Changing network to 2G

When is 4G network available, the phone goes in 2G (maybe it is due part time wrong signal for seconds, but not going back in 3G or 4G) and stay there. Now it is for few days after newest update.

HARDWARE: xperia xa2 plus
REGRESSION: by predecessor OS it happens sometimes, not so often


When is 4G network available, the phone goes in 2G (maybe it is due part time wrong signal for seconds, but not going back in 3G or 4G) and stay there. Now it is for few days after newest update.


wrong network signal for some time



when the strenght of signal is enough for 3G or 4G, the phone changes the network for this level


the phone stays in 2G



What does this mean? Do you mean “weak”?

Sailfish OS has no influence over this, or at least much less than your operator and modem firmware has.

And for completeness; even though my phone sometimes switches down too - i’m not getting stuck.

No weak. The phone stay in 2G mode in area, where is 4G. It is the problem of sailfish os. Because when I change in the settings “mobile network” 4G (it’s set to this option) → 3G and then from 3G → 4G, the network change for 4G (data rate vie mobile network is faster again). But only for some time - then it changes to 2G and stay there

Still don’t get what you are trying to say.

All this does is to tell the modem that - and you can’t seriously expect the OS to be changing this setting back and forth randomly/opportunistically.

Oj, you are in area where 4G is available. In your phone you have set preferred network 4G. But your phone remains in 2G. Do you think it is operator problem? No other people phones stay in 2G. It could be hardware problem with phone, but the phone can work in 4G (just change setting to 3G or 2G and then back to 4G and the phone works in correct network without problem till you’re in worse covered area). I think it is OS fault.

@janopalo, what did you choose in Settings => Mobile network => SIMn => Network mode?

In my SFOS, only 3 options are available:

  • Prefer 4G
  • Prefer 3G
  • 2G only

Are you saying this setting is changing all by itself, without user input?

I have “prefer 4G”, but on the screen is written sometimes 2G, sometimes 3G, also there, where is 4G available

The setting defines the highest network level the phone connects to. If you prefer 4G, phone tries to establish 4G connection. If this fails for whatever reason, it tries 3G. If not possible for whatever reason, it tries 2G.

With setting it to 3G or 2G you can prevent the phone to connect to higher network level and so save power and battery time. You can choose a compromise between data speed and battery time before next charge.

No difference why 4G fails, because there is really no network available or establishing connection fails for other reasons like SFOS bug.

Now I’m abroad, roaming, I’m in house with lower signal. Out of house is 4G, inside 3G or 2G. But sometimes I lose signal and the phone doesn’t return to the network, it stays witout signal (in time I’m writing this post, the phone doesn’t have signal, but I’m sitting on sofa, where I have almost 3G before). The phone is set to prefer 4G, I try to change the settings, but without success. The only way is to reboot the phone to get the network.

Maybe Ofono Log -app would give you (or someone else in this forum) more information about what is happening with your modem/network. By default it logs ton of stuff, so hopefully someone could help you with the proper categories to filter unneeded stuff out?

I can confirm this problem, the phone sits on 2G but after restart it will happily establish 4G connection with full signal bar despite being in the same place. This goes on for some time until it drops to 2G again.

It seems to me (just by observing the behaviour, I haven’t analysed any logs etc.) that if 4G connection is not successful for some time after downgrade to 2G it stops trying.

(Side note: this is in Germany where carriers will do all kinds of weird stuff and connections are in general quite unreliable)

I wouldn’t consider German networks less reliable than the average mobile networks in other countries (except for Swisscom, maybe). It’s rather that Germans in general tend to feel like betrayed victims and are quite strong in whining but not in improving things:)

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Well, it’s of course anecdotal evidence, but I’ve used mobile networks all over Europe and nowhere have I hit so many weird behaviours as in Germany.

As an example, my everyday struggle, SIM1, foreign, roaming on Telekom, has full signal, SIM2, local, also Telekom meanwhile loses signal completely :slight_smile:

I have also never before experienced so frequent downgrades to 2G, this is why I’ve hit the problem described in this thread in the first place.

Mh. Sounds rather like inconsistent Telekom network coverage resulting in the foreign sim roaming on other networks but the local sim switching to 2G. I also always had the impression that the network coverage abroad was better than in Germany - until I left touristical hotspots and experienced not only fringe but no coverage at all - e g. in Italy :slight_smile:
It’s like the hospitals of neighboring cities which are always presumed to be better than your local ones:-)

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When I go into the basement mobile network consistently downgrades to 2G, but always comes back to 4G when I leave it.

If the latter doesn’t happen I suspect some quirk on the provider’s side.

Commercial OSs (incl. Android) throw a lot of manpower at addressing all those quirks, so you can’t really say “it Just Works on Android”.

I’ve experienced a lot of times on my 10 the issue that after a call I get no signal and need to wait or to reboot the device to get it back

Yeah, that’s a known IMHO separate issue for X10. Usually it takes half a minute on mine. Sometimes even longer. I don’t remember if I ever had to reboot for that reason.

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I don’t have a solution or a tip as to what the problem could be, sorry.
My: Xperia 10 III/4G preferred/Operator 4ka/Slovakia.
Since my operator does not have full coverage, it uses Orange roaming. It hasn’t caused me any major problems so far. I confirm that sometimes it also happens to me that the GSM signal strength indicator and the data transmission protocol indicator completely drop out, I have no signal - 2G, 2.5G, 3G or 4G is not displayed. Then it won’t help me to wait for the phone’s communication with the network to fix itself. I have to restart the device (soft restart of services in utilities does not help). Since it doesn’t happen to me often (max. 1-2 times a month), I learned to live with it. I don’t know if it’s a fault on the side of the phone or the GSM operator. Switching from 4G to 3G, 2.5G and vice versa usually works fine for me without any problems.

I am german and feel a bit insulted by the comments, nevertheless when I was in a rather remote spot in Portugal I had perfect 4G coverage, even in a train to nowhere. Here in munich I struggle to send sms with Vodafone on 2G. I can confirm my XA2 degrading to 2G while 4G coverage is available. Almost constantly throughout the day, ofono restart helps sometimes, reboot more often. 4G worked fine on my old Xperia, though. I can provide logs or sth. if anybody has more insight on this topic.

There are simply areas where you CAN get 4G for an area of 2 square meters and move beyond that it drops. At my parents in law, If I go to the terrace, I can get 4G. If I move behind the house or INTO THE HOUS it drops to 2.5. If I go to one of the neighbors, and don’t move around a lot, I can get 4G without change. Until I move. It’s very flaky coverage there and all users (Iphones, android, me) on different providers have the same experience. Is it possible it’s just this kind of ‘zone’?