This occurred randomly a month ago whilst on unrooted stock 4.3 XXUEMK9 with MJ9 baseband. The first thing I tried was replacing the sim reader which did not solve the problem. I have tried a new sim along with other sims and all are not being read. I have tried custom ROMs and different radios which has not helped, my IMEI has remained present and correct throughout so I'm ruling out a corrupt EFS. Is it likely that the motherboard has failed. I'm out of warranty and not wanting to stump up the cost of repair.
If anyone has any suggestions, I would be very grateful.
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