Breaking Band: Tri-band LTE / eCSFB issues thread

[denali]

eCFSB appears to have went live in Chattanooga, TN (37403, 37409).  On my Nexus 5, I have to lock my phone into 3G mode in order to receive SMS and voicemail notifications.

 

I've also noticed that when I'm in LTE mode on my phone, Sensorly won't do a download test, but will do an upload and ping test.

[moeSizlak]

Interesting, thanks for the info.

 

Here's what I'm seeing with my HTC One M8 in Buffalo, NY:  I have a very strong LTE signal at both my home and my work, and most points in between.  All towers at home, work, and in between are at least 3G accepted.  Upon booting the phone, it will happily connect to LTE and stay connected.  If I drive for a while, to home or to work, it will switch to 3G and *never* switch back, ever.  Even if I drive back to where I started from (where I had a strong and consistent LTE connection).  

 

The only way the phone will EVER connect to LTE again is if I either reboot it, or toggle airplane mode on and off.

 

I am very frustrated and don't know if it is the phone, or an eCSFB issue, or what...

 

 

it's an eCSFB issue as you stated. My tower by be would do the same on my ONE max from November2013 till like maybe 3 weeks ago I had consistent tower irregularities due to that. Nothing is wrong with the phone. Sprint will just get to it optimize it when they can... So put it in your head it won't be fixed to July and go about your business. In the mean time u will have have to toggle the connection to keep it on if u don't lose it or hand off while in the same area.

 

The new radio firmware that came with the 1.54 update completely fixed this for me.

[Beremat]

The HTC One Max is a Sprint Spark (therefore tri-band) device that doesn't do simulaneous 1x/LTE... it's therefore a device that uses eCSFB, right?

 

If I'm right, then the problem belongs here... otherwise, please let me know where I should post it... thanks!

 

 

My One Max has really strange behavior when connected to LTE which leads me to believe that it's having ECSFB problems. The reason I'm saying this is because I have non-triband devices to test with which I can ensure are connected to the same tower under the same conditions.

 

In my room, I get LTE 1900 (UCF/DCF 1912.5/1992.5 says Signalcheck) at around ~-95dBm. The signal fluctuates if I move around the room, but the lowest I can get it to go is -105dBm (which is in my closet). Even then, I don't experience losing signal and the phone disconnecting from LTE.

 

However, when using this, I have several issues:

• SMS and MMS never come in and are never sent
• Ping fluctuates up to 6000ms
• Download speed slows to ~800kbps (very consistent) and once it drops, it doesn't improve until airplane mode is toggled (probably an unrelated issue?)
• Occasionally, downloads and uploads both stop. However, the phone still says it's connected to LTE, but I get a notification that says "Could not connect to mobile data connection." (or something similar.) During this time, I cannot receive calls, I cannot sent or receive messages, and cannot use data whatsoever. After 10-15 seconds, everything suddenly starts working again.

The reason I'm suspecting it's eCSFB is because a regular HTC One (M7) and a Galaxy S3 work flawlessly for hours without a single hiccup.

 

Thoughts?

[zodiac12345]

The HTC One Max is a Sprint Spark (therefore tri-band) device that doesn't do simulaneous 1x/LTE... it's therefore a device that uses eCSFB, right?

 

If I'm right, then the problem belongs here... otherwise, please let me know where I should post it... thanks!

 

 

My One Max has really strange behavior when connected to LTE which leads me to believe that it's having ECSFB problems. The reason I'm saying this is because I have non-triband devices to test with which I can ensure are connected to the same tower under the same conditions.

 

In my room, I get LTE 1900 (UCF/DCF 1912.5/1992.5 says Signalcheck) at around ~-95dBm. The signal fluctuates if I move around the room, but the lowest I can get it to go is -105dBm (which is in my closet). Even then, I don't experience losing signal and the phone disconnecting from LTE.

 

However, when using this, I have several issues:

• SMS and MMS never come in and are never sent
• Ping fluctuates up to 6000ms
• Download speed slows to ~800kbps (very consistent) and once it drops, it doesn't improve until airplane mode is toggled (probably an unrelated issue?)
• Occasionally, downloads and uploads both stop. However, the phone still says it's connected to LTE, but I get a notification that says "Could not connect to mobile data connection." (or something similar.) During this time, I cannot receive calls, I cannot sent or receive messages, and cannot use data whatsoever. After 10-15 seconds, everything suddenly starts working again.

The reason I'm suspecting it's eCSFB is because a regular HTC One (M7) and a Galaxy S3 work flawlessly for hours without a single hiccup.

 

Thoughts?

 

Of the issues you specified, ONLY the SMS/MMS are CSFB related. All the other issues you experience shouldn't be happening. Ping and slow data are not CSFB related at all, I can't see how they could be related to CSFB. When you get the latter error message, it is because of an authentication problem between the handset and the network, again, CSFB is not related. 

 

I know this doesn't sound like a simple fix, but you will need to call and complain to Sprint. Texting is CSFB related, however data/pings are not. And a word of advice, when you do call, do NOT mention CSFB or any jargon that you yourself wouldn't understand if you didn't go on this site. The average Sprint Rep isn't tech savvy enough to know the difference between triband and single band. 

[EvanA]

Of the issues you specified, ONLY the SMS/MMS are CSFB related. All the other issues you experience shouldn't be happening. Ping and slow data are not CSFB related at all, I can't see how they could be related to CSFB. When you get the latter error message, it is because of an authentication problem between the handset and the network, again, CSFB is not related.

 

I know this doesn't sound like a simple fix, but you will need to call and complain to Sprint. Texting is CSFB related, however data/pings are not. And a word of advice, when you do call, do NOT mention CSFB or any jargon that you yourself wouldn't understand if you didn't go on this site. The average Sprint Rep isn't tech savvy enough to know the difference between triband and single band.

SMS/MMS is handled over LTE so that's not related to CSFB issues. It doesn't sound like CSFB issues because the phone wouldn't be connecting to LTE at all if that were the case. This seems to just be a problem with the tower or defective device.

 

Sent from my Nexus 7 using Tapatalk

 

 

[zodiac12345]

SMS/MMS is handled over LTE so that's not related to CSFB issues. It doesn't sound like CSFB issues because the phone wouldn't be connecting to LTE at all if that were the case. This seems to just be a problem with the tower or defective device.

 

Sent from my Nexus 7 using Tapatalk

 

Trust me when I say SMS/MMS is CSFB related. I bought the HTC One Max a week after launch, and could not send or receive texts on LTE at my home, granted it was Band 41 instead of 25. When I set it to 3G mode, texts went through fine. However now, texts go through fine over LTE at home because the CSFB issue was fixed. I posted this problem in an earlier thread and everyone came to the consensus it was CSFB related.

 

Edit: I meant to quote EvanA, but I'm doing this from my phone rather than desktop and I seem to have screwed up with that part.

 

 

Edit 2: Quoted EvanA

[Beremat]

Trust me when I say SMS/MMS is CSFB related. I bought the HTC One Max a week after launch, and could not send or receive texts on LTE at my home, granted it was Band 41 instead of 25. When I set it to 3G mode, texts went through fine. However now, texts go through fine over LTE at home because the CSFB issue was fixed. I posted this problem in an earlier thread and everyone came to the consensus it was CSFB related.

 

Exactly, setting the phone to CDMA only mode instantly fixes SMS and call issues. Will call in and let them know something's wrong.

Edited April 11, 2014 by Beremat

[iansltx]

Looks like the issue has spread to Austin as well (x-post alert):

 

http://s4gru.com/index.php?/topic/5709-lg-google-nexus-5-users-thread/?p=306448

[kojitsari]

What work on a tower would cause ecsfb issues(turning on 800 and etc, not the obvious stuff like equipment upgrades and such)? I haven't been able to get 3g in the few areas where I can't get LTE, unless I force evdo only mode, for the past few days. I'm thinking its ecsfb related because after I switch back from evdo only it'll hold onto the signal for a bit and them drop it for 1x(this is an -85dbm signal with about -5dbm fluctuation either way), and signalcheck occasionally shows evdo/ehrpd being scanned and registering for a second at about the same signal levels on my n5 but it doesn't connect and goes back to 1x.

 

Sent from my Nexus 5 using Tapatalk

[iansltx]

eCSFB appears to be fixed now on the tower near me. LTE speeds are back to where they should be, and I'm not getting the signal-searching issues that I was before. So that's good.

[leozno1]

Not sure if this is a eCSFB issue but when I set my HTC One M8's Network Mode to "CDMA Only" it refuses to connect to 3G at all. But when set to the default "LTE/CDMA" it connects to 3G just fine.

[mikejeep]

Not sure if this is a eCSFB issue but when I set my HTC One M8's Network Mode to "CDMA Only" it refuses to connect to 3G at all. But when set to the default "LTE/CDMA" it connects to 3G just fine.

"CDMA Only" on that screen translates to "1X Only", so if you mean you can't connect to EV-DO/eHRPD, that is working as intended.

 

Misunderstood which screen we were talking about, my bad!

 

-Mike

[transitwatch889]

So I was thinking that my HTC One max was having CSFB issues but after switching back to my Nexus I'm not so sure because if that was the case I would be having LTE only mode and I'm actually having full service the bility to send and receive text and I'm be leaving now that makes you see one max me just simply be faulty its been like this for more than a few days now. unfortunately I don't have insurance on it so what's my next course of action in this case I'm wondering.

[leozno1]

"CDMA Only" on that screen translates to "1X Only", so if you mean you can't connect to EV-DO/eHRPD, that is working as intended.

 

-Mike

 

But I've never had an issue with that on any of my previous devices. When I would set it to CDMA only, it would simply retain 3G and refrain from scanning or attempting to connect to LTE. I used to do this to preserve battery life in places where I am barely able to get LTE and my phone is constantly bouncing back and forth between 3G and LTE. 

 

However I did dial ##72786# in the dialer and reset the radios and it's working again. Must have been an issue during the Hands Free Activation when I purchased the device.

[mikejeep]

But I've never had an issue with that on any of my previous devices. When I would set it to CDMA only, it would simply retain 3G and refrain from scanning or attempting to connect to LTE. I used to do this to preserve battery life in places where I am barely able to get LTE and my phone is constantly bouncing back and forth between 3G and LTE. 

 

However I did dial ##72786# in the dialer and reset the radios and it's working again. Must have been an issue during the Hands Free Activation when I purchased the device.

 

Ahh I think we are talking about two different screens. You're probably referring to the Mobile Networks screen on the Settings menu. I thought you were referring to the Phone/radio info screen accessible through a dialer code, which also has a "CDMA only" setting. We're both right..

 

-Mike

[mikejeep]

So I was thinking that my HTC One max was having CSFB issues but after switching back to my Nexus I'm not so sure because if that was the case I would be having LTE only mode and I'm actually having full service the bility to send and receive text and I'm be leaving now that makes you see one max me just simply be faulty its been like this for more than a few days now. unfortunately I don't have insurance on it so what's my next course of action in this case I'm wondering.

 

There could be network upgrades in your area that are causing temporary issues, but if you are referring to a Nexus 5 working fine, that is probably not the cause. If you're referring to another (non tri-band) Nexus, you're comparing apples and oranges, because CSFB issues would not affect that.

 

You don't need insurance if your device is defective; it is still covered by a warranty. You should contact Sprint if you think it is your phone; they will likely ask you to do a factory reset to see if that resolves it, so you might want to try that first to see if it resolves anything.

 

-Mike

[tampaflusa]

Could a phone connecting to B26 cause a csfb issue. In other words does csfb have to be enabled on all band? For example, if a tower has all bands broadcasting but csfb is only on band 25 and Band 41, not Band 26 cause your phone to be knocked to 3G if it picks up the Band 26? I found this very issue here in Tampa in a area that I pick up band 25 and 41. I started having a issue where my LTE connection would switch and stay on 3G like it does with towers that don't have csfb correctly enabled. So I suspected before it had to do with band 26 because it would briefly connect or scan band 26 before dropping to 3G. Well I disabled Band 26 and that did the trick, it connected to band 25 and Band 41 with no problems.

Here is the proof it did connect to band 26 briefly.

 

 

Sent from my SPH-L720T using Tapatalk

[kyle_4thousand]

Handset: Nexus 5 & G2

 

LTE Connectivity: None since 4/26

 

Location: Orlando, FL 32816

 

Note: Experiencing issues with a newly 4G accepted tower- I'm assuming issues should get worked out rather soon since Orlando doesn't seem to have many problems with eCSFB. Anyone have experiences with a new B25 tower coming on line that has had similar issues?

[flyloc2]

Are all 3g/4g towers CSFB enabled?  My wife's HTC One M8 can't send or receive text and it can't get on the internet.  However, at home and other locations it works fine.  Two of the three towers by her job are accepted 3g/4g, but one isn't even 3g accepted.

[Tajustin95]

Man in San Jose still having ecsfb issues. Can't connect to lte . 3g only. Q_Q

[JonnygATL]

Is there a rough timeline on when these issues will be largely resolved on Sprint's network?  I'm patient but it's annoying having essentially gone back to a 3G phone (at least until these ecsfb issues are resolved).  

[mikejeep]

Is there a rough timeline on when these issues will be largely resolved on Sprint's network? I'm patient but it's annoying having essentially gone back to a 3G phone (at least until these ecsfb issues are resolved).

This has been stated to you numerous times.. the Atlanta market should not have any eCSFB issues at this point. It is one of the most complete NV 1.0 markets in the country. Have you followed any of the advice others have offered you in other threads? I do not think the network in your area is the source of your problem.

 

-Mike

[JonnygATL]

This has been stated to you numerous times.. the Atlanta market should not have any eCSFB issues at this point. It is one of the most complete NV 1.0 markets in the country. Have you followed any of the advice others have offered you in other threads? I do not think the network in your area is the source of your problem.

 

-Mike

Yeah I have and there is just no way that it's the phone (again) unless all Nexus 5 devices have LTE connection issues.  Most people say that they do not, which I find baffling (given my experience).

 

I read somewhere on these forums where a user asked if Band 26 can cause separate ecsfb issues when it is being brought online but I don't think I saw the answer to that.

 

And, yes, I'm aware that it's been said before but it really doesn't matter when I'm still experiencing the same issues.  It shouldn't be a problem BUT IT IS.  And that's why I'm keen on reading any issues people are having related to the Nexus 5 or even network issues as I continue to try to find a source for this issue.  The only thing I can think of is to just sell the Nexus and go back to Samsung but I'm trying to hold out as long as I can to see if the issue resolves itself.

 

One last thing - the tower nearest my house is the only 3G only tower for miles and miles around.  But it IS 3G upgraded, just not 4G.  This was no issue for my GS4 as it would pull LTE from other, more distant towers.  But my N5 will not, even in LTE only mode.  Other parts of town it WILL pull LTE if I force it but not here at home.  That's why I feel the RF performance isn't as good on this phone.  Everything I've experienced with this phone (both of them that I've had) directly contradicts what others are saying about this phone.  But I'm not making it up.  It's happening and it's annoying.  Otherwise why would I mention it?

[pokefan02]

Band 26 testing does cause Spark phones to drop to 3G. At least in my Ericsson market where most all 4G sites here have B26 on but not available.

 

Sent from my HTC M8

[nexgencpu]

Yeah I have and there is just no way that it's the phone (again) unless all Nexus 5 devices have LTE connection issues.  Most people say that they do not, which I find baffling (given my experience).

 

I read somewhere on these forums where a user asked if Band 26 can cause separate ecsfb issues when it is being brought online but I don't think I saw the answer to that.

 

And, yes, I'm aware that it's been said before but it really doesn't matter when I'm still experiencing the same issues.  It shouldn't be a problem BUT IT IS.  And that's why I'm keen on reading any issues people are having related to the Nexus 5 or even network issues as I continue to try to find a source for this issue.  The only thing I can think of is to just sell the Nexus and go back to Samsung but I'm trying to hold out as long as I can to see if the issue resolves itself.

 

One last thing - the tower nearest my house is the only 3G only tower for miles and miles around.  But it IS 3G upgraded, just not 4G.  This was no issue for my GS4 as it would pull LTE from other, more distant towers.  But my N5 will not, even in LTE only mode.  Other parts of town it WILL pull LTE if I force it but not here at home.  That's why I feel the RF performance isn't as good on this phone.  Everything I've experienced with this phone (both of them that I've had) directly contradicts what others are saying about this phone.  But I'm not making it up.  It's happening and it's annoying.  Otherwise why would I mention it?

I have mentioned this to you before bro (and numerous other members, Its probably B26 lacking eCSFB, just throw your phone onto LTE only mode, till the issue is resolved. 

 

And for the record, the N5's radio smokes the GS4..