[Q] G900T Mobile Data not working on ATT

[1337free]

My friend purchased a G900T that was broken for parts, which needed a new screen. Upon replacing the screen, the phone was functional, but he discovered that the IMEI number had been blacklisted on T-Mobile's network. We unlocked the phone to use it on ATT, and the device works fine on the ATT network, with the exception of mobile data. No matter what steps we have taken, putting in custom APN settings, we have not been able to get data to function.

Does anybody have any suggestions as to what might be causing these issues?

Thanks a lot in advance! :good:

 

[Pikaberdot]

Have you tried to flash an AT&T ROM & AT&T Modem?
Or are you still running T-Mobile ROM & Modem?

 

[1337free]

Still running the stock Tmobile rom and modem. I thought about switching to ATT rom and modem, but I wasn't sure if that would brick the phone or if it should just work with the stock Tmobile modem. Can I just flash an ATT rom?

 

[Pikaberdot]

Just make a Nandroid beforehand.

T-Mobile S5 comes w an unlocked boot loader so you shouldn't have any problem. You put in an AT&T SIM card right?

 

[highaltitude]

You do not want to flash AT&T firmware on a Tmobile phone unless you are looking to brick it. You can however flash ROM's from Unified S5 threads (900F, 900T etc.) that are open to multiple model phones.

 

[1337free]

So if I flashed one of the unified roms, would that change the modem at all? I was thinking that it wouldn't be part of the package. Would just flashing an att modem be a terrible idea? I am using an Att sim card. Thanks for the ideas so far!

 

[Commodore 64]

No, do not flash an att modem or ROM on a tmo device. It won't work, and it is not meant to work.

Does your subscription have an active smartphone data plan?

Are you getting any data connection (E, 3G, or 4G)_and you're not able to jump on the LTE or just no data at all?

If the answers to above questions are yes, there are a few more things att checks for before authenticating data use on a device.

These fields need to look exactly like this:

ro.product.model=SAMSUNG-SM-G900A
ro.product.name=klteuc
ro.product.device=klteatt
ro.build.product=klteatt

This information lives in the build.prop file of your android OS and you're gonna have to look up how to back up and edit this file. Start off here http://forum.xda-developers.com/showthread.php?t=1948558 and keep on reading. I kbow this is exciting and you want to make it work quickly but it is not so simple. So reading and researching are your best friends.

Best of luck,

Sent from my SAMSUNG-SM-G900A using XDA Free mobile app

 

[1337free]

Okay, thanks for the info! We are just plain not getting any data at all, and the user does have an active data plan with ATT. MMS messages are not even able to be sent or received. So in this instance, do you think modifying the build.prop to match the example you gave me would resolve the issue? I'm pretty comfortable working with the build.prop on the device and just working the the Android OS in general so that should not be a problem.

 

[Commodore 64]

So I guess checking the APN settings won't be a bad idea:

http://forum.xda-developers.com/showthread.php?t=2975336

[Q] Tips on using a G900T on AT&T

See if the APN matches with this one, and toggle airplane mode on/off each time you change things in APN.

Sent from my SAMSUNG-SM-G900A using XDA Free mobile app

 

[1337free]

Okay, I had checked APN settings before, but I'm not sure if they were specific to the S5 on ATT or just some generic ATT one I found. That thread looks pretty helpful, I'll see if I can give it a shot later today.

 

[Commodore 64]

You may also consider loading an international ROM for example http://forum.xda-developers.com/showthread.php?t=2732110
Is an excellent ROM



Sent from my SAMSUNG-SM-G900A using XDA Free mobile app

 

[gspears]

I know it's a foolish question, but you never know. Are you sure your mobile data is not turned off? My wife did that a while back.

 

[tlopez1973]

I'm running a AT&T rom on my t-mobile s5 with out any problems as a matter of fact I have better signal.i just flashed rom not modem

 

[1337free]

Well thank you to everybody for insight into this. The link that Commodore 64 posted pertaining to the APN settings ended up fixing these issues. I had input different ATT APN settings I found in a different thread previously, but I guess they must not have been right. Still running the stock Tmobile rom and we are now able to get data and 4G with really good speeds.

Cheers!

 

[Quickvic30]

Well thank you to everybody for insight into this. The link that Commodore 64 posted pertaining to the APN settings ended up fixing these issues. I had input different ATT APN settings I found in a different thread previously, but I guess they must not have been right. Still running the stock Tmobile rom and we are now able to get data and 4G with really good speeds.

Cheers!

May I ask what APN settings you are running? With the APN settings I'm using I get full 4G LTE data just about everywhere I go, besides way out in the stix then I get 4G in some spots.

Sent from my SM-G900T on ATT

 

[1337free]

May I ask what APN settings you are running? With the APN settings I'm using I get full 4G LTE data just about everywhere I go, besides way out in the stix then I get 4G in some spots.

Sent from my SM-G900T on ATT

I'm using the APN settings in this post http://forum.xda-developers.com/showthread.php?t=2975336