[Q] how to unlock galaxy s4 from straighttalk SM-S975L

[lilmul123]

Just out of curiosity, if the hardware is actually the AT&T variant (signified by the SGHI337 in the FCCID), why would the T-mobile TWRP work and not the AT&T TWRP? Or the AT&T ROM for that matter? Seems strange.

 

[aromerblz]

Just out of curiosity, if the hardware is actually the AT&T variant (signified by the SGHI337 in the FCCID), why would the T-mobile TWRP work and not the AT&T TWRP? Or the AT&T ROM for that matter? Seems strange.

That is what i find strange on this phone. As I go along experimenting with this phone am sure I might find something to explain that. But at the moment that's one question lingering on my mind.

 

[carlyman]

I'm not that familiar with Android Kitchen....any reason you couldn't flash TWRP, then flash the T-Mobile ROM, S975L baseband, and kernel all separately (versus creating a custom ROM)? Also...did you have issues with 4.4.4 (curious on why you selected 4.4.2)?

-JC

 

[lilmul123]

This is going to be my first custom ROM experience in about two years (I switched to iPhone in 2012 from a Droid Incredible), so I also have some similar questions.

I've gleaned that TWRP *must* be flashed separately because there will be no way to install the ROM without it. After that, I'm mostly at a loss. Is there a good tutorial somewhere that I could use to build my own ROM that will work? I also have the same question about 4.4.4. I'm assuming it's because aromerblz hasn't done this in a while.

 

[aromerblz]

Am creating a guide for me to post over here. to answer a few of the questions. When i flash the AT&T TWRP recovery which should technically be accepted by the phone since its an identical version of the SGH-I337, the phone does not boot to recovery at all. Am downloading other versions to try out tonight and report if i can successfully flash one and load the AT&T Rom I made with the kitchen. By the way the ROM is pure stock as its made from the official Samsung Odin flash-able file. On the other hand the jfltetmo recovery works fine to flash the TMO Rom that I also created, but when I try with the AT&T Rom it flashes but erases the system partition and thus leaving your phone with no OS on it. Am trying to understand why it does that and still working to fix. Now the reason why I flashed the 4.4.2 and not the latest 4.4.4 dated 11/17/14 is because the sim unlock does not work as compare to the 4.4.2 rom. Meaning as I had mentioned before that a friend was able to get me the unlock code but i need to enter it every time I turn on the phone. Annoying but the phone works perfect with no data or call issues that i have encountered. So for me to use the phone with my local carrier i cannot update to 4.4.4. Since you guys aren't planning to unlock the phone, it should work just fine on 4.4.4 for you.

Here is the link to use dsixda's Android Kitchen: http://xdaforums.com/showthread.php?t=633246

---------- Post added at 05:57 PM ---------- Previous post was at 05:53 PM ----------

I'm not that familiar with Android Kitchen....any reason you couldn't flash TWRP, then flash the T-Mobile ROM, S975L baseband, and kernel all separately (versus creating a custom ROM)? Also...did you have issues with 4.4.4 (curious on why you selected 4.4.2)?

-JC

The Kernel can be included in the rom zip. just replace the stock boot.img, I chose to flash separately since i was already used to do so with my retired HTC One X

also if any WiFi issues are found then do this:
"To make wifi work when it wont turn on or connect, change this in the build.prop:
ro.securestorage.support=true TO ro.securestorage.support=false"

 

[lilmul123]

You are the man! Looking forward to any developments!

---------- Post added at 01:39 AM ---------- Previous post was at 01:00 AM ----------

In case anyone else wants to try, I can confirm that the latest version of TWRP right now (2.8.1.0) for jfltetmo flashed using Odin does work on this phone. Obviously, it does trip the Knox bit, so if you'd prefer to hang onto your warranty in lieu of getting off a terrible ROM, don't do this.

 

[carlyman]

Wow..aromerblz, thanks for the detail!

Sent from my A0001 using XDA Free mobile app

 

[bommalattam]

Shouldn't we able to SIM unlock the phone using the steps for M919 using the steps from
http://xdaforums.com/showthread.php?t=2283068

if we are able to install the T-mobile ROM? or is it tied to the baseband version?

 

[aromerblz]

Shouldn't we able to SIM unlock the phone using the steps for M919 using the steps from
http://xdaforums.com/showthread.php?t=2283068

if we are able to install the T-mobile ROM? or is it tied to the baseband version?

You CANNOT SIM unlock via the SGH-M919 Method or any other ways. You cannot downgrade modem to access unlock menu. TracFone has the phone locked down pretty good. Not even unlock code unlocks this phone permanent. TracFone may have to provide a firmware update to fix this issue. Yes the modem/baseband is tied up really hard. Even if we find a way to flash another modem I believe it bricks the device.

 

[ndowens]

I used twrp installer on Google play to install
I hope this guide comes up soon. Still debating on returning this phone so I can get a nexus 5.

 

[aromerblz]

I used twrp installer on Google play to install
I hope this guide comes up soon. Still debating on returning this phone so I can get a nexus 5.

Am uploading the stock flashable ROM at the moment. since ill be at work i wont have the guide posted until later tonight. It will be pure stock with KNOX files removed.

 

[ndowens]

Am uploading the stock flashable ROM at the moment. since ill be at work i wont have the guide posted until later tonight. It will be pure stock with KNOX files removed.

Are you going to post how to create a custom rom for this device

 

[aromerblz]

Are you going to post how to create a custom rom for this device

This is what is used to create the ROM

http://xdaforums.com/showthread.php?t=633246

Custom ROMs am not venturing into them just yet. But any T-MOBILE custom ROM will work fine on this device.

 

[ndowens]

Do I need to use my kernel and does flashing a tmobile rom change the modem

 

[carlyman]

Along the lines of ndowens question.....by flashing a TMobile stock ROM, would/should we expect OTA updates as they are provided by TMobile (and if so, would that cause issues with the baseband or kernel)?

 

[ndowens]

The tmobile custom roms won't get ota updates

 

[carlyman]

Understood custom ROMs don't get OTA update....looking back at earlier posts it was mentioned the download/flash of the stock TMobile firmware. Probably a dumb question, but if I flash the stock Tmobile firmware (with a custom kernel) and then flash the S975L baseband...its now considered a custom ROM and thus no OTA updates?

 

[ndowens]

There is a possibility but I am not a expert in this stuff. If there was a update available don't take it

 

[aromerblz]

No OTA updates whatsoever. By doing all this OTA is disable becuase the binary flash counter is set to custom. Only way to update is by flashing based rom on the official firmware update. The modem cannot be changed since it does not accept nothing else that is not tracfone signed. So only parts that can be changed is the system, recovery, cache, and kernel. Am assuming tracfone will provide some sort of update to this devices to fix the unlock issue. As i dnt think no be happy that you must. Enter the unlock code every time you turn on the phone.

 

[ndowens]

I personally want to install a rom like pacman or similar on this thing