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

[MiamiMike]

Which specific rom and modem?

you on tmobile?

I'm running the Sprint SPH-L720, you can use ANY rom once you unlock the modem, however according to the post, you could get possibly get LTE with the M919 T-Mobile rom.
This has the M919 ROM, but it's unlock procedure doesn't work (FYI) http://forum.xda-developers.com/gal...l720t-gsm-unlock-att-tm-t3189063#post62587592

 

[EngineManShawn]

I have the Sph-l720t running on straight talk from Sprint. I have Sprint spark working. I was told I could only use 3g. Not true!I am using the original Sim from Sprint on my straight talk. It took multiple phone calls to get them to finally get me to LTE Spark. My phone was not rooted before this was done. They said a few times that my device was not LTE compatible but it can be done and I am proof. I had to call back for months on my renew date because it reverted back to 3g. This past month I had no issues. Like I said I needed the sprint Sim. There is an option in settings more that you can change to CDMA LTE and that needs to be done first and then you need to update your profile firmware etc. I don't know what effect it would have on your root access. Probably none. If not u may have to re root. Does this help?

 

[iBowToAndroid]

I have the Sph-l720t running on straight talk from Sprint. I have Sprint spark working. I was told I could only use 3g. Not true!I am using the original Sim from Sprint on my straight talk. It took multiple phone calls to get them to finally get me to LTE Spark. My phone was not rooted before this was done. They said a few times that my device was not LTE compatible but it can be done and I am proof. I had to call back for months on my renew date because it reverted back to 3g. This past month I had no issues. Like I said I needed the sprint Sim. There is an option in settings more that you can change to CDMA LTE and that needs to be done first and then you need to update your profile firmware etc. I don't know what effect it would have on your root access. Probably none. If not u may have to re root. Does this help?

You're getting LTE because you have it activated on the CDMA side of Straight Talk. When you're using it on GSM, LTE is not possible

 

[CapitalParallax]

I have the Sph-l720t running on straight talk from Sprint. I have Sprint spark working. I was told I could only use 3g. Not true!I am using the original Sim from Sprint on my straight talk. It took multiple phone calls to get them to finally get me to LTE Spark. My phone was not rooted before this was done. They said a few times that my device was not LTE compatible but it can be done and I am proof. I had to call back for months on my renew date because it reverted back to 3g. This past month I had no issues. Like I said I needed the sprint Sim. There is an option in settings more that you can change to CDMA LTE and that needs to be done first and then you need to update your profile firmware etc. I don't know what effect it would have on your root access. Probably none. If not u may have to re root. Does this help?

While technically a different device, I think you have the right concept.

I recently had another conversation with yet a different Straight Talk rep. Though every single one says something different, this most recent "reason" I don't get 4G makes the most sense thus far. According to the rep, my device is not accessing the 4G network because I do not have a Sprint SIM card in it. I've come to find that's really the whole purpose of the Sprint SIM. Had I been a Sprint customer, I would be seeing the same lack of 4G with no SIM. I haven't gotten around to it, but the general consensus of the internet is that I have the best chance to obtain one through Sprint's International Customer Support (despite not being a customer or international).
--

You're getting LTE because you have it activated on the CDMA side of Straight Talk. When you're using it on GSM, LTE is not possible

Why do you say that? Is that a hardware limitation of this particular variant, or a limitation of Straight Talk's stupidty? I had an Verizon Galaxy S4 getting 4G on Straight Talk's GSM side. I gave the phone to my gf and she was getting LTE on AT&T. I know, again, technically different devices, but close enough to speculate.

 

[EngineManShawn]

While technically a different device, I think you have the right concept.

I recently had another conversation with yet a different Straight Talk rep. Though every single one says something different, this most recent "reason" I don't get 4G makes the most sense thus far. According to the rep, my device is not accessing the 4G network because I do not have a Sprint SIM card in it. I've come to find that's really the whole purpose of the Sprint SIM. Had I been a Sprint customer, I would be seeing the same lack of 4G with no SIM. I haven't gotten around to it, but the general consensus of the internet is that I have the best chance to obtain one through Sprint's International Customer Support (despite not being a customer or international).
--


Why do you say that? Is that a hardware limitation of this particular variant, or a limitation of Straight Talk's stupidty? I had an Verizon Galaxy S4 getting 4G on Straight Talk's GSM side. I gave the phone to my gf and she was getting LTE on AT&T. I know, again, technically different devices, but close enough to speculate.

The sprint Sim was essential. Lucky when I bought the phone from a friend he had left it there. I did make a mistake earlier. I Have LTE /CDMA working. I believe the issue is that if you have Sprint spark my model does sph-l720t. Sprint doesn't want you to have Sprint spark and that is why it took so many calls and complaints. Eventually they give in and you can find a representative that will set it up. Sorry about that mix up. Now I just need to find all the tools that I need to use my rooted device to its potential. Want to get rid of all the garbage without doing any damage. Thanks

 

[CapitalParallax]

Now I just need to find all the tools that I need to use my rooted device to its potential. Want to get rid of all the garbage without doing any damage.

To that end, I highly recommend CyanogenMod. It was recommended to me as a good starting point to get into custom ROMs. It's the first and only one I've tried so far, and have been very happy with it. There's a healthy community of support and it was very easy to flash. It's probably the simplest way to strip all the crap and keep all the functionality.

 

[EngineManShawn]

To that end, I highly recommend CyanogenMod. It was recommended to me as a good starting point to get into custom ROMs. It's the first and only one I've tried so far, and have been very happy with it. There's a healthy community of support and it was very easy to flash. It's probably the simplest way to strip all the crap and keep all the functionality.

I'm going to attempt that tonight. Ty. I will be asking more questions I'm sure.!

 

[dpetchy0817]

Invalid SIM (Cricket)

I have a Sprint s4 with the MDC modem, on a debloated stock rom (4.4.2) currently, and I am trying to activate the device on Cricket wireless.

I have a brand new nano sim in the micro adapter inserted in the phone. The sim card is active with Cricket.

Fixed the invalid sim (turns out sprint didn't do the international unlock as stated).

I followed all the steps in the OP (did it three times to be sure I didn't mess up) and even tried a few corrections people made in the thread, my phone shows no signal. In the APN menu, I added the Cricket APN and that seems okay. In the about phone settings the phone number, network, and all that shows as unknown.

Any ideas? I really need to get off sprint as the service is terrible in my area (gotten much worse since I joined 10 years ago).

I read up to page 70 in here already and i'll keep reading but I'd appreciate some help.

 

[dpetchy0817]

No Audio

I have a Sprint s4 with the MDC modem, on a debloated stock rom (4.4.2) currently, and I am trying to activate the device on Cricket wireless.
I have a brand new nano sim in the micro adapter inserted in the phone. The sim card is active with Cricket.
Fixed the invalid sim (turns out sprint didn't do the international unlock as stated).
I followed all the steps in the OP (did it three times to be sure I didn't mess up) and even tried a few corrections people made in the thread, my phone shows no signal. In the APN menu, I added the Cricket APN and that seems okay. In the about phone settings the phone number, network, and all that shows as unknown.
.

Okay I completed the unlock, and have voice, text, and data. The issue i'm now having is that for calls or any app, video and audio will not play at all! I've tired stock, stock based, and cm12.1 roms with the same exact results .

Also mms doesn't work (on Cricket with the correct apn from their site).

Any ideas?

 

[iBowToAndroid]

Okay I completed the unlock, and have voice, text, and data. The issue i'm now having is that for calls or any app, video and audio will not play at all! I've tired stock, stock based, and cm12.1 roms with the same exact results .

Also mms doesn't work (on Cricket with the correct apn from their site).

Any ideas?

Why are you on MDC modem...????

That's your issue.

 

[dpetchy0817]

Why are you on MDC modem...????

That's your issue.

I've tried several times to update the modem via odin, and it wouldn't stick. I somehow just tripped the "system software not authorized by samsung" message so had to reflash the whole phone to the stock rom in odin. That is setting up now. I used the NG2 tar, so I think I should be good. Does that sound about right?

 

[iBowToAndroid]

I've tried several times to update the modem via odin, and it wouldn't stick. I somehow just tripped the "system software not authorized by samsung" message so had to reflash the whole phone to the stock rom in odin. That is setting up now. I used the NG2 tar, so I think I should be good. Does that sound about right?

Yep

 

[anthony.j.etienne]

Hey guys I unlocked my S4 and using it on simple mobile. My problem is getting voicemail set up for simple mobile with the new number? The phone number shows the sprint number in settings > about. What should I do?

 

[Duwhop31]

S4 SPh-720

Ok I did all the way down to adding the ril-lol & ro-lol & manually restarted my phone & now it wont turn on at all.. it will vibrate & say the galaxy s4 logo then it shuts off. How do I get to come.bak on? Its 100% charged. Thanks, Dallas.

 

[iBowToAndroid]

Ok I did all the way down to adding the ril-lol & ro-lol & manually restarted my phone & now it wont turn on at all.. it will vibrate & say the galaxy s4 logo then it shuts off. How do I get to come.bak on? Its 100% charged. Thanks, Dallas.

Rule #1: never follow an OP that is almost 2 years out of date

 

[Duwhop31]

What to do

@iBowToAndroid what can I do now? Or how do I get it to @ least turn on? Sorry & thanks....

 

[mattzeller]

@iBowToAndroid what can I do now? Or how do I get it to @ least turn on? Sorry & thanks....

Can you get into download mode? (Volume - & power}

 

[Duwhop31]

Re

Yes but it wont even stay on it cuts off then cuts on to thw logo & off agin. I thnk maybe the battery but I.just put it on the charger & it says 59% & I think it is charging...

 

[Duwhop31]

S4 SPh-720

@iBowToAndroid I.just plugged my s4 n & it says 94% soo it cant b battery right? & I can get to that dwnload where it says to hit vol up or dwn to cancel.. what do I do there or then?

---------- Post added at 10:26 PM ---------- Previous post was at 10:08 PM ----------

@iBowToAndroid this is what is says when I hit vol up after holding vol dwn & power
Current binary custom
System status custom
Reactivation lock off
Knox kenel lock 0x0
Knox warranty void 0x1
CSB-CONFIG-LSB 0x30
Secure download enable
Enable
Enable

 

[mattzeller]

@iBowToAndroid I.just plugged my s4 n & it says 94% soo it cant b battery right? & I can get to that dwnload where it says to hit vol up or dwn to cancel.. what do I do there or then?

---------- Post added at 10:26 PM ---------- Previous post was at 10:08 PM ----------

@iBowToAndroid this is what is says when I hit vol up after holding vol dwn & power
Current binary custom
System status custom
Reactivation lock off
Knox kenel lock 0x0
Knox warranty void 0x1
CSB-CONFIG-LSB 0x30
Secure download enable
Enable
Enable

Go into download mode, and flash stock via Odin from sammobile.com