Kindly I have this issue with my Note 10 plus quite a while and trying to fix it, but sadly still did not find the solution. After having N975F/DS for a year, when the phone goes to 3g network it loses the signal and gives a message no network connection. as a result, to receive calls and sms I need to stay in 2g only mode, and the data I use a wifi connection, but cannot use lte as if I got a call the phone will go to 3g, resulting unreachable message to the caller. I started to search the internet for a solution and after a long search I have concluded that I need to flush the device. I have downloaded the latest version from "sammobile" and as the country that I live in does not exist I have used the closest country. An hour ago I have finished flushing the rom of the device using odin and after getting back the phone to work, tried from auto mode (4g/3g/2g) mode to make a call, from 4g it went to 3g and the shock, same issue cannot connect to the 3g network. I have tried the sim card in another phone and it worked smoothly with no issues, and as well I have tried another sim card from a normally working phone in this phone and the issue exists. Kindly I need help.

For last two months or so, the situation in my two years old international HTC One X is that the data is not connecting when it is on 3g network but it is working absolutely fine with 2g network. when its connected to 3g, the mobile network fluctuates, data works with 3g speed for only few minutes and signal drops out. In simple terms, on 3g it fluctuates in data access and network access whereas on 2g it works absolutely fine. I have changed two 3g enabled sim of different carriers they are also performing the same way in my HTC one x. I have changed the location of the phone, the problem persists. My sim also works fine with another handset in 3g as well as in 2g. So the conclusion is that there is fault with my HTC one x but the question remains what is the fault. Whether software or hardware. I have also done the factory reset but to no avail and I have also switched to custom rom but the problem is still there. Any solution would be of great help.

I want to forcibly enable 3G mode on a dual-SIM Micromax Canvas A1 (Android One) running Android 5.1 Lollipop. I've already searched the net for answers, but all I came up with was using \*#\*#4636#\*#\* which unfortunately is disabled by the manufacturer. So what else can I do to force 3G?

Sometimes it's desirable to use a device on a carrier that does not officially sell it. Often this is due to regional differences and travel (for example, using a US phone in Europe) but also because some carriers simply do not offer phones that other carriers do. How can I determine if it's possible to use my phone on a different carrier, and which carriers it is compatible with? ----- *This community wiki is intended to be a canonical answer to a common question. If you feel that improvements could be made then please edit the post(s).*

I have Samsung S5 Active. It seems that it never get the 3G signal, only 2G. After some research I found that 850Mhz is disabled in my phone, I tried to enabled it with the code: *#197328640# but no luck. This code seems to work only with S5 but not with S5 Active. I don't have even DEBUG SCREEN menu if I enter this code. Any suggestion how can I enable 850 3G in my phone? I also tried to connect to my phone from terminal: $ adb shell shell@android:/ $ am start -n com.android.settings/.BandMode After entering these commands, I got to the menu in my phone: Set GSM/UMTS Band: but there were no options to chose. I believe somehting is blocking me from changing the band. Please help, I can't use 3G until I fix it, it seems that mine other chinese phone works much better than Samsung S5 Active.

I have Moto G (2nd gen) with 3G connection. During my office hours I am constantly conncted to my 3G network and when I am to my home I connect to my WiFi network. I have noticed this unusual behavior for past 2-3 weeks. When I go home and connect to my home WiFi network many notifications start showing up - like notifications from apps like MakeMyTrip/Flipkart/Yatra and more. These notifications do not show up on my 3G network. It seems these **pending** notifications only show up when connected to WiFi. Notifications for apps like WhatsApp/Twitter work fine of 3G network. What would be the reason for this and where I should be looking if I want to resolve this issue?

I have read that 2G uses less battery than 4G LTE, especially if I don't need much data. Some sources : https://www.uswitch.com/mobiles/guides/how-can-i-make-my-phone-battery-last-longer/ https://android.stackexchange.com/questions/160490/does-4g-consume-more-battery-than-3g-if-i-dont-use-it-for-data https://www.telecomhall.net/t/why-lte-4g-drains-battery-faster-than-2g-3g/138 Now, my question is : if I switch mobile data off, has the "mobile network" setting (2G/3G/4G) still an impact on battery consumption ? The reason behind this question is that I am looking for the most battery-efficient configuration in my use case. Most of the time I am connected through Wi-Fi. Mobile data is switched off. Now, as for the mobile network setting, is there some kind of optimization to be done ? I'm hesitating between 2 settings : - The default setting is 4G with VoLTE on - Or would it be more battery efficient to switch VoLTE off, and activate 2G ?

I'm going to buy an Android phone which has unfortunately blocked 4G calls by the operator. Only 3G calling will be possible. I think it's enough for voice, but: Since I travel a lot, is the 3G network available everywhere when 4G is? Or is it completely different technology so I might end up in the places where only 4G signals are available, but no 3G?

(My phone is rooted and runs Android 5.1) How can one change the DNS addresses of mobile data (and persistently, if possible) without the requirement of an app?

I understand that the colour of the signal indicator tells me whether or not I've got a connection to Google servers or not , but what is the "H" that sometimes pops up? Usually my indicator says "3G": But, in addition to having an "H" now and again, sometimes it has no letters at all: I assume this is telling something about what kind of data network I'm on, or not on, but what exactly is happening?

In the past I could connect to a proxy by entering the proxy's settings in the APN settings or Wireless settings. However, now android seems to ignore my set proxy - after hitting Save it disconnects from 3G for a few seconds (I have no internet access), and then it connects again as usual. To check it I also set a fake proxy (fake address/port) and it doesn't fail to connect - it just ignores my settings. I have Android 5.0.2, so I tried to find some info about lollipop having this issue but with no luck. Maybe someone can confirm it, or has some sort of a solution?

**Situation** - I have a Fairphone 2. I recently installed Lineage OS 17.1 - I have a UK phone provider. - I am in Germany for the next few weeks. - I am not able to connect to German networks with 4G (that worked in the past and with the same contract when I was there the last time, before I installed Lineage OS) - Instead it falls back to 3G and only stays connected for 5 minutes or so, then kicks me out. So mobile data practically does not work. - In the UK, mobile data did work. I am not sure if it also fell back to 3G or if it did continue to use 4G after I installed Lineage. I cannot simply go back to the UK and check. - I bought a local German prepaid SIM. It does connect to 3G, but not to 4G. It also regularly loses connection on 3G, especially when I'm indoors, but it stays connected most of the time, though only to 3G - I know very little about how to debug Android-like OSes. To me it feels like being told to cross a busy road blindfolded: Everything is needlessly complicated, you can't see what's going on, and anything you do will probably end in failure. - I would be happy if I somehow had mobile internet, preferrably reliably and preferrably with 4G. But failing that, 3G is also fine until they phase it out next year, if it works reliably (which it doesn't). - I have switched the preferred network to 4G in the settings. - I tried switching to 3G; it doesn't change anything. - I tried rebooting the phone (the only trick I know for Android-like OSes where I cannot see what's going on); that doesn't change anything either. **Question** Since 4G never worked with neither SIM card since I tried to understand what's going on (i.e. since I am in Germany and discovered that mobile data did not work any more), my only working hypothesis is that 4G is broken in my setup. How can I test if this is actually the case? **Alternative possibilities include:** - German providers don't like UK contracts any more and refuse to provide roaming services (because of Brexit and everything) - German providers do not like Lineage OS (or the other way around) - German providers do not like FP2 (or the other way around) - I am not smart enough to work with the kind of software Google has cooked up (Android like OSes) to figure out how to make it work with German networks - I somehow randomly always have terrible phone connection (although this does not affect the people around me) - My FP2 is somehow broken (and magically broke exactly when I crossed into Germany) - Any number of other increasingly unlikely possibilities... # Update (6 weeks later) **Additional Facts** - I observed that I do occasionally - very rarely - get 4G/LTE. So from the technical side it should work. - I tried 2 different German prepaid cards (Vodafone, O2) over the past weeks, both contracts should have enabled 4G/LTE. Almost always, I only get EDGE/3G (or a light version of 3G? It feels like in the 1990s.). - I asked the salespersons in the Vodafone/O27Telekom shops. When they did not try to sell me random stuff, they were trying to be helpful. However, none of them had an explanation or could solve the problem. - I updated my Lineage occasionally. No change. - I cannot simply flash stock Android again. I only have this one phone and I am relying on the parts of it that do actually work and cannot afford to break it. - According to this source , German providers use LTE Bands 1 (2100MHz), 3 (1800MHz) for Cities, 7 (2600MHz) for cities, 20 (800MHz) especially for the countryside. Occasionally Bands 8 (900MHz) and 28 (700MHz) are also used, but this is limited to certain providers or regions. FP2 can only do Bands 3, 7, 20 according to acejavelin's comment. This eliminates some of the possible explanations above. The ones that remain are: - German providers do not like FP2 - German providers do not like Lineage - My Phone is broken - My installation is broken - German providers downgrade non-privileged contracts (foreign and prepaid) to 3G/EDGE, rendering them essentially unusable. - FP2 only supports LTE Bands 3 (1800 MHz), 7 (2600 MHz), 20 (800 MHz) (acejavelin's suggestion), German providers may be using another Band since recently? **Regarding the question this thread was about (is there a way to figure out if 4G/LTE is broken)** - I assume the lack of answers means: No, there is not. If anything does not work, the cause has to be inferred from creatively designing experiments to rule out possible explanations one by one. E.g. installing stock Android and checking if 4G/LTE works there (acejavelin's suggestion).

Having two 4G capable sims -from truely two different operators (no virtual carriers at all)- and a Dual Active sim phone (Zenfone 2 Laser), I want to do true load balancing with a 1 sim + 1 sim 4G/3G data links configuration. However, all I can find when googling is about Dual-Carrier -or Dual-Band (HSDPA++, LTE)-, which is clearly not what I'm trying to do since it's just combining two same operator frequencies to boost speeds. The approach is like the "speedify" tool, but instead of mixing 4G and WiFi, I only want to mix the 3G/4G sims. So, the question is: Do someone know how to achieve that on Android ? By the way, is this automatically managed in Android, or is it driver/kernel/modem (e.g. Qualcomm X10, X12 hardware/firmware, etc) dependant or do I have to enable something manually ? Any information about that is ok too :) If possible, the best scenario would be having twice the Dual-Band enabled. This means a Dual Carrier + Dual Carrier configuration, for a total of 4 bands from two totally different operators.

re.: How to enable video calls on Android smartphone ? In pre Android times it was easy to make video call on a standard phone, featuring small screen. Today video call functionality is not supported by most of makes, models of Android smartphones, for unknown reason. Ok, you need to establish 3G/ LTE data conectivity for video streaming as extra add-on- communication channel. Ok, I have 3G data transfer enabled and still no support for making video calls. I am not interested in third party video calling apps. I am aware, few smartphones by Samsung support video calling functionality. Is it due to licencing or for another reason. If video calling was supported by default 10 years ago and promoted at Barcelona Mobile Congress, so why today video calling in Android smartphones is not supported or disabled by 99% default. I read a lot on this subject on the Internet but all I need is to have video calling enabled in my smartphones and I can pay extra fee. Let me know your opinion and solution ( not interested in third party apps supporting 3G video calling) thank you BTW I was told (need to test it first) that Samsung 3G video calling enabled smartphone can video call my smartphone to enable 3G video calling on-the-fly, showing camera icon to click to pick up a call. If this is the case, so in theory, any Android smartphone can support 3G video calling ( 3G connection established and paid by third party) BTW2 I read related questions and answers one asked 8 years ago https://android.stackexchange.com/questions/10092/questions-regarding-receiving-3g-calls-on-my-ideos another asked 3 years ago https://android.stackexchange.com/questions/172824/how-to-video-call and still clear why no 3G video calling support on newer Android smartphones, since what is claimed: \ " what you are looking for is the operator backed 3G-324M solution that is available on most 3G phones (not including iPhone or Android). "

I have a Moto Z2 Play with Android 8.0.0, about 3 years old. Whenever I go out of range of 4g (to 3g), the battery goes from 100% to 80 or 70 in a couple minutes and then to single digits very quickly and the phone shuts down. The phone will not turn back on in this state. When I charge it, it returns to 70/80 immediately and it will turn back on. This never happens in 4g. What is the problem? Is the battery just faulty? --- follow up --- I attached a power bank and went out. Here is what happened. It lasted longer, perhaps an hour and then went to single digits and then turned off. I then restarted the phone with the power bank and it was quickly back up to full power. What does this tell us?

I use Samsung Galaxy A5 (2015) and I have just upgraded the firmware to Android 6.0 (Marshmallow). The phone supports 3G but the option to set it is LTE/3G/2G (auto connect) on Network mode. How do I get the phone to use 3G only?

My provider has special 4G only bundles at more GB/$ but has no VoLTE support, I was looking for a solution to block mobile data when and after i get a call or for other reasons when I drop to 3G/H+. It opens the taps on my balance when it sits on H+ and i have only one solution for now is to block out my calls which isn't a very great solution. any help to this is highly appreciated

[In Android's source code, I see](https://android.googlesource.com/platform/hardware/ril/+/master/include/telephony/ril.h) typedef enum { PREF_NET_TYPE_GSM_WCDMA = 0, /* GSM/WCDMA (WCDMA preferred) */ PREF_NET_TYPE_GSM_ONLY = 1, /* GSM only */ PREF_NET_TYPE_WCDMA = 2, /* WCDMA */ PREF_NET_TYPE_GSM_WCDMA_AUTO = 3, /* GSM/WCDMA (auto mode, according to PRL) */ PREF_NET_TYPE_CDMA_EVDO_AUTO = 4, /* CDMA and EvDo (auto mode, according to PRL) */ PREF_NET_TYPE_CDMA_ONLY = 5, /* CDMA only */ PREF_NET_TYPE_EVDO_ONLY = 6, /* EvDo only */ PREF_NET_TYPE_GSM_WCDMA_CDMA_EVDO_AUTO = 7, /* GSM/WCDMA, CDMA, and EvDo (auto mode, according to PRL) */ PREF_NET_TYPE_LTE_CDMA_EVDO = 8, /* LTE, CDMA and EvDo */ PREF_NET_TYPE_LTE_GSM_WCDMA = 9, /* LTE, GSM/WCDMA */ PREF_NET_TYPE_LTE_CMDA_EVDO_GSM_WCDMA = 10, /* LTE, CDMA, EvDo, GSM/WCDMA */ PREF_NET_TYPE_LTE_ONLY = 11, /* LTE only */ PREF_NET_TYPE_LTE_WCDMA = 12, /* LTE/WCDMA */ PREF_NET_TYPE_TD_SCDMA_ONLY = 13, /* TD-SCDMA only */ PREF_NET_TYPE_TD_SCDMA_WCDMA = 14, /* TD-SCDMA and WCDMA */ PREF_NET_TYPE_TD_SCDMA_LTE = 15, /* TD-SCDMA and LTE */ PREF_NET_TYPE_TD_SCDMA_GSM = 16, /* TD-SCDMA and GSM */ PREF_NET_TYPE_TD_SCDMA_GSM_LTE = 17, /* TD-SCDMA,GSM and LTE */ PREF_NET_TYPE_TD_SCDMA_GSM_WCDMA = 18, /* TD-SCDMA, GSM/WCDMA */ PREF_NET_TYPE_TD_SCDMA_WCDMA_LTE = 19, /* TD-SCDMA, WCDMA and LTE */ PREF_NET_TYPE_TD_SCDMA_GSM_WCDMA_LTE = 20, /* TD-SCDMA, GSM/WCDMA and LTE */ PREF_NET_TYPE_TD_SCDMA_GSM_WCDMA_CDMA_EVDO_AUTO = 21, /* TD-SCDMA, GSM/WCDMA, CDMA and EvDo */ PREF_NET_TYPE_TD_SCDMA_LTE_CDMA_EVDO_GSM_WCDMA = 22 /* TD-SCDMA, LTE, CDMA, EvDo GSM/WCDMA */ } RIL_PreferredNetworkType; The problem is, I don't know what the terminology maps to. "LTE" is obviously just 4G LTE, but what are TD-SCDMA, WCDMA, and EvDo? I'm assuming at least some of them must map to 2G (GPRS), 2G (EDGE), 3G, "3.9G" (HSPA+), but which is which? And which ones are actually CDMA (Sprint, Verizon, etc.) rather than GSM? (I'm a little confused because it seems GSM LTE phones also have modes like WCDMA?)

I have an old Android phone with Ice Cream Sandwich and DroidWall as a firewall, which makes sure that apps can't use the 3G unless I enable it for that app. DroidWall starts on boot but there is a very brief time before it starts when any app can use the internet. What I would like to do is stop all incoming and outgoing internet access until DroidWall automatically runs on boot to put the firewall rules in place. DroidWall allows running a script when it starts so conceivably I could undo the block-everything rules when it starts. The phone is rooted but doesn't have a /etc/init.d/. Basically I want to make sure there is not even a second that traffic can get out before the firewall. 3G is expensive but I need it so I can't turn it off.

How can I configure an unlocked HTC Desire for 3g connectivity in Peru? I have managed to add an APN so that I have EDGE but I would like to use Claro's 3.5g. I also have an iPhone with the same kind of dataplan that has 3g pre-configured so I am hoping that it is possible. I realize that this is a very specific question but I can´t get any worse help than at the Claro office...