[HOWTO] / [GUIDE] SPH-L720 Domestic SIM Unlock T-Mobile:AT&T:metroPCS:Straighttalk

[ciabatoni]

check

I did one for someone today and everything was good besides this problem here, theres was outdated, Worth a look http://www.att.com/esupport/article.jsp?sid=KB424489&cv=820#fbid=kx8PBQjxTph

 

[lisac2100]

so i have a sprint s4 carrier unlocked running a tmobile 4.4.2 custom gummy rom ( mdc ) w a straightalk sim. i can send/recieve text just fine, use the net. and place calls, all with no issues. i can not however recieve any calls. my phone does not ring on my end. has anyone experienced this issue and have a solution?

 

[iBowToAndroid]

so i have a sprint s4 carrier unlocked running a tmobile 4.4.2 custom gummy rom ( mdc ) w a straightalk sim. i can send/recieve text just fine, use the net. and place calls, all with no issues. i can not however recieve any calls. my phone does not ring on my end. has anyone experienced this issue and have a solution?

go back to stock rom

 

[lisac2100]

go back to stock rom

so i would go to stock sprint rom and use that with the straight talk??

 

[ecs87]

go back to stock rom

EXACTLY! The unlocks are enough of a hack...now people want to throw a custom ROM on top of it?! That's just asking for trouble (unless it was made by a dev suited to this particular device and scenario).

Sent from my LGLS990 using XDA Free mobile app

 

[daniel4653]

EXACTLY! The unlocks are enough of a hack...now people want to throw a custom ROM on top of it?! That's just asking for trouble (unless it was made by a dev suited to this particular device and scenario).

Sent from my LGLS990 using XDA Free mobile app

Ive been running custom Roms OK my gs4 since I unlocked it about 3 months ago . from sacs ROM to negaman, hyperdrive, aokp, paranoid android, slim ROM, etc.

 

[ecs87]

Ive been running custom Roms OK my gs4 since I unlocked it about 3 months ago . from sacs ROM to negaman, hyperdrive, aokp, paranoid android, slim ROM, etc.

I've heard of too many issues from other users on custom ROMs. Maybe you need to write a tutorial on how to properly flash a custom ROM lol.

Sent from my LGLS990 using XDA Free mobile app

 

[daniel4653]

I've heard of too many issues from other users on custom ROMs. Maybe you need to write a tutorial on how to properly flash a custom ROM lol.

Sent from my LGLS990 using XDA Free mobile app

Lol honestly I do nothing special.

 

[lisac2100]

Lol honestly I do nothing special.

can anyone thats on straight talk or tmobile post a modem and kernel so that i can flash those with stock and/or custom rom to see if maybe one of those 2 things are the problem?

 

[maurogg84]

can anyone thats on straight talk or tmobile post a modem and kernel so that i can flash those with stock and/or custom rom to see if maybe one of those 2 things are the problem?

You said you have a 4.4.2 Rom, is that aosp or a modified stock? What's your build number? As far as I know, some modems don't work well with different builds that have different firmwares. If your build is NAE, flash the NAE modem to see if that fixes the problem, and also the NAE kernel if you are stock. You'll have to look that up.

Sent from my SPH-L720

 

[bittle21]

Factory reset and unlock

Could someone please explain the best way to do a factory reset with this unlocking method? I recently upgraded to the Galaxy Note 4 and want to give my son my S4 as a Christmas gift. He currently has Cricket service and I've included a screenshot with (hopefully) all necessary details. Thanks in advance for your help and all the hard work put into maintaining this thread.

 

[bittle21]

Could someone please explain the best way to do a factory reset with this unlocking method? I recently upgraded to the Galaxy Note 4 and want to give my son my S4 as a Christmas gift. He currently has Cricket service and I've included a screenshot with (hopefully) all necessary details. Thanks in advance for your help and all the hard work put into maintaining this thread.

Forgot to mention, this phone is rooted and running stock ROM.

 

[daniel4653]

Could someone please explain the best way to do a factory reset with this unlocking method? I recently upgraded to the Galaxy Note 4 and want to give my son my S4 as a Christmas gift. He currently has Cricket service and I've included a screenshot with (hopefully) all necessary details. Thanks in advance for your help and all the hard work put into maintaining this thread.

Depends of.you want to wipe the phone completely or if you want to just wipe the phone for a regular ROM install.

 

[bittle21]

I want to completely factory reset, keep stock ROM, and also keep root. Then do the unlock... Is this asking too much of my beloved S4? Lol

 

[daniel4653]

I want to completely factory reset, keep stock ROM, and also keep root. Then do the unlock... Is this asking too much of my beloved S4? Lol

Haha no not.too much. Just do.the factory reset in recovery, then downgrade the modem and perform the international unlock then the domestic unlock. I'm using my GS4 on Cricket

 

[bittle21]

Oh ok, reset in recovery keeps root. Thanks for the help, I'll update later whether or not it's successful

 

[warriorpluto]

Hey I did this on 720t and didn't know I had the tri band version. How do I connect it back to Sprint? I did you small steps.

 

[ecs87]

Hey I did this on 720t and didn't know I had the tri band version. How do I connect it back to Sprint? I did you small steps.

Set the network mode in settings back to CDMA/LTE.

Sent from my LGLS990 using XDA Free mobile app

 

[bittle21]

Success!

I found the time to try this today and while it was a bit nerve-wracking, it was completely successful. HSPA+ working on AT&T

Now just waiting till Christmas, then to plug in the APN settings for Cricket.

Thanks again to everyone who has contributed to this thread. It brings a HUGE sense of accomplishment to me knowing I was able to do something that Sprint customer service couldn't/wouldn't do.

 

[bittle21]

Just a few screenshots