Develop Bugs

Tmobile S4 on AT&T cannot connect to LTE help!

Hey everyone!
So I picked up a tmobile s4 to use on ATT since I read it was the most unlocked due to bands / bootlocker. I unlocked it via the method described on this site via the debug menu.
Popped in ATT sim, everything looked fine initially.
1. I'm only getting 4G in an LTE area. device hasn't picked up any LTE anywhere yet.
2. When I go under "Network Mode" and select "LTE/GSM/WCDMA (auto connect) the signal dies out and it always reverts back to GSM/WCDMA"
3. I've called ATT a few times and triple checked that I'm on an Android LTE data plan, so that's not an issue. ATT techs suggested it could be a device issue and maybe I should take it into their tech center.
4. Tried to set up ATT Visual Voicemail, that failed also.
So can it be a Sim issue? Maybe something on tmobiles side? Since device was never active on their network. A lemon S4?
I've run out of options
Any help would be appreciated.
TIA!

qidrox said:
Hey everyone!
So I picked up a tmobile s4 to use on ATT since I read it was the most unlocked due to bands / bootlocker. I unlocked it via the method described on this site via the debug menu.
Popped in ATT sim, everything looked fine initially.
1. I'm only getting 4G in an LTE area. device hasn't picked up any LTE anywhere yet.
2. When I go under "Network Mode" and select "LTE/GSM/WCDMA (auto connect) the signal dies out and it always reverts back to GSM/WCDMA"
3. I've called ATT a few times and triple checked that I'm on an Android LTE data plan, so that's not an issue. ATT techs suggested it could be a device issue and maybe I should take it into their tech center.
4. Tried to set up ATT Visual Voicemail, that failed also.
So can it be a Sim issue? Maybe something on tmobiles side? Since device was never active on their network. A lemon S4?
I've run out of options
Any help would be appreciated.
TIA!
Click to expand...
Click to collapse
are you using stock ROM?

Rattles said:
are you using stock ROM?
Click to expand...
Click to collapse
Yes I am, I guess I should've mentioned that

Apparently my data stopped working now too. No data at all

qidrox said:
Apparently my data stopped working now too. No data at all
Click to expand...
Click to collapse
Ok so after changing some options around in network i have 4G back up and running. Its on WCDMA/GSM now.

Did you check the apn to make sure its correct for att?
Sent from my SGH-M919 using xda premium

qidrox said:
Hey everyone!
So I picked up a tmobile s4 to use on ATT since I read it was the most unlocked due to bands / bootlocker. I unlocked it via the method described on this site via the debug menu.
Popped in ATT sim, everything looked fine initially.
1. I'm only getting 4G in an LTE area. device hasn't picked up any LTE anywhere yet.
2. When I go under "Network Mode" and select "LTE/GSM/WCDMA (auto connect) the signal dies out and it always reverts back to GSM/WCDMA"
3. I've called ATT a few times and triple checked that I'm on an Android LTE data plan, so that's not an issue. ATT techs suggested it could be a device issue and maybe I should take it into their tech center.
4. Tried to set up ATT Visual Voicemail, that failed also.
So can it be a Sim issue? Maybe something on tmobiles side? Since device was never active on their network. A lemon S4?
I've run out of options
Any help would be appreciated.
TIA!
Click to expand...
Click to collapse
Dial *#*#4636*#*# go under phone and scroll down and select the mode you want then reboot.
Sent from my SGH-M919 using Xparent Skyblue Tapatalk 2

Soldier 2.0 said:
Dial *#*#4636*#*# go under phone and scroll down and select the mode you want then reboot.
Sent from my SGH-M919 using Xparent Skyblue Tapatalk 2
Click to expand...
Click to collapse
Tried doing that. It says " USSD Code running" then it stops and states "Unable to process request"... I dont think that was normal?

Yeaaaayuh!
qidrox said:
Tried doing that. It says " USSD Code running" then it stops and states "Unable to process request"... I dont think that was normal?
Click to expand...
Click to collapse
Figured it out!!! Did a google search and noticed my APN values were wayyy off. Changed them. BAM LTE!! :laugh::good:
Thanks to all that helped!

Share those setting to help others !!!!!!!!

nmccready said:
Share those setting to help others !!!!!!!!
Click to expand...
Click to collapse
Go to settings> more networks>mobile networks> access point network> and change your settings to look like these....
In the "APNs" window just hit the + button to creat a new APN
Sent from my SGH-M919 using XDA Premium 4 mobile app

Thank you!
I also found the setting from here:
https://www.youtube.com/watch?v=gMyD8zqk-Hg which led to here: http://forum.xda-developers.com/showthread.php?t=2336085 .
The main end game fix was that ATT had my IMIE # incorrectly set. Once they fixed that my LTE was a go!
:good: :laugh:

[Q] How turn on only lte?

How turn on only lte on t805? Thanks for attention

crzcraft said:
How turn on only lte on t805? Thanks for attention
Click to expand...
Click to collapse
Think you have to be rooted. Install the app Advanced Signal Status and under "additional info", then "device info" you can choose for different options.

crzcraft said:
How turn on only lte on t805? Thanks for attention
Click to expand...
Click to collapse
when I am using my galaxy note 3, I input *#2263# to go to a menu where I can force LTE/WCMA my device and mostly it connects to only LTE.
in the Galaxy tab S , the code works but the option for LTE only is missing. so now I continuously connect to a slow 3g network.. bummer...
*UPDATE:
apparently you have to deselect all GSM bands and just select all LTE and WCMA bands.. you wont be able to use GSM bands but your device will lock on to LTE connections if avaialbe, 3g will apply if LTE is unavailable. hope this helps

LTE

Hi i have just purchased the z1 compact second hand from ebay and i cannot find any setting forLTE in mobile networks i can only select wcdma only/gsm only/ and wcdma prefred. My sim card is on the UK 3 network and previously was working on LTE.

Well is fine here.factory reset?

no LTE
zlata said:
Well is fine here.factory reset?
Click to expand...
Click to collapse
No good look this is mine.

sam0056 said:
No good look this is mine.
Click to expand...
Click to collapse
What about SERVICE menu?
Dial *#*#7378423#*#* and go to Service Info>Configuration. You should get something like the first attachment.
Also, You can check under *#*#4636#*#* and then check the set preferred network type like attachment 2.

fixed Lte
Mirhawk said:
What about SERVICE menu?
Dial *#*#7378423#*#* and go to Service Info>Configuration. You should get something like the first attachment.
Also, You can check under *#*#4636#*#* and then check the set preferred network type like attachment 2.
Click to expand...
Click to collapse
OK i managed to fix it by flashing a stock Kitkat rom from Central Europe. After flashing the stock rom LTE is now showing up and working guess ill just stick with KitKat for now

Note 4 N910A No 3G?

Hello! I got my ATT Note 4 yesterday and 4g LTE works fine but for some reason I can't get 3g to work on it. I tried going to "mobile networks" but i couldn't find the "network mode" so i can't choose which I want so i used the code "*#*#4636#*#*" and tried setting it to "WCDMA Preferred" then "WDCMA Only" and "GSM/CDMA Auto" but i still don't get 3g.
My mobile carrier is Cricket
Thanks for reading!

Y do want to 3G 4G faster
Sent from my Samsung Galaxy Note 4 using XDA Labs

Just a guess, you might not have 3G APN setting in your phone. Try different sim and test 3g on it. If it works then u need settings or new sim. If dont then take your phone to carrier customer center and they will help you.

No 4G/LTE even after hiddenmenu sim unlock

Hi,
I can get edge 2G or 3G but not LTE/4G although I followed the hidden menu sim unlock tutorial and put the ModemProtocol, Network Mode to Automatic and RAT Selection, put GSM/WCDMA/LTE Auto but it doesn't give me LTE.
I also tried enabling LTE from the ##3282# screen, but I still didn't get LTE.
Thanks for help.
Using LG G5 LS992ZVA.

In ##3282#
LTE
LTE roaming enable (on)
Need this to take 4g

adop_19 said:
In ##3282#
LTE
LTE roaming enable (on)
Need this to take 4g
Click to expand...
Click to collapse
It is greyed out and I can't edit it.

Turn of LTE

I tried, it is still greyed out.

adop_19 said:
Turn of LTE
Click to expand...
Click to collapse
Any new help? Thanks.