Samsung Galaxy S4 -- text/phone/voicemail no-connect even with bars

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Samsung Galaxy S4 -- text/phone/voicemail no-connect even with bars

Much like the end of this thread

 

https://forums.att.com/t5/Android/Samsung-galaxy-s4-SIM-card-error-post-kitkat-update/m-p/3910878#M5...

 

Last 3 weeks or so, Samsung Galaxy S4 for me and wife have sporadically not been connected, even in presence of 1-2 bars of 4G LTE. Texts don't come through, phone calls go right to voicemail, voicemail messages don't alert the user. Basically the phone acts like it's not on the network at all. This turns out to be dangerous, especially if I need to get in contact with my wife for something urgent.

 

This is not an isolated event. I'm extremely technical (semiconductor design), and colleagues with S4s have seen this occur for the last month or so.

 

AT&T will tell you to:

1.) Replace SIM card

2.) Power ON/OFF, take out battery

3.) Factory reset

4.) Download "Mark the Spot" to diagnose and report errors

5.) Report issue to customer service

6.) If all else fails, back up photos, etc., replace phone at warranty area

 

Needless to say, none of this works. Hence posting here.

 

My fellow nerds and I have instead filed a bucket of technical bugs and tried to isolate the issue. We actually found the behavior differs by tower, and when trying to file a massive bug (like corporate level) on a tower in Austin, TX, the "engineers" from AT&T took a look and said "issue has been resolved". Seems like a script kiddie ran some python tests remotely and all the tests said "PASS" so therefore it was "resolved". If they had gone to said tower in person with a phone, they would see the LTE brokeness, but alas, that's not how the support works.

 

Moving on, the issue invovles 4.4.2 and some recent LTE update. 4.4.3 has been out for some devices, but Samsung hasn't pushed it to AT&T yet.

 

If you are able to turn off LTE, everything will work fine. But how do you do that? The mighty internet says to root your phone, but what if you don't want to do that (especially with the plethora of shady ROMs out there)? The Internetz will also say to add your own "APN", but that gets hacky and is specific to your local 4G carrier (which may or may not be a derivative of the babyBell buyouts). Previous versions of AT&T S4s allowed you to turn off LTE, but that was taken away in Kitkat without root. iPhones can still do this without root.

 

So, seems options are getting limited. Solutions seem to narrow to rooting the phone, hacking a non-rooted phone to find a correct local APN for 4G, or simply dumping AT&T, paying the ETF, and going to a network which takes this seriously. (If I get asked one more time if I reset my phone or if there was sufficient battery, I'm going to scream. Did you try a new SIM card??)

 

Ultimately, replacing/rooting/updating/SIM swap/battery replacing/ON/OFF will NOT fix this issue, it is systemic. AT&T does not seem to realize this. Too bad, probably losing customers b/c of it.

 

Maybe this post will get a real "engineer" to do something besides run pre-coded diagnostics on the S4s.

 

I'll try to find a universal APN hack to 4G and post.

Message 1 of 21 (12,631 Views)
Tutor

Re: Samsung Galaxy S4 -- text/phone/voicemail no-connect even with bars

Ok, here's a start

 

http://apn-settings.com/us/att-apn-settings/

 

4G seems to work out of the box, but still defaults to LTE. Haven't tried the 3G. Bleh, want 4G without LTE.

 

Perhaps these settings will circumvent the issue. Will post if I find more.

Message 2 of 21 (12,606 Views)
Tutor

Re: Samsung Galaxy S4 -- text/phone/voicemail no-connect even with bars

APN types

 

http://forum.xda-developers.com/showthread.php?t=1685273

 

default -- the default data connection. Can't co-exist with another

mms -- multimedia messaging services -- needed for texts

supl -- Secure User Plane Location -- location services

hipri -- High Priority mobile data

fota -- Firmware over the Air -- updates (this is the only one missing from the APN link before vs my default. Not sure if this may/may-not be the issue)

 

there's one called "dun" for wifi sharing? "admin" and "internet"

 

some sites recommend listing nothing, which may default to some of them. Sounds like a pile of instability to play too much with this.

 

AT&T has a site for devs themselves.

https://developer.att.com/technical-library/apns/apn-descriptions-and-characteristics

 

Lots of info here, playing with lots of settings, good luck, won't post again until I get a real response or find a formula that is stable and actually "communicates" with my wife without fail

 

 

Message 3 of 21 (12,598 Views)
Tutor

Re: Samsung Galaxy S4 -- text/phone/voicemail no-connect even with bars

Took some time to experiment APNs, for those that care. Doesn't solve the issue, but easily gets a 2X LTE speed uplift. Goes as fast as WIFI. Odd that such trite settings can affect so much:

 

Settings-->Connections-->More networks -->Mobile networks-->Access Point Names

 

Hit the '+' in the upper right

 

Name : ATT other  (name is not relevant)

APN : phone  (other choices are broadband, etc. You want 'phone')

MMSC: http://mmsc.mobile.att.net

Multimedia message proxy : proxy.mobile.att.net

Multimedia message port : 80

MCC : 310

MNC : 410

APN type: default,supl,mms,internet

Bearer: LTE  (only if you're around towers with LTE, otherwise leave unspecified)

 

 

leave the rest blank/default

 

"hipri, fota, admin" have measureable disadvantages (ping, download/upload)

"internet" and bearer : LTE have measurable advantages

 

 

Again, neither solves the actual problem of random drop. Still have two cases open about the issue, but another two weeks, I'm dropping the network.

 

If anyone else has feedback, do tell, I'm kind of out of ideas besides rooting.

Message 4 of 21 (12,537 Views)
Contributor

Re: Samsung Galaxy S4 -- text/phone/voicemail no-connect even with bars

Thank you for posting all of this!  My wife and I have been going crazy with this exact problem.   We got our S4s in March, and they worked just fine until about a month ago.

 

We have been to 3 different AT&T stores, and the people we dealt with had no clue and acted like they had never heard of this problem.  At one of these these stores the the rep removed the battery and then plugged it back in.  At the next one, the rep gave us new sim cards.  The problem came back after each of these "fixes."  At the last AT&T store, the rep suggested that since the phones are still under warranty, we should return them and have them replaced.  I assume this replacement would be a refurbished phone which for all I know would have the same problem.  We have also gone three times to see the Samsung rep at our local Best Buy.  On the first visit, she changed our APN settings, I believe to the exact settings you have spelled out.  I don't have the phone with me at the moment, so I can't confirm that. The same malfunction was back again the next day. The next Samsung rep reflashed our software, and the problem was back after 2 days.  We went back again and saw the same rep who had changed our APN settings, and she told us all she could suggest is to go to the Samsung authorized repair center in a nearby city.  We did, and the rep there told us their protocol was to reflash the software and then if that failed, to change out the motherboard.  For this last step, they have to get approval from Samsung. We talked them out of doing the reflash since it was done a few days ago and didn't work.  So at this moment we are waiting for the approval.

 

I'd consider dumping AT&T, but when I research this problem on the internet, I am seeing people on Sprint and Verizon who have the same problem.  The consensus I'm reading among these people is that the KitKat 4.4.2 "upgrade" is not getting along on a friendly basis with a great many (but not all) S4 phones.  I am emphatically not technical-minded, so I can't give an opinion on that.

 

We are among the last people on Earth to get a smart phone (these are our first), and we have been wanting our old flip phones back.  In fact, I am pushing to revert to the old Western Electric rotary-dial that we still have in the closet.

Message 5 of 21 (12,497 Views)
Contributor

Re: Samsung Galaxy S4 -- text/phone/voicemail no-connect even with bars

I'm here in Austin with an S4 and have the same issue.  Been updating AT&T Mark the Spot and talked to AT&T reps on phone and in the stores and thus far, none have been any help.  Hoping someone can find a solution to this.

Message 6 of 21 (12,468 Views)
Tutor

Re: Samsung Galaxy S4 -- text/phone/voicemail no-connect even with bars

Thanks for the responses guys, glad I'm not going nuts as the only one seeing this. I just found some other threads experiencing the same thing.

 

Anyway, found something super hacky. "Test mode"...looks like admin access to settings and network stats in your phone.

 

In your phone dialer

*#*#4636#*#*

 

Then look in Device info. Try changing LTE/GSM auto (PRL) to GSM auto (PRL). This forces HSPA (4G) only mode without the LTE, which is my guess what's wrong. Your download speeds will go from 6Mbps to like 2Mbps, which sucks, but whatever, WiFi + working phone/texts is better than brokenness.

 

I think these settings go back to default if you reset.

 

My guess is 4.4.3 will fix all this mess. Anyway, try it out, let me know if you have success with this.

 

Message 7 of 21 (12,423 Views)
Contributor

Re: Samsung Galaxy S4 -- text/phone/voicemail no-connect even with bars

Hello, been experiencing same tech difficulties and am currently waiting on a replacement. Apparently the warranty phone will not fix this. What I am wondering is this problem limited to only s4 or is it showing up in s5 as well? My phone worked well til I got the update with the Isis wallet and other b/s from att. Thanks att. Is there any way to revert to the prior o/s without ruining the warranty? I will keep calling them for warranty phones until they fix this.

Message 8 of 21 (12,408 Views)
ACE - Master

Re: Samsung Galaxy S4 -- text/phone/voicemail no-connect even with bars

its a samsung problem on all carriers but only effects like 4% of the phones out there.   And I've read post with the s5 doing the samething

*The views and opinions expressed on this forum are purely my own. Any product claim, statistic, quote, or other representation about a product or service should be verified with the manufacturer, provider, or party.
Message 9 of 21 (12,405 Views)
Tutor

Re: Samsung Galaxy S4 -- text/phone/voicemail no-connect even with bars


MoarDots wrote:

In your phone dialer

*#*#4636#*#*

 

Then look in Device info. Try changing LTE/GSM auto (PRL) to GSM auto (PRL). This forces HSPA (4G) only mode without the LTE, which is my guess what's wrong. Your download speeds will go from 6Mbps to like 2Mbps, which sucks, but whatever, WiFi + working phone/texts is better than brokenness.

 

I think these settings go back to default if you reset.

 

My guess is 4.4.3 will fix all this mess. Anyway, try it out, let me know if you have success with this.

 


Can confirm with my phone and wife's phone, this does indeed work. Sprint/Verison had the same problem Spring 2013 when they migrated OS's and did something to LTE (tis where the solution came from). They seemed to figure it out in 2 months. ATT is having the issue now, T-Mobile never had it. Yes, S4s and S5s.

 

Drop to 4G without LTE for the time being and wait for 4.4.3 to fix it. Or jump if that's insufficient. There's enough noise in ATT about this now, so if they ignore it, shame on them.

 

Happy hacking!

Message 10 of 21 (12,357 Views)
Contributor

Re: Samsung Galaxy S4 -- text/phone/voicemail no-connect even with bars

MoarDots, you hit the nail on the head. So hard it makes me want to scream. Thank you sir. 

 

Fellow nerd here, been lurking for months trying to find a fix. 3 S4s in this household, returned one, replaced one, did the APN crap, everything.... I know the phone is not the problem, just been patiently waiting for AT&T to put out a fix. 

 

The *#*#4636#*#* works. Did it on 2 phones. Be patient, give it a minute before the LTE sign at the top goes off and then you know it did the trick. 

 

Thank you again sir. Please procreate and fill the earth with more creatures like you. 

Message 11 of 21 (12,230 Views)
Voyager

S4 user here also guys in the OKC area. I experience this...

S4 user here also guys in the OKC area. I experience this problem 4-5 times a day and have to toggle airplane mode on/off to connect again to the network so I can make/receive calls and text messages and data. I have changed network mode to 4G and no longer experience the problem. It is clear it deals with the LTE setting and I really wish at&t would fix the problem. My tech guy has tried everything and we have come to the conclusion that it is with the 4.2 update and I hope this problem is fixed with and when the new update comes out. PLEASE READ AND FIX AT&T.
Message 13 of 21 (11,901 Views)
Contributor

Same here. Thanks for posting the info. I thought it was...

Same here. Thanks for posting the info. I thought it was just me.
Message 14 of 21 (11,875 Views)
Contributor

problems with s4 active

Have the new s4 active warranty replacement will it start not connecting after 4.4.2 update?
Message 12 of 21 (11,892 Views)
Contributor

Re: Samsung Galaxy S4 -- text/phone/voicemail no-connect even with bars

I'm assuming this only works if I actually have a network connection? I've been having the same issue that everyone else is speaking of, but now my s4 won't recognize my sim card at all, even after getting a new one from the store earlier today. So it looks like I'm stuck using my old s2 until the new update rolls out, if that ever happens.

Message 15 of 21 (11,016 Views)
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