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.
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:
This eliminates some of the possible explanations above. The ones that remain are:
Regarding the question this thread was about (is there a way to figure out if 4G/LTE is broken)
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