I have the same problem. I've tried antenna replacement, sim reader replacement, pcb flex replacement. I have not tried a new charging/ main board flex this is my next theory to try (waiting on part delivery). If main board flex does not fix my next theory is that the main flex connector on motherboard might be "loose", customer had damaged original screen in the same area as main board connector. Would need to resolder or replace and solder main board flex connector. If that is not successful I may have to replace band width ic chip. Note I've also tried rooting and going back to earlier software version, did not work after un-rooting phone on previous software versions.
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I have the same problem. I've tried antenna replacement, sim reader replacement, pcb flex replacement. I have not tried a new charging/ main board flex this is my next theory to try (waiting on part delivery). If main board flex does not fix my next theory is that the main flex connector on motherboard might be "loose", customer had damaged original screen in the same area as main board connector. Would need to resolder or replace and solder main board flex connector. If that is not successful I may have to replace band width ic chip. Note I've also tried going back to earlier software version, did not work on previous software versions.
I have the same problem. I've tried antenna replacement, sim reader replacement, pcb flex replacement. I have not tried a new charging/ main board flex this is my next theory to try (waiting on part delivery). If main board flex does not fix my next theory is that the main flex connector on motherboard might be "loose", customer had damaged original screen in the same area as main board connector. Would need to resolder or replace and solder main board flex connector. If that is not successful I may have to replace band width ic chip. Note I've also tried rooting and going back to earlier software version, did not work after un-rooting phone on previous software versions.