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I have received a xperia phone (Xperia XA1 G3121) with following problem which I want to try and resolve: While having a SIM I can make calls and have mobile data as long as I have 4G or H+ indicator on the top right corner. https://ibb.co/3YwFKVB In areas where those are unavailable (I get 3G and bars indicator) I cannot make calls nor have mobile data connection. https://ibb.co/xYRzhnc While searching the internet I came to find videos about replacing antenna cables. After removing the back I found 2 such cables (black and white): https://ibb.co/cDg9bt5 I replaced the cables thinking that might solve the problem without any success. In youtube videos I saw variant with only 1 cable and 2 cables. My intuition was that the black one is for 3G since disconnecting the other disabled my 4G signal. Given that on some networks I have data and tone and on older generation frequencies I don’t I came here seeking some advice. What can I try to isolate the problem? Later Edit: I have replaced the bottom daughterboard earlier because another defect with it was that it would not charge. At that point I did not try 3G or below calls because I couldn’t imagine not working after doing a normal call as a test. The previous daughterboard was thrown as a results. Should I suspect a flaw with the new daughetboard ? Any way to check it other than trying another replacement ? Any help you can shed is appreciated, thank-you
Hi @ray14324, I’m wondering if it is an antenna problem, because as you said, the phone is registering that it is receiving a 3G signal. Maybe it is something else Have you tried manually setting the Network Mode to GSM only in Settings > More > Mobile networks > Preferred network type? Have you verified that the APN settings are correct for each provider that you tried? Have you tried a factory restore and then checked, in case it is corrupted firmware causing the problem? (backup the phone to the cloud or a computer and also remember your Google user name and password- if necessary, before doing the reset) If it is an antenna problem then perhaps changing the board that houses the GSM antenna may be worth a try. Here’s a teardown video of the phone. At 2:45minutes into the video the BT, WiFi, GPS antenna module can be seen being removed followed by the board with the GSM antenna. Just some thoughts.
