Develop Bugs

[Q] Sim not found

hey,
my android was getting a bit slow, so i restarted my phone.
after that the phone said sim not found.
i tried everything, restarting a few times, locking bootloader and i even flashed my rom back to full stock.
but still no success.
what do i need to do?
thanks in advance

Denniz0229 said:
hey,
my android was getting a bit slow, so i restarted my phone.
after that the phone said sim not found.
i tried everything, restarting a few times, locking bootloader and i even flashed my rom back to full stock.
but still no success.
what do i need to do?
thanks in advance
Click to expand...
Click to collapse
Maybe bad connection on your sim card?
Try removing the SIM card and put it back in, and then boot the phone.
Sent from my Galaxy Nexus using Tapatalk

done that, doesn't help

Im getting hte same issue. The 4.0.2 update came through, rebooted the phone. SIM not found, press to reboot....
Rebooted, SIM still not working. remove SIM and replace. Still not working. replaced with another SIM. Still not working.
Was working fine prior to the 4.0.2 update. This is on a 1 month old phone that has never been rooted. It is still as stock as it comes out of the box... And i want to test it more before i start boxing it up to send it back...

Have you tried leaving the battery out for a bit, then trying powering it up again?

Here is where it gets weird. I tried 2 other sim cards as well as my own. none of them worked. put my sim card back in and tried again, still not working. turned it off over night. went to Vodafone and asked if i could try a new SIM in the phone. still not working. put my TPG/Optus sim in and it started working. got a new SIM from Voda, transfered all the account info to the new card, waited an hour and tried it again and now it works :/
Dont know what caused it to stop working and dont know what caused it to start working again :/ im going to throw the word "Vodafone" in there as the cause because people will just nod their head and say... "yep, that was probably it..."

I have the same issue with AT&T....the phone does recognize the SIM, APN and all...but no signal. Just once in a while it gets registered on teh network, but for one minute or so...I don't know what to do

Same issue here, after a reboot my phone does not recognize my sim at all. no signal at all. tried a different sim, nothing, bought a new sim but nothing again, returned to stock, everything, but still nothing....no remedy yet....

[Q] *HELP!*T-Mobile Galaxy S II Network Problem

OK guys i'm a complete noob here at XDA (registered yesterday) but i'm getting really desperate and confused and since i've seen XDA is such a great community i thought i'd give it a shot...
My GSII had been running BeastMOD ROM II v3.0 for about a month now and it worked like a dream but about 3 days ago i turned off my phone and then turned it back on a minute later and I HAD NO NETWORK!! Now, that i recall i didn't do anything to cause this. I called t-mobile and went through all their troubleshooting, no luck. I flashed BeastMOD ROM II v4.2, no luck. Re-flashed BMOD 3.0, no luck. I noticed i don't get ping to my network, I have no IMEI number(i get null/null), and no baseband version(unknown). I'm really worried and hopefully you guys can help me some suggestions ASAP as i haven't had network in three days.

restore a back up of your stock if you still have it.

and this will only get me back to stock and not undo root or will it? will try

Here's what happens. I try to do my first stock ROM restore and it says
"Checking MD5 sums...
MD5 mismatch!" <--Whats wrong? I'm currently doing a restore on a backup three hours after that one which i'm not sure which one it is (maybe the first backup after i installed BMOD 3.0) but hopefully it will do something.

http://forum.xda-developers.com/showthread.php?t=1325036
http://forum.xda-developers.com/showthread.php?t=1433819
http://forum.xda-developers.com/showthread.php?t=1336915
read up, they are different phones but might have common factor
to fix i think:
http://forum.xda-developers.com/showthread.php?t=1462870

mrpagercao said:
http://forum.xda-developers.com/showthread.php?t=1325036
http://forum.xda-developers.com/showthread.php?t=1433819
http://forum.xda-developers.com/showthread.php?t=1336915
read up, they are different phones but might have common factor
to fix i think:
http://forum.xda-developers.com/showthread.php?t=1462870
Click to expand...
Click to collapse
Hey thanx for that last link but the freakin person that made that method just bailed on me after his method screwed with my phone. I have stock now but i have a problem where my phone keeps rebooting until it gets network and even after it finds network and gets its IMEI and Baseband version back, that "fix" doesn't let me use data and for some actions the phone says the SIM card is not ready or available. and when i turn off the phone and back on it keeps rebooting until it finds network like i said. I don't know what the EFS is but that could be something that is making the phone malfunction. Please! Someone help!

i had almost the same problem.
My IMEI is still there, but it just won't connect to any network! All of a sudden, I woke up and it wont connect!
I'm getting a replacement sent to me from tmobile. weird.

[Q] Lost IMEI now stuck in boot loop after ODIN to stock

Hello,
I'm having a lot of difficulty getting my Note II (SGH T889V) in working order . I'll try to explain the situation in an organized way. Thank you for your time and kind help!
Background
I have a Note 2 from Wind Mobile in Canada - SGH T889V. I got it 2.5 months ago. It was rooted, was running TWRP and I only loaded one ROM, flashed once, on it - 4.1.2 modified touchwiz ROM. Never once had an issue. The ROM was super stable and in great working order.
I got it unlocked about 2 weeks ago because I was visiting the states. When I got to the states, I put in a T-Mobile sim card which was working great for a few days. One afternoon during my vacation I was having slow data issues, so I thought to change the modem/radio from a Wind Mobile radio to a T-Mobile radio. That gave me 4G data speeds but killed my calls. So I tried to go back to the Wind Radio and that had my phone complaining that there was no SIM card. I went back to the T-Mobile radio and I got calling back but only 2G data.
My IMEI was corrupted - it showed up as zero. I left the T-Mobile radio on the phone when I got back. My home network wouldn't recognize me and thought I was still roaming.
Attempted Fixes
Tried a basic factory reset. Tried a different ROM. Tried wiping all internal data.
I got home and tried to flash to stock ROMs found on XDA for Wind Mobile phones. That didn't solve the issue. The IMEI remained null. The phone would reboot automatically every few minutes unless I turned Airplane Mode on. I figure the phone was looking for a signal and couldn't because of the IMEI problem.
So I looked around on the net and found a link about injecting the IMEI back using QPST (http://forum.xda-developers.com/showthread.php?t=1206275) but I couldn't get the program to detect my phone so I gave up and thought I could just get my binary count to 0 and stock and I'll just take it back for warranty.
I tried Triangle Away but I couldn't get the counter to go to 0 even with stock ROM and recovery. So I thought I would take it to a cell repair shop locally. I took it there and all they did was cause an issue on the phone to make it appear that KIES firmware upgrade failed so that it would be repaired under warranty. You would see a emergency firmware upgrade error the minute you turned the phone on. However, download mode still showed the custom binary count at 1, they didn't get it down to 0.
I spoke with my carrier and with Samsung anonymously, they said the counter would be an issue if I sent it in.
I came back home and tried doing the following, with the hopes of trying Triangle Away again:
1. Installed TWRP via ODIN and ran the restore on the backup I created in TWRP when I first got the phone. I restored everything including EFS. Phone boots to the stock samsung rom but it would restart automatically every few minutes. Even with Airplane mode on, it would still reboot on it's own.
The KIES error message doesn't appear anymore.
2. Went back to ODIN. It was getting stuck on SYSTEM in ODIN version 3.07 when flashing a stock rom. So I switched the USB port on my computer and used ODIN 3.04 then the flashes went through properly with no hang ups.
So I tried to flash a prerooted (http://forum.xda-developers.com/showthread.php?t=1975560&highlight=wind) stock ROM
and
also a basic stock ROM (http://forum.xda-developers.com/showthread.php?t=2061031), along with a stock recovery
Both just get stuck in a bootloop. I tried going to the stock recovery and wiping data, cache, factory reset several times. No luck - still boot loops. Wont go into the ROM.
I did not try "Re-partition" in ODIN. I'm not sure if that'll hard brick the device but maybe that way I can repair all of the partitions? - http://forum.xda-developers.com/showthread.php?t=860432&page=2
__________
Im hoping to get back into a prerooted ROM or stock ROM to try this Triangle Away Method - http://forum.xda-developers.com/showthread.php?t=2272966 to get the custom binary down to zero.
I tried to use the Triangle Away ODIN method but it doesnt go through in ODIN, it just gets stuck.
If I can get into the ROM without it boot looping or rebooting automatically- I think I can fix my IMEI like this person did - http://forum.xda-developers.com/showthread.php?t=2145967
Outcomes Im hoping for
To stop the bootlooping/ automatic reboots, then
1. To get the custom Binary count to 0 so I can send it back in for warranty to Samsung or my carrier, Wind Mobile. The binary says Samsung Official. - http://forum.xda-developers.com/showthread.php?t=2068156
or
2. To get the phone to working order so I can try this persons method - http://forum.xda-developers.com/showthread.php?t=2145967
The phone is still responding and it's still working with ODIN. It makes me think the issue is software or partition related and not hardware related per se. If it is hardware, I just want to get this phone back to Samsung but I need to unroot/clear the binary counter.
The phone has never been dropped or damaged physically. I've really babied the phone. This is my third Samsung Galaxy phone (I've had a Vibrant and S2x before this one.)
This has really ruined my week. I need my phone for work. I greatly appreciate any kind help or guidance. I know the collective genius here at XDA will be able to find a solution.
Thank you so much!

If you have flashed the tmobile modem you will now have to keep the tmobile one in order to get your phone to boot. Flashing a t889v modem will cause loops. Dont know of any way to get back to t889v modems.

Hey, don't worry, you aren't the first to experience this problem. Many users have reported that the T889V will bootloop with the T889V modem after flashing another modem. Many have also restored IMEI and service to their phones, so there is a solution. I don't have the specifics, but there are many threads about this problem with solutions. I have quickly searched for one and I believe it has everything you need to fix it.
http://forum.xda-developers.com/showthread.php?t=2119074&page=3

Byangmang said:
Hey, don't worry, you aren't the first to experience this problem. Many users have reported that the T889V will bootloop with the T889V modem after flashing another modem. Many have also restored IMEI and service to their phones, so there is a solution. I don't have the specifics, but there are many threads about this problem with solutions. I have quickly searched for one and I believe it has everything you need to fix it.
http://forum.xda-developers.com/showthread.php?t=2119074&page=3
Click to expand...
Click to collapse
Thank you. I'm going to give that a shot. I'll install CWM then install a T889 TMobile Radio to see if it boots.
I'll report back. Fingers crossed.

I had same issue... this is how I fixed it
http://forum.xda-developers.com/showthread.php?t=2274843

sniperess said:
I had same issue... this is how I fixed it
http://forum.xda-developers.com/showthread.php?t=2274843
Click to expand...
Click to collapse
Thank you all!
I got the boot loops to stop by flashing CWM recovery, then flashing a TMobile Radio.
From there, I followed the QPST instructions of installing a QCN file on the phone to reenable the AWS spectrum. Then I used the IMEI creator and NV Writer programs and I was back.
Data seems alright, getting alright speeds on Wind right now. I just found my bluetooth a little hard to hear in the car this morning.
So with this process, I should stick with a Tmobile radio from now on right? If I flash a Wind/ T889V modem it'll boot loop?
Have you guys noticed any signal or performance issues after restoring the phone this way? I'm wondering if it's worth the trouble to get the custom binary counter to clear and return this phone for warranty. Seems to be working for the most part so far.
Thank you so much again! I thought I was going to have to pay $100 to get it JTAGed.

Glad to here your back and running.
I have a t889v using it on telus, and since I am stuck on tmobile modem I get lower phone signal but never loose signal. On a plus I now get lte speeds.

First day back it seems good for the most part.
Only issue I had was Bluetooth in my car would cut out at a high rate of speed (when I was on the highway). It worked really well while I was on local roads but once I hit the highway I couldn't hear the other side at all pretty much. I had to put them on speaker to hear them. They could hear me really well, better than before when I was driving on local roads.
Never occurred in the past. Could it be a radio issue? Signal seemed okay and I was able to continue the conversation over the phone speaker on the highway.

lilroach said:
First day back it seems good for the most part.
Only issue I had was Bluetooth in my car would cut out at a high rate of speed (when I was on the highway). It worked really well while I was on local roads but once I hit the highway I couldn't hear the other side at all pretty much. I had to put them on speaker to hear them. They could hear me really well, better than before when I was driving on local roads.
Never occurred in the past. Could it be a radio issue? Signal seemed okay and I was able to continue the conversation over the phone speaker on the highway.
Click to expand...
Click to collapse
The bluetooth issue doesn't seem to be a problem anymore. Disappeared on it's own.

lilroach said:
The bluetooth issue doesn't seem to be a problem anymore. Disappeared on it's own.
Click to expand...
Click to collapse
I noticed I have serious data issues when the network goes into HSPA+ mode. I get really good data for a minute then it'll cut out totally for like an hour. I tried rebooting, tried battery pulling. It seems the T-Mobile radio doesn't interface well with Wind's HSPA+ . I had full bars but the internet wouldn't load. It was pretty non-functional for most of the day.
It works decently when it's not on HSPA+
Tried switching to a Wind modem, went into boot loops. Went back to T-Mobile radio. Should I try a different T-Mobile radio?

how to fix your T889v if you accidentally overwrite the radio
If you get stuck with no IMEI, in my case, flashed omnirom 4.4.1 t0ltetmo, which uses Tmobile radio... it killed the Wind Mobile radio... restoring form nandroid did not help.
solution:
flash omnirom t0lte (not t0ltetmo) and your problems are gone!
lilroach said:
I noticed I have serious data issues when the network goes into HSPA+ mode. I get really good data for a minute then it'll cut out totally for like an hour. I tried rebooting, tried battery pulling. It seems the T-Mobile radio doesn't interface well with Wind's HSPA+ . I had full bars but the internet wouldn't load. It was pretty non-functional for most of the day.
It works decently when it's not on HSPA+
Tried switching to a Wind modem, went into boot loops. Went back to T-Mobile radio. Should I try a different T-Mobile radio?
Click to expand...
Click to collapse

[Q] Baseband Version Unknown!!!! Help

A few days ago I purchased a Verizon Galaxy Note 2 off of Craigslist. When the guy brought it to me I was able to test the phone with my 4G chip. It was able to make calls and access the internet. Once I got home I noticed that the phone would constantly go into a Demo mode and erase any changes that I had made to the phone. Instead of calling the guy that sold me the phone I decided I would just go ahead and root it.
The first attempt at rooting the phone ended up as a disaster. It was constantly rebooting after the splash screen. I later found that this was an easy fix. I had decided to "Nand erase All" and then it would not even boot. I finally found a Root66, the phone came up fine but I had no connection to Verizon with or without the 4g chip. I looked through the phone settings and found that under the "Baseband Version" it said unknown. Since then I have tried flashing in with other roms. Right now its flashed with KIES_HOME_I605VRAMC3_I605VZWAMC3_1098177_REV04_user_low_ship.tar.
Its still says the Baseband Version is Unknown and the only thing that works is the wifi.
Please HELP!!!

darcy6901 said:
A few days ago I purchased a Verizon Galaxy Note 2 off of Craigslist. When the guy brought it to me I was able to test the phone with my 4G chip. It was able to make calls and access the internet. Once I got home I noticed that the phone would constantly go into a Demo mode and erase any changes that I had made to the phone. Instead of calling the guy that sold me the phone I decided I would just go ahead and root it.
The first attempt at rooting the phone ended up as a disaster. It was constantly rebooting after the splash screen. I later found that this was an easy fix. I had decided to "Nand erase All" and then it would not even boot. I finally found a Root66, the phone came up fine but I had no connection to Verizon with or without the 4g chip. I looked through the phone settings and found that under the "Baseband Version" it said unknown. Since then I have tried flashing in with other roms. Right now its flashed with KIES_HOME_I605VRAMC3_I605VZWAMC3_1098177_REV04_user_low_ship.tar.
Its still says the Baseband Version is Unknown and the only thing that works is the wifi.
Please HELP!!!
Click to expand...
Click to collapse
I think your EFS has been messed up..what you should do is backup your current EFS even though it's highly damaged.... find a way to recover your EFS search on XDA ..EFS repair or EFS recover if all fails flash a genuine stock ROM and retry the repair or rebuild of the EFS... also as it's a demo phone...there could be other complications..I'm not sure.

seems like damaged efs.. if you had backed up the efs,just try flashing older modem. but if you never back up the efs,it will be very difficult..i suggest you to read all the threads about restoring efs and hope you can fix it.

Solution
darcy6901 said:
A few days ago I purchased a Verizon Galaxy Note 2 off of Craigslist. When the guy brought it to me I was able to test the phone with my 4G chip. It was able to make calls and access the internet. Once I got home I noticed that the phone would constantly go into a Demo mode and erase any changes that I had made to the phone. Instead of calling the guy that sold me the phone I decided I would just go ahead and root it.
The first attempt at rooting the phone ended up as a disaster. It was constantly rebooting after the splash screen. I later found that this was an easy fix. I had decided to "Nand erase All" and then it would not even boot. I finally found a Root66, the phone came up fine but I had no connection to Verizon with or without the 4g chip. I looked through the phone settings and found that under the "Baseband Version" it said unknown. Since then I have tried flashing in with other roms. Right now its flashed with KIES_HOME_I605VRAMC3_I605VZWAMC3_1098177_REV04_user_low_ship.tar.
Its still says the Baseband Version is Unknown and the only thing that works is the wifi.
Please HELP!!!
Click to expand...
Click to collapse
http://forum.xda-developers.com/showthread.php?t=2392632 This thread should definitely help you. There are all possible ways you can restore your EFS done by @tamirda . I just got my baseband version back on my Note II International GT 7100.

HELP! Having a bunch of connectivity issues.

Hey guys, i'm having a bunch of connectivity issues, all revolving around cell service. WiFi works greats. First issue is that text message get sent and received sporadically(meaning sometimes i send texts and they send right away, while other times they fail and require a few resends). Second issue is incoming calls not reaching my device(doesn't even ring on my phone) and going straight to voicemail after 2 rings/outgoings calls not ringing at all. Last and hopefully least, data seems to drop or hang on upload after a few minutes of use. Now all these issues occur sporadically and at seemingly random times, but it seems like once one of these 3 issues occur, they all get triggered.
I've checked and reset APN settings and they seem correct, although instead of "Not Set" for the username, there is "none" and there is a four digit password that has been censored by *, and for Server there is one digit *.
I've called T-MO customer service and their suggestion to solving it was a Master Reset, which is essentially a Factory Reset including wiping the Internal SD card. I've yet to do this, but i have tried a regular Factory Reset from TWRP, but the issue still persists. Not sure what to do at this point, was considering ODIN'ing back to stock(4.1.1 root66 to be exact).
If it matters, I'm running Dandroid 4.1.2, with DLJA baseband and stock kernel. Sometimes rebooting or flipping airplane mode on/off fixes it for a couple more minutes.
Any insight or suggestion would be GREATLY appreciated. Thanks for taking the time to read this.

I had this problem on my Nexus 5 and it seems to be sorted out now. But I'd highly recommend ODINing to the latest stock if you change your baseband radio and you're still experiencing the same issue. (I'm also a T-Mobile customer)
Also, I recommend heading to the market and downloading Offline SIM APN Database to verify you have the entirely correct APN.

Hey, thanks for the swift reply. Firstly, i checked the offline sim database and my APN settings match those, so hopefully APN settings are out of the question. And by latest, are you referring to 4.3? Also, i don't think i've ever flashed a radio/modem of any kind, and my baseband has been DLJA since i first bought this phone ~1 year ago.

I believe so that 4.3 is latest.

Before flashing 4.3, make sure you Sim unlock the phone first.
It sounds to me like its probably one of the following causing your issues....
Bad SIM card
Network problems on T-Mobile's end
Corrupted firmware or data
Or just part of the actual hardware going bad
(Listed what I think is most likely first)
Go to a T-Mobile store and ask an employee if they can test your device with their sim, or better yet, since its random ask if they can just replace yours.
Call T-Mobile to ask if there are any known problems in your area. If not ask if they can reset your account.
Flashing firmware with Odin (not mobile odin) can help determine if it may be a hw or sw problem. I do recommend factory resetting with stock recovery though. This actually formats /data, where custom recoveries just selectively delete things.
If its still giving problems after all of the above, its a pretty good chance some piece of hw has gone bad.

Thanks the replies guys, I'll report back with some results. Just wanna add, I've tried my sister's S4 LTE Sim on my phone and the issue still seems to occur regardless.
Sent from my SGH-T999 using Tapatalk 4

TheKucho said:
Hey guys, i'm having a bunch of connectivity issues, all revolving around cell service. WiFi works greats. First issue is that text message get sent and received sporadically(meaning sometimes i send texts and they send right away, while other times they fail and require a few resends). Second issue is incoming calls not reaching my device(doesn't even ring on my phone) and going straight to voicemail after 2 rings/outgoings calls not ringing at all. Last and hopefully least, data seems to drop or hang on upload after a few minutes of use. Now all these issues occur sporadically and at seemingly random times, but it seems like once one of these 3 issues occur, they all get triggered.
I've checked and reset APN settings and they seem correct, although instead of "Not Set" for the username, there is "none" and there is a four digit password that has been censored by *, and for Server there is one digit *.
I've called T-MO customer service and their suggestion to solving it was a Master Reset, which is essentially a Factory Reset including wiping the Internal SD card. I've yet to do this, but i have tried a regular Factory Reset from TWRP, but the issue still persists. Not sure what to do at this point, was considering ODIN'ing back to stock(4.1.1 root66 to be exact).
If it matters, I'm running Dandroid 4.1.2, with DLJA baseband and stock kernel. Sometimes rebooting or flipping airplane mode on/off fixes it for a couple more minutes.
Any insight or suggestion would be GREATLY appreciated. Thanks for taking the time to read this.
Click to expand...
Click to collapse
Funny that I came across this. I was experiencing (seemingly) the exact same problem very recently. I even picked up a new SIM card, but that didn't fix it. I was beginning to fear it was hardware related. But like Doc suggested, I used ODIN to flash stock fw, and all is well again. It appears that my problem was related to data corruption. Thought I'd post to confirm returning to stock via ODIN fixed the issue for me - in case it happens to anyone else.

Ditamae said:
Funny that I came across this. I was experiencing (seemingly) the exact same problem very recently. I even picked up a new SIM card, but that didn't fix it. I was beginning to fear it was hardware related. But like Doc suggested, I used ODIN to flash stock fw, and all is well again. It appears that my problem was related to data corruption. Thought I'd post to confirm returning to stock via ODIN fixed the issue for me - in case it happens to anyone else.
Click to expand...
Click to collapse
Thanks for the reply! Unfortunately I'm still experiencing this problem. May I ask which Android version you ODIN'd? If 4.3, MJC or NC2? I've ODIN'd two firmwares, 4.1.1 LJA and 4.1.2 MD5. I've held back on doing 4.3 because I know after that, there is no way back. But if that fixes the issue, I'm all in. Thanks!
Sent from my SGH-T999 using Tapatalk 4

TheKucho said:
Thanks for the reply! Unfortunately I'm still experiencing this problem. May I ask which Android version you ODIN'd? If 4.3, MJC or NC2? I've ODIN'd two firmwares, 4.1.1 LJA and 4.1.2 MD5. I've held back on doing 4.3 because I know after that, there is no way back. But if that fixes the issue, I'm all in. Thanks!
Sent from my SGH-T999 using Tapatalk 4
Click to expand...
Click to collapse
I used UVDLJA 4.1.1, and so far I'm free of the connection issue. I feel the same as you... don't want to flash 4.3 without being able to downgrade. I picked the LJA fw because that's what my phone shipped with, and the radio/bootloader combo always worked well for me. Sorry it hasn't worked for you! Maybe a stupid question, but did you factory reset after ODIN flashing?
Out of curiosity, did the issue resurface while you were still running stock fw? Or had you changed ROMs?

Ditamae said:
I used UVDLJA 4.1.1, and so far I'm free of the connection issue. I feel the same as you... don't want to flash 4.3 without being able to downgrade. I picked the LJA fw because that's what my phone shipped with, and the radio/bootloader combo always worked well for me. Sorry it hasn't worked for you! Maybe a stupid question, but did you factory reset after ODIN flashing?
Out of curiosity, did the issue resurface while you were still running stock fw? Or had you changed ROMs?
Click to expand...
Click to collapse
Yeah, I've factory reset from the stock recovery and had everything wiped. Well first the issue initiallly surfaced on the Dandroid 4.1.2 ROM, but I had ran that ROM for close to a year without any issues, then all of a sudden it happened. I ODINd the 4.1.1 and factory reset and at first I thought it worked but a few minutes later, the problem resurfaced, so to answer your question, yeah it still happened on stock fw. I may try it again just in case I take it in to a T-Mobile store.
Sent from my SGH-T999 using Tapatalk 4

Well since you ruled out the SIM card already, the 2nd part I mentioned would be my next suspect. (Network problems on T-Mobile's end. )
Is there any way you can get maybe 5-10 miles away from your usual locations and test there? (Remember to reboot after making it to a new location). If its still giving problems there, its very unlikely to be a tower problem. (Still possible, but very unlikely. ) Also, call T-Mobile support and ask if they can perform a reset on your account. (Can't remember what they call it exactly, but they should be able to take some sort of similar action on your account from their end.)
Finally, if you are still running 4.1.2 or 4.1.1 firmware, you can try flashing the different modems I have in my baseband thread. (Stickied in development). I can't remember right now if the 4.3 modems will work on the older firmware, but its ok to try them all. Once you update to 4.3 you can no longer use the older modems.
If, after all of that, you still are having trouble, you can pretty much rule out network problems. It'd still be a possibility, but only a very unlikely one.
After this, you might want to seriously consider flashing the MJC firmware, then NC2 if necessary. If none of that is helping I don't think there will be much more you can really do....