a tmobile sim chip then flash tmobile kernel.
If you have a AT&T sim chip then flash AT&T kernel.
But if I were you I would stay with stock kernels which all the custom Jellybean 4.1.1 roms already come with.
So if you flash a Tmobile custom rom, it will come with a tmobile kernel.
If flashing a AT&T custom rom it will come with the stock AT&T kernel.
Good luck!
Click to expand...
Click to collapse
Awesome! I have a T-Mobile Sim in my ATT s3. I'm running universe s4 ROM. So I wouldn't have to flash a kernel when flashing TW ROMs from tmo?

re: kernels
popi09 said:
Awesome! I have a T-Mobile Sim in my ATT s3. I'm running universe s4 ROM. So I wouldn't have to flash a kernel when flashing TW ROMs from tmo?
Click to expand...
Click to collapse
You never have to flash a kernel regardless of which rom you flash.
All roms come with kernels, all the kernels you see here in XDA which are separate
downloads are custom kernels unless they are specified as being stock.
Custom kernels might be OK for experimenting for those people who want to
over clock or under volt their phones. In my opinion it's a waste of time and
cause more problems or issues than whatever advantages they may have.
(in my personal experience custom kernels have no real advantages at all)

tmobile phone att sim cut down
ok i have a unlocked rooted t-mobile phone, a att go phone sim, cut down to size and can make calls , and even send pictures but some small setting is stoping me from geting data to work ,
i have nothing i am worried about backing up so i can install any rom that may work i just need some direction help please i keep reading thru. all the apn setting and cant find what i may be doing wrong

[Q] t-mobile s4 with at&t stock firmware

--------------------------------------------------------------------------------
can I flash a at&t stock firmware with odin to my T-Mobile m919 with out any problems...right now my s4 is sim unlocked and im on at&t network .and it seems like its working ok but signal a little on the low side and spotty lte service....would there be any advantage flashing at&t's stock firmware to use on att network ...would my service and signal be any better.....if I wanted to would I be able to flash back to T-Mobile stock firmware...will it work....anyone try this ..anything I should know before I do this ...thanks in advance

Yes, you can. but be aware that you will lose t mobile features like wifi calling which is really useful.

re: wifi calling
XxKINGxX2580 said:
Yes, you can. but be aware that you will lose t mobile features like wifi calling which is really useful.
Click to expand...
Click to collapse
He will NOT loose Tmobile wifi because he never had it, if he has an AT&T unlocked phone and
odin flashes any tmobile rom there will be no wifi calling because AT&T network itself does not offer it.
The only way he will have Wifi calling would be if he switched from the AT&T network to Tmobile network.
No one will have wifi calling regardless which rom they flash unless they have a tmobile sim card.
hope this clears things up a bit.

Misterjunky said:
He will NOT loose Tmobile wifi because he never had it, if he has an AT&T unlocked phone and
odin flashes any tmobile rom there will be no wifi calling because AT&T network itself does not offer it.
The only way he will have Wifi calling would be if he switched from the AT&T network to Tmobile network.
No one will have wifi calling regardless which rom they flash unless they have a tmobile sim card.
hope this clears things up a bit.
Click to expand...
Click to collapse
I have a T-Mobile phone I use on at&t network ...flashing at&t stock firmware wont lock my phone right ..and should be able to flash back to T-Mobile stock firmware if I wanted to right..wont relock sim or bootloader....thanks guys

re: locked/unlocked
[email protected] said:
I have a T-Mobile phone I use on at&t network ...flashing at&t stock firmware wont lock my phone right ..and should be able to flash back to T-Mobile stock firmware if I wanted to right..wont relock sim or bootloader....thanks guys
Click to expand...
Click to collapse
Nope, it won't lock or re-lock your phone, once a phone is unlocked properly it will stay that way
regardless which rom you flash and regardless if you're on the AT&T network or Tmobile network.
Do not Odin flash the AT&T stock firmware on a Tmobile phone even if it's unlocked.
If you do you will not be able to make or receive any phone calls.
You can flash AT&T or Tmobile CWM/TWRP flashable stock or custom zip file roms because
those do not contain the radio/modem images like the Odin flash firmware do.
If you odin flash back to stock Tmobile firmware you will loose root unless you re-root after flashing.
As far as bootloaders go, a Tmobile phone requires a Tmobile bootloader, but you don't need to worry
about that if you flash the stock official tmobile firmware with Odin.
All the other tmobile and at&t cwm/twrp flashable zip file roms found in these threads don't contain
any bootloaders that's why they can be flashed on any unlocked and rooted tmobile or at&t phones.

Misterjunky said:
Nope, it won't lock or re-lock your phone, once a phone is unlocked properly it will stay that way
regardless which rom you flash and regardless if you're on the AT&T network or Tmobile network.
Do not Odin flash the AT&T stock firmware on a Tmobile phone even if it's unlocked.
If you do you will not be able to make or receive any phone calls.
You can flash AT&T or Tmobile CWM/TWRP flashable stock or custom zip file roms because
those do not contain the radio/modem images like the Odin flash firmware do.
If you odin flash back to stock Tmobile firmware you will loose root unless you re-root after flashing.
As far as bootloaders go, a Tmobile phone requires a Tmobile bootloader, but you don't need to worry
about that if you flash the stock official tmobile firmware with Odin.
All the other tmobile and at&t cwm/twrp flashable zip file roms found in these threads don't contain
any bootloaders that's why they can be flashed on any unlocked and rooted tmobile or at&t phones.
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so the hardware is different is that why you cant flash att stock firmware with odin on a T-Mobile s4

re: locked/unlocked
[email protected] said:
so the hardware is different is that why you cant flash att stock firmware with odin on a T-Mobile s4
Click to expand...
Click to collapse
Exactly, the hardware is only a little different that's why we can use the cwm/twrp flashable zipfile custom
tmobile/at&t roms with either the tmobile locked or unlocked phones or the unlocked at&t phones.
The only exception is that wifi calling only works on an actual tmobile phone with a tmobile
sim card which is on the tmobile network whether it's locked or unlocked.

[email protected] said:
--------------------------------------------------------------------------------
right now my s4 is sim unlocked and im on at&t network
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Click to collapse
Misterjunky said:
The only exception is that wifi calling only works on an actual tmobile phone with a tmobile
sim card which is on the tmobile network whether it's locked or unlocked.
Click to expand...
Click to collapse
Don't think it matters if WiFi calling isn't enabled.

I thought the hardware between the AT&T s4 and the T Mobile s4 was the same. I thought the reason they received different radio frequencies was in the firmware and not the hardware can anyone confirm ..
I wanted to try to flash AT&T stock firmware on my t-mobile s4 for better performance on AT&T network

[email protected] said:
I thought the hardware between the AT&T s4 and the T Mobile s4 was the same. I thought the reason they received different radio frequencies was in the firmware and not the hardware can anyone confirm ..
I wanted to try to flash AT&T stock firmware on my t-mobile s4 for better performance on AT&T network
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Click to collapse
I would love the answer to this question too.

The key is the Modem aka Baseband. This is the Radio file and it is hardware and carrier dependent. If you try to flash this you will mess up the bootloader and radio and you have a brick.

I'm too on AT&T network with T-Mobile phone. I'm using the stock MDL radio and it's working fine. I don't notice a difference between the 2 devices on LTE network. if T-Mobile can't lock on to LTE network, AT&T S4 won't either.

sorry to slightly threadjack.... but does that mean if i flash a custom s4 AT&T rom (i.e. "CleanRom"), i will still be going through a Tmobile bootloader \ kernal etc..?
Is there any foolproof way to "convert" an tmobile s4 to an ATT based s4?

Can't you guys just flash a popular custom rom for sgh-i337 variant and then change the radioband (or whatever it's called) sh*t manually? If you ever flash another carrier rom, make sure ur baseband is the original carrier/phone as stated before. And flash ur carrier/phone kernel(custom or stock, doesn't matter) as well.

I believe these ppl created this topic because they want the stock carrier branded firmware on their phone, so that they can have all the carrier specific features on their phone. Third party ROM is not their choice, otherwise there are tones post out there already. I believe someone must be brave enough to flash it to their phone to test that, otherwise, there is no good answer to that.

Cal-El said:
The key is the Modem aka Baseband. This is the Radio file and it is hardware and carrier dependent. If you try to flash this you will mess up the bootloader and radio and you have a brick.
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Hi guys, anyone can tell me if this will work:
I have TMO M991 and I want to use it in Europe but have problem with network signal (not registered on network; missed calls & s... like that).
My guess is that radio is different and optimized for LTE, which we dont have here...
I m thinking of flashing I9505 stock rom and baseband...what do You think, will this improve radio reception/stable network signal?
I9505 is the version used in Europe region...
I honestly tried to find similar topics, no luck so far so pls point me in the right direction if nothing else...
Cheers!

Unlocked an At&t SGS3 for use on Tmo

Hey guy I just unlocked an old SGS3 for AT&T SGH-I747. Now i plan on giving the phone to my mom for her to use since her current phone is a POS... how would i go about getting tmobile firmware on it for her without bricking. I know i have to root first and then Recovery then Rom, but is it safe and stable to run TMO rom on the att model of the S3. I just want to make sure that i go about this the rite way.
Thanks in advance

Will she be using T-Mobile data? The i747 does not natively support aws frequencies so that may be a problem. Voice calls would probably work.
You can't flash the t999 modem and bootloader to the i747 so forget about flashing a T-Mobile rom to i747.

Pray tell: How did you Un-Lock it?
I haven't been able to get past the debug screen?
Any info is appreciated, Thanks!
JosephJ85 said:
Hey guy I just unlocked an old SGS3 for AT&T SGH-I747. Now i plan on giving the phone to my mom for her to use since her current phone is a POS... how would i go about getting tmobile firmware on it for her without bricking. I know i have to root first and then Recovery then Rom, but is it safe and stable to run TMO rom on the att model of the S3. I just want to make sure that i go about this the rite way.
Thanks in advance
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Click to collapse