[Q] Much needed unlock method for Galaxy S3 running 4.3 - AT&T, Rogers, Bell, Telus Samsung Galaxy S III

Hey guys, not trying to make the 100th thread this week asking for this, but I've looked through all of them without any close answers. I'm in need of a solution to unlock my AT&T Samsung Galaxy S3 SGH-I747 phone on 4.3 firmware to be able to use a T-Mobile SIM card.
It was unlocked before running 4.4.2 on Quantum ROM and I decided to fresh clean the phone to start new. I so happened to soft-bricked my phone accidentally, but brought it back now to 4.3. Now under baseband version and IMEI it says UNKNOWN.
1) I read that it is possible to downgrade to 4.1.1 without downgrading the bootloader using ODIN. I have no ideas on what ROM to use, and what program to downgrade with since I can't use ODIN.
2) I read that you can call AT&T and request an unlock code. For this to work, do I need to be an AT&T customer? I'm currently using T-Mobile.
Any solutions?

Try and fix your imei/baseband problem first.
Maybe this will help: http://forum.xda-developers.com/showthread.php?t=1804117

audit13 said:
Try and fix your imei/baseband problem first.
Maybe this will help: http://forum.xda-developers.com/showthread.php?t=1804117
Click to expand...
Click to collapse
Thanks! I'm in the middle of trying to restore my IMEI, however when I dial the number for the service mode, I only have two options under UART: PDA and MODEM. I'm not able to select MODEM either.

JohnnyCrawl said:
Thanks! I'm in the middle of trying to restore my IMEI, however when I dial the number for the service mode, I only have two options under UART: PDA and MODEM. I'm not able to select MODEM either.
Click to expand...
Click to collapse
DO you have a custom recovery installed? Maybe install a custom ROM and see if you have those options available?
Your imei and baseband may be missing because you don't have a modem image installed.

audit13 said:
DO you have a custom recovery installed? Maybe install a custom ROM and see if you have those options available?
Your imei and baseband may be missing because you don't have a modem image installed.
Click to expand...
Click to collapse
No I don't believe I installed a modem. I used Looserskaters S3Rx ROM from the "[HOW TO GUIDE] How To Unbrick AT&T I747 and I747M After 4.3 OTA" thread. The rom is located here: http://forum.xda-developers.com/showthread.php?t=2252932
I don't know which modem to use. There's a MJ2 and MJB one.

Try either one. I believe the MJB is the most recent. Flashing a modem doesn't affect the bootloader.

audit13 said:
Try either one. I believe the MJB is the most recent. Flashing a modem doesn't affect the bootloader.
Click to expand...
Click to collapse
That was it! Thanks for the help. Safe to say I'm able to update to 4.4.2 using the Quantum ROM?

JohnnyCrawl said:
That was it! Thanks for the help. Safe to say I'm able to update to 4.4.2 using the Quantum ROM?
Click to expand...
Click to collapse
Just make sure you're running the latest version of your recovery. I prefer Philz Touch as I had some troubles using TWRP.

So I was sondering how to unlock if you are on stock mjb... Do the sketchy downgrade to 4.1.1 then use the dial unlock?

JohnnyCrawl said:
Thanks! I'm in the middle of trying to restore my IMEI, however when I dial the number for the service mode, I only have two options under UART: PDA and MODEM. I'm not able to select MODEM either.
Click to expand...
Click to collapse
instead of using the code *#7284#.. try *#0808#
and once you're on 4.3 bootloader, you can't use free unlock
so buy unlock code or trick AT&T for one somehow

blu422 said:
So I was sondering how to unlock if you are on stock mjb... Do the sketchy downgrade to 4.1.1 then use the dial unlock?
Click to expand...
Click to collapse
If you have the mjb bootloader, do not attempt to downgrade the bootloader as it may brick your phone. You will have to buy an unlock code as there is no free method available at the moment.

unlock
pcshano said:
instead of using the code *#7284#.. try *#0808#
and once you're on 4.3 bootloader, you can't use free unlock
so buy unlock code or trick AT&T for one somehow
Click to expand...
Click to collapse
i have a 4.3 bootloader and been given a unlock code by telus
now whats next
*#197328640# does not work

Because you're on aosp.. go back to touchwiz
Sent from my SAMSUNG-SGH-I747 using Tapatalk

audit13 said:
If you have the mjb bootloader, do not attempt to downgrade the bootloader as it may brick your phone. You will have to buy an unlock code as there is no free method available at the moment.
Click to expand...
Click to collapse
im talking about the method to downgrade w/o ovrwriting the bl

blu422 said:
im talking about the method to downgrade w/o ovrwriting the bl
Click to expand...
Click to collapse
You can downgrade the ROM and leave the bootloader untouched but this will not allow you to unlock the phone using the free method. You need to be running the 4.1.1 bootloader with the 4.1.1 stock ROM.

just the modem
will that work can anybody explain how to do it?

What bootloader is on your phone? If you have 4.3 or higher, flashing just the modem won't work to use the free method. If you have a 4.4 bootloader, mixing modems could brick the phone.

Related

[Q] Network unlock request unsuccessful (SGH-I747M - Running SlimKat 4.4.4)

Just purchased an unlock code from Telus but it does not work. I know some posts mentioned it only works with a stock dialer app.
Is there anything else I can try before attempting that?
If not, what stock rom can I even use? And is there a guide available?
Sorry if this has been asked before. I had trouble finding any answers.
Thank you.
Just flash your stock firmware with Odin.
The boot loader on your phone will determine which firmware to load on your phone.
If you have the 4.3 bootloader, don't flash 4.1.1 or 4.1.2.
Flashed stock rom, booted with sim inserted, and entered the unlock code when asked. It worked! Thanks for the reassurance, I was hesitant.
Here are some links I came across that might help others.
Downloaded latest ROM for my carrier: http://samsung-updates.com/device/?id=SGH-I747m
Got Odin from this post: http://forum.xda-developers.com/showthread.php?t=1722686
Followed these threads to flash with Odin:
http://forum.xda-developers.com/galaxy-s3/help/guide-odin-flash-guide-t1671969
http://forum.xda-developers.com/showthread.php?t=2789917
http://forum.xda-developers.com/showthread.php?t=1722686
Read the CyanogenMod guide to install SlimKat: http://wiki.cyanogenmod.org/w/Install_CM_for_d2att
SlimKat XDA thread: http://forum.xda-developers.com/showthread.php?t=2758209
Root: http://slimroms.net/index.php/faq/slimbean/441-how-do-i-enable-root
Downloaded Texdroider DPI from the play store to change to S3 default (320)
Then I thanked everyone I could! :victory:
Notes
* I forgot to wipe my device before and it still worked.
* TWRP would not read my SD card for some reason.
* Good info threads:
http://forum.xda-developers.com/showthread.php?t=1725839
http://forum.xda-developers.com/showthread.php?t=1802160
Glad to hear you got it to work! Couple things for extra knowledge. ..
You can also get firmware from http://sammobile.com/firmwares. Their downloads are much faster than samsung-updates IME.
Easiest root method ever! - Towelroot (shouldn't trip the warranty bit either)
If I'm not mistaken, the recoveries having problems reading the sd card is due to your hardware version. I believe they found a solution in the Sprint forums, but I haven't had a chance to read up on it yet. If its something I can do I'll probably try to fix the T-Mobile and AT&T recoveries. I may be mistaken on some of that, but its how I understood it after a quick search the other day.
Need help for flashing stock rom
Hi,
Can you please clarify few things for me?
I have an ATT Galaxy S3 (SGH-i747).
I am running CM11 Android 4.4.4 Baseband I747UCDMG2.
I need to go back to stock to SIM unlock the phone.
Latest ATT stock rom is 4.1.1 with I747UCDLK3.
Will flashing to stock ATT ROM brick the phone?
What is the best way to go back to stock ROM?
Thanks,
I have an ATT Galaxy S3 (SGH-i747).
Click to expand...
Click to collapse
My phone was the same; except being the Canadian version.
I am running CM11 Android 4.4.4 Baseband I747UCDMG2.
Click to expand...
Click to collapse
I think I had CM 4.4.4 before going back to stock. It was kitkat for sure tho.
Will flashing to stock ATT ROM brick the phone?
Click to expand...
Click to collapse
It shouldn't. But of course anything can happen.
What is the best way to go back to stock ROM?
Click to expand...
Click to collapse
Using ODIN I believe. I read through all the links I posted above but I guess this one was the easiest to follow.
http://forum.xda-developers.com/galaxy-s3/help/guide-odin-flash-guide-t1671969
Hope that helps, it has been a while lol. Maybe someone with more experience will chime in :good:
brando9 said:
My phone was the same; except being the Canadian version.
I think I had CM 4.4.4 before going back to stock. It was kitkat for sure tho.
It shouldn't. But of course anything can happen.
Using ODIN I believe. I read through all the links I posted above but I guess this one was the easiest to follow.
http://forum.xda-developers.com/galaxy-s3/help/guide-odin-flash-guide-t1671969
Hope that helps, it has been a while lol. Maybe someone with more experience will chime in :good:
Click to expand...
Click to collapse
Thanks for quick reply.
Bootloader on mine is I747UCDMG2 which is from 4.1.2. Hence I should be ok to go to stock 4.1.1 ROM.
I am reading few other posts before making the move.
Flashing the USA version of the s3 (i747) with any i747 firmware from sammobile in Odin can brick your phone us you have a 4.3 bootloader or higher.
Since you are on 4.1.2 bootloader, flash the stock ATT 4.1.1 ROM from sammobile.com using Odin. After flashing, do a full wipe in recovery. Boot the phone and use the free method to permanently sim unlock your phone.
After unlocking your phone, you can run OTA updates to get to the latest stock ROM, bootloader, and modem.
Just confirmed bootloader and baseband are I747UCDMG2.
I will update here how everthing goes.
PS: I DON'T want to go to I747UCUEMJB bootloader after unlock. That will mean, I will not be able to downgrade in future. AFAIK, I747UCUEMJB bootloader is also locked.
yoonus said:
Just confirmed bootloader and baseband are I747UCDMG2.
I will update here how everthing goes.
PS: I DON'T want to go to I747UCUEMJB bootloader after unlock. That will mean, I will not be able to downgrade in future. AFAIK, I747UCUEMJB bootloader is also locked.
Click to expand...
Click to collapse
correct in that you will not be able to downgrade (serious risk of bricking your device).
bootloader is not locked on the S3 AFAIK. (bricked my s3 on mj2 trying to 'unlock' an already unlocked bootloader.).
"all i can really do , is stay out of my own way and let the will of heaven be done"
mrrocketdog said:
correct in that you will not be able to downgrade (serious risk of bricking your device).
bootloader is not locked on the S3 AFAIK. (bricked my s3 on mj2 trying to 'unlock' an already unlocked bootloader.).
"all i can really do , is stay out of my own way and let the will of heaven be done"
Click to expand...
Click to collapse
I agree that the bootloader is unlocked.
I think at times people are calling the newer bootloaders locked because they are unable to downgrade them. Whereas we are calling them unlocked because we can still root them and flash custom/unsigned ROMs.
ATT has been locking the bootloader on other phones such as the Note 3, HTC One XL, and the Moto G so I'm not surprised that owners think their bootloader is locked.
audit13 said:
ATT has been locking the bootloader on other phones such as the Note 3, HTC One XL, and the Moto G so I'm not surprised that owners think their bootloader is locked.
Click to expand...
Click to collapse
True. I have an ATT S5 and is really annoyed with locked bootloader.
flash to stock successful
yoonus said:
Just confirmed bootloader and baseband are I747UCDMG2.
I will update here how everthing goes.
PS: I DON'T want to go to I747UCUEMJB bootloader after unlock. That will mean, I will not be able to downgrade in future. AFAIK, I747UCUEMJB bootloader is also locked.
Click to expand...
Click to collapse
Thanks all for the assurance and support.
I was able to ODIN to stock ROM and SIM unlock the phone.
Background: My ATT S3 i747 was running CM11 Android 4.4.4. Baseband and Bootloader was I747UCDMG2.
Steps:
1. Flashed rooted stock ROM (root66_ATT_I747UCDLK3.7z) using odin from http://forum.xda-developers.com/showthread.php?t=1739426
Followed the steps in OP.
After flash ODIN showed PASS and phone rebooted. It was stuck in Samsung logo. I booted into recovery. Performed a wipe cache and factory restore.
Phone rebooted successfully after that.
2. Inserted non-ATT SIM and it asked for the unlock code. I had obtained the code from ATT before. Used the code and phone was unlocked.
The same code did not work while I was running CM11.
NOTE: When running stock ROM you can follow steps in below threads if direct unlock did not work for you.
1. http://forum.xda-developers.com/showpost.php?p=58671214&postcount=152
2. http://forum.xda-developers.com/showthread.php?p=38767845#post38767845 This works only with stock 4.1.1 image (LK3 modem).
See http://forum.xda-developers.com/showpost.php?p=59029460&postcount=323
NOTE: If you need TWRP recovery, see http://forum.xda-developers.com/showthread.php?t=1739426 and search for "Odin Flashable TWRP Recovery" in OP.
You can download ODIN flashable TWRP from there.

Sim Unlock Rogers S3 on CM11 M10 (4.4.4) [SOLVED]

Hi everyone,
I am looking for a way to sim unlock my S3 so my girlfriend can use it on Telus (I just got an OPO )
Before I purchase a code, I have a few questions, if anyone knows the answer
1- Will an unlock code work with my setup? (I am seeing reports of it only working on Stock 4.1 and whatnot)
2- Where is a good place to purchase a code? (Rogers a crooks with a 50$ fee and I don't wanna get ripped off online either)
Thanks!
XC3N
You will need to be running a stock or close to stock ROM in order to use the unlock code. You do not need to be on stock 4.1.1 to use an unlock code. You need to be running stock 4.1.1 if you want to unlock using the free method. You may be able to unlock it using a code if you are running a stock dialler.
What bootloader or baseband is on your phone?
audit13 said:
You will need to be running a stock or close to stock ROM in order to use the unlock code. You do not need to be on stock 4.1.1 to use an unlock code. You need to be running stock 4.1.1 if you want to unlock using the free method. You may be able to unlock it using a code if you are running a stock dialler.
What bootloader or baseband is on your phone?
Click to expand...
Click to collapse
I managed to get a code from Rogers for half the price, which is "not that bad" I guess...
I have yet to try it as I don't have the SIM card with me atm.
Baseband: I747MVLUEMK5
it's my understanding that downgrading from this will brick your phone...
Thanks for all the info!
Yes, trying to downgrade from mk5 will brick your phone.
Find the stock Rogers ROM from sammobile.com and flash it via Odin. Flashing back to stock will wipe all user data and files so make sure you backup everything you need before flashing back to stock.
audit13 said:
Yes, trying to downgrade from mk5 will brick your phone.
Find the stock Rogers ROM from sammobile.com and flash it via Odin. Flashing back to stock will wipe all user data and files so make sure you backup everything you need before flashing back to stock.
Click to expand...
Click to collapse
Ok I tried the code and it didn't work.
I'll read up on the Odin procedure... I've done it before on another phone but I wanna make sure I don't end up with a brick! Thanks!
Sent from my A0001 using XDA Free mobile app
ah one more thing... since I'm using the unlock code (I don't believe the free method works on Rogers phone anyway) should I flash to stock MK5?
If I go to stock MK5, eill I be able to come back to CM afterwise?
Thanks!
The free method will only work if you are running an i747 or i747m on stock 4.1.1 including the bootloader.
If you flash back to stock mk5, you should be able to re-install cwm and CM11. There are many threads on disabling knox and install CWM.
audit13 said:
The free method will only work if you are running an i747 or i747m on stock 4.1.1 including the bootloader.
If you flash back to stock mk5, you should be able to re-install cwm and CM11. There are many threads on disabling knox and install CWM.
Click to expand...
Click to collapse
Hi! Reporting back, everything worked well flashing stock rom using this method:
http://forum.xda-developers.com/showthread.php?t=1739426
I had a slight problem after the Odin flash where I had to boot to recovery and factory reset to get out of a boot loop, but everything went fine after that.
I managed to unlocked the phone, changed the recovery using the aforementioned thread and got back up and running on CM11 M10 in no time!
Thanks a lot for your help sir =)
Francis // XC3N

[Q] My AT&T S3 is Bricked, HELP!

I updated to Cyanogenmod 11's latest nightly of 4/26/2015 and my phone started behaving badly.
I kept losing signal and having trouble making calls and in my attempts to resolve the issue by flashing back to a previous nightly it seems I lost my IMEI and with it connectivity.
I found a video on youtube that says to access the service menu to fix it but CyanogenMod doesn't do anything when I enter the codes in the dialer so I was attempting tro go back to stock but having trouble finding a good stock rom I can use and the 2 I"ve tried both fail in odin. Then I read something about needed a pit file but flashing that fails to.
So right now I went back stop recovery but still on Cyanogenmod but the phone doesn't do anything when it boots...just no connection.
Someone told me the pros in this forum could help so here I am, help me Cell Phone Gods!!!:crying:
Got this phone info app that says bootloader is I747UCUEMJB
Update 5/5/2015 I'm on latest bootloader and running stock rom but have no data and both calling and text work randomly. 4G symbol comes on once in a while but most of the service I do get when it works is on edge network.
Sounds like your modem may be messed up.
Load a terminal app and use the app to verify the bootloader on your phone.
audit13 said:
Sounds like your modem may be messed up.
Load a terminal app and use the app to verify the bootloader on your phone.
Click to expand...
Click to collapse
how do I do that? with my pc? what's a good app to use?
Try this: boot into download and read the screen. Do you see anything about warranty bit on the phone?
audit13 said:
Try this: boot into download and read the screen. Do you see anything about warranty bit on the phone?
Click to expand...
Click to collapse
Yes, says Warranty bit 1
system status official.
What's that tell you?
btw i just went back to CWM
got this phone info app that says bootloader is I747UCUEMJB
Odin is failing with the stock ROM from sammobile because the phone has at least a 4.3 bootloader on your phone. Do not flash anything from sammobile because attempting to do so could brick your phone.
Since you're back on cwm with an mjb bootloader, try flashing the mjb modem via cwm.
http://forum.xda-developers.com/showpost.php?p=47817339&postcount=23
audit13 said:
Odin is failing with the stock ROM from sammobile because the phone has at least a 4.3 bootloader on your phone. Do not flash anything from sammobile because attempting to do so could brick your phone.
Since you're back on cwm with an mjb bootloader, try flashing the mjb modem via cwm.
http://forum.xda-developers.com/showpost.php?p=47817339&postcount=23
Click to expand...
Click to collapse
I tried flashing the modem before...I'll do it again...is that going to get me my IMEI number back or allow me to flash stock rom to recover my IMEI?
fausto412 said:
I tried flashing the modem before...I'll do it again...is that going to get me my IMEI number back or allow me to flash stock rom to recover my IMEI?
Click to expand...
Click to collapse
I did flash the modem you linked and that improved things a bit...I'm back to the original problem, I was having where my phone was having trouble staying on the network. I had even lost all my APNs in my attempts to fix. Now my APNs are back. Still showing unkown IMEI and phone isn't getting on the cell phone network.
So the baseband is now mjb?
Try flashing the latest release of CM10.2. It's possible you need to update the modem and bootloader together in order to support the newest release of CM11. I don't have an s3 so i can't confirm my theory.
You may have to try nvwriter to inject the imei as a last resort: http://forum.xda-developers.com/showthread.php?t=1804117
audit13 said:
So the baseband is now mjb?
Try flashing the latest release of CM10.2. It's possible you need to update the modem and bootloader together in order to support the newest release of CM11. I don't have an s3 so i can't confirm my theory.
You may have to try nvwriter to inject the imei as a last resort: http://forum.xda-developers.com/showthread.php?t=1804117
Click to expand...
Click to collapse
Yes baseband is MJB.
I'll install 10.2 real quick. In the past that didn't help but who knows this time.
OK. Installed 10.2.1 and still have null imei. Connects to cell networks unreliably but no data and texting.
Sent from my SAMSUNG-SGH-I747 using XDA Free mobile app
fausto412 said:
OK. Installed 10.2.1 and still have null imei. Connects to cell networks unreliably but no data and texting.
Sent from my SAMSUNG-SGH-I747 using XDA Free mobile app
Click to expand...
Click to collapse
not as smart as @audit13 , but might find some help here. good luck.
http://forum.xda-developers.com/showthread.php?t=1804117
"all i can really do , is stay out of my own way and let the will of heaven be done"
Did you confirm that your modem and bootloader match? Did you try nvwriter to inject the imei?
I believe modem and bootloader match. Haven't tried nvwriter...can't access service mode on cyanogen apparently.
What do I do now?
Sent from my SAMSUNG-SGH-I747 using XDA Free mobile app
audit13 said:
Did you confirm that your modem and bootloader match? Did you try nvwriter to inject the imei?
Click to expand...
Click to collapse
The NV Writer method, I get stuck at this point in the instructions
"*If you are running a aosp rom (cm9,cm10,aokp etc) you can use the diag method described HERE"
The link is dead so I've no idea what I'm supposed to do.
Since your imei is null, I'm not sure what else to suggest except to re-flash the existing bootloader and modem or flash a newer bootloader and modem.
audit13 said:
Since your imei is null, I'm not sure what else to suggest except to re-flash the existing bootloader and modem or flash a newer bootloader and modem.
Click to expand...
Click to collapse
There is a newer bootloader and modem?
I sure wish I had an easier time with finding out this info plus the files.
http://forum.xda-developers.com/galaxy-s3-att/general/modem-4-4-2-modems-i747-i747m-t2856577
OK, about to try to update to ne4 bootloader and modem. wish me luck!
Updated to NE4 firmware but modem file failed due to being on NE4 firmware(wth!)...obtained a different file that installed ok.
Result...still having null IMEI and no LTE...inconsistent connection issues.
I wonder if I was on NJ1 before I started messing around....

Modem requirements for lollipop?

I am trying to upgrade an S3 from an older kit kat aosp rom to a 5.0+ rom. The phone is still on the UCDMG2 bootloader/baseband combo. I kept it on that version to keep my unlocked bootloader and not worry about all this e-fuse stuff going on.
So here is the problem. 5.0 roms flash ok, but say I have no signal. I am able to make phone calls and send text messages, but I have no data. Is there a modem I can flash that will work on 5.0+ roms with the old bootloader? I have been sifting through the various modem/bootloader threads with no luck. Any suggestions on how to obtain data?
condor97 said:
I am trying to upgrade an S3 from an older kit kat aosp rom to a 5.0+ rom. The phone is still on the UCDMG2 bootloader/baseband combo. I kept it on that version to keep my unlocked bootloader and not worry about all this e-fuse stuff going on.
So here is the problem. 5.0 roms flash ok, but say I have no signal. I am able to make phone calls and send text messages, but I have no data. Is there a modem I can flash that will work on 5.0+ roms with the old bootloader? I have been sifting through the various modem/bootloader threads with no luck. Any suggestions on how to obtain data?
Click to expand...
Click to collapse
as i understand it , and could be completely wrong , but bootloaders and modems should always match. have you tried a different kernel ?
http://forum.xda-developers.com/showthread.php?t=2390147
quantum was an excellent kernel when i had my S3. also i believe ktoonsez makes a lollipop kernel but i couldnt find the link.
as always , backupbackupbackup and readreadread.
"all i can really do , is stay out of my own way and let the will of heaven be done"
mrrocketdog said:
as i understand it , and could be completely wrong , but bootloaders and modems should always match. have you tried a different kernel ?
http://forum.xda-developers.com/showthread.php?t=2390147
quantum was an excellent kernel when i had my S3. also i believe ktoonsez makes a lollipop kernel but i couldnt find the link.
as always , backupbackupbackup and readreadread.
"all i can really do , is stay out of my own way and let the will of heaven be done"
Click to expand...
Click to collapse
Thank you. I have not tried a kernel. Do you think that would help with connectivity?
I was wondering about the boot loader thing. Perhaps there is no way to avoid the upgrade.
Sent from my SAMSUNG-SGH-I747 using XDA Premium 4 mobile app
The bootloaders on the i747 and i747m are not locked.
audit13 said:
The bootloaders on the i747 and i747m are not locked.
Click to expand...
Click to collapse
Ok good to know. So once you upgrade, you don't have to unlock the bootloader to flash recovery/rom?
Edit: sorry, dumb question.
After upgrading to the mjb or newer bootloader, you cannot downgrade the bootloader to an older version. Also, the upgraded bootloader will remain unlocked so you can easily flash a custom recovery in Odin.
audit13 said:
After upgrading to the mjb or newer bootloader, you cannot downgrade the bootloader to an older version. Also, the upgraded bootloader will remain unlocked so you can easily flash a custom recovery in Odin.
Click to expand...
Click to collapse
Can you point me towards the best way to upgrade? I have found some flashable zips, but would prefer to do it through Odin.
I think the safest way to get to the newest bootloader and modem would be to use the 4.1.1 firmware on sammobile.com to flash back to stock in Odin. Once you set up the ROM on your phone, run the OTA updates until you have the latest modem and bootloader. It the slowest way to do but, in my opinion, the safest.
If you phone is not sim unlocked, you can use the free method to permanently unlock the phone while you are on stock 4.1.1.
Once you are on the latest ROM, you could install a custom recovery, create a nandroid backup of the stock ROM, and then flash a custom ROM.
audit13 said:
I think the safest way to get to the newest bootloader and modem would be to use the 4.1.1 firmware on sammobile.com to flash back to stock in Odin. Once you set up the ROM on your phone, run the OTA updates until you have the latest modem and bootloader. It the slowest way to do but, in my opinion, the safest.
Once you are on the latest ROM, you could install a custom recovery, create a nandroid backup of the stock ROM, and then flash a custom ROM.
Click to expand...
Click to collapse
Ok thanks!
condor97 said:
Ok thanks!
Click to expand...
Click to collapse
Is the phone sim unlocked?
audit13 said:
Is the phone sim unlocked?
Click to expand...
Click to collapse
No, it is not. I don't think Lol.
Sent from my SAMSUNG-SGH-I747 using XDA Premium 4 mobile app
You should run through the free unlock method after you flash back to stock. Even if the phone is already unlocked, it won't re lock.
audit13 said:
You should run through the free unlock method after you flash back to stock. Even if the phone is already unlocked, it won't re lock.
Click to expand...
Click to collapse
That is a good idea. Thanks!

Can i Downgrade my AT&T running stock 4.4.2 rom to 4.1.1 ?

Can i downgrade urooted I747 from 4.4.2 to 4.1.1 using odin without bricking my phone?
My build number is KOT49H.I747UCUFNJ1
And also can i update that to 4.4.2 OTA again?
Please reply soon.
You can downgrade the ROM but not the bootloader. Attempts to downgrade the bootloader will probably brick the phone.
audit13 said:
You can downgrade the ROM but not the bootloader. Attempts to downgrade the bootloader will probably brick the phone.
Click to expand...
Click to collapse
Im sort for noob question. But whats a bootloader and how can I downgrade to 4.1.1 without flashing bootloader?
Are you trying to downgrade to 4.1.1 to sim unlock the phone using the free method? If you are, this will not work because the 4.1.1 modem will not work on a 4.4.2 bootloader. You will need to obtain an unlock code.
audit13 said:
Are you trying to downgrade to 4.1.1 to sim unlock the phone using the free method? If you are, this will not work because the 4.1.1 modem will not work on a 4.4.2 bootloader. You will need to obtain an unlock code.
Click to expand...
Click to collapse
MY phone is already sim unlocked I am just trying to fresh install stock Rom on my phone which is on 4.4.2. Can you help me with links please. AND THANKS for the quick reply
You will not be able to downgrade the rom to 4.1.1 while keeping the bootloader at 4.4.2 because the modem will not work on a 4.4.2 bootloader which means you probably can't run ota updates.
To downgrade without touching the bootloader and modem, you need to use mobile Odin. Also, you will have to find a source for the 4.1.1 stock rom since att pulled it from sammobile.com.
audit13 said:
You will not be able to downgrade the rom to 4.1.1 while keeping the bootloader at 4.4.2 because the modem will not work on a 4.4.2 bootloader which means you probably can't run ota updates.
To downgrade without touching the bootloader and modem, you need to use mobile Odin. Also, you will have to find a source for the 4.1.1 stock rom since att pulled it from sammobile.com.
Click to expand...
Click to collapse
Willl this work If i flash with mobile odin?
sammobile,com/firmwares/database/SGH-I747/
You may be able to flash 4.1.1 with mobile Odin but ota updates probably won't work due to a mismatch between the bootloader and rom. Also, the ota updates normally get applied in order: first, 4.3, then 4.4.2.
So in Theory If we flashed back and was a success...
Then we can do the unlock and flash back to 4.2.2 then rom it again ?
stunna946 said:
So in Theory If we flashed back and was a success...
Then we can do the unlock and flash back to 4.2.2 then rom it again ?
Click to expand...
Click to collapse
i am still not certain. But thanks for your time and effort )
stunna946 said:
So in Theory If we flashed back and was a success...
Then we can do the unlock and flash back to 4.2.2 then rom it again ?
Click to expand...
Click to collapse
Nope, can't unlock using the free method if the phone is running a 4.3 or newer bootloader. Even if you downgrade the rom to 4.1.1.
audit13 said:
Nope, can't unlock using the free method if the phone is running a 4.3 or newer bootloader. Even if you downgrade the rom to 4.1.1.
Click to expand...
Click to collapse
Thanks, Ive tried going thru ATT to unlock phones in the past its like pulling teeth. I have a 0 success rate. :crying: I Just have this Brand new T mobile sim I want to use.
Furthermore, I've even tried the I'm going over seas trick.. They say they will send it to my email, an nothing; Ive even called back to confirm the correct email too..
stunna946 said:
Thanks, Ive tried going thru ATT to unlock phones in the past its like pulling teeth. I have a 0 success rate. :crying: I Just have this Brand new T mobile sim I want to use.
Furthermore, I've even tried the I'm going over seas trick.. They say they will send it to my email, an nothing; Ive even called back to confirm the correct email too..
Click to expand...
Click to collapse
Any chance their emails are ending up in a spam/advertising folder and not making it to your inbox?
I've had no problems with AT&T unlocking phones in past. As long as you're "eligible" (I assume that means off contract) they email the codes and instructions, no fuss.

Categories

Resources