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1 iPhone searching/no signal/no carrier
Have searched the forums and the net for an answer to my problem, (apologies in advance if it has already been answered), which on the face of it is quite simple, that of "no service" I have however tried every thing I and others can think of....
First of all symptoms:
Started a few weeks ago and has gradually got worse, phone is out of warranty.
Phone toggles between "searching" and " no service".
With 3g on!no service at all.
When 3g is turned off, some times get a full 2g signal but as soon as extra power is needed when switching to 3g or opening safari signal immediatley goes.
Phone hasn't been dropped!
Have checked:
All the normal things, reset network settings, restore etc., etc., have tried sim in another phone,all ok....checked network provider (o2)to ensure not barred (unlikley).Checked and cleaned sim contacts, ensured copper aerial is contacting frame.
Have swapped logic board to ensure aerials and rest of hardware are working ok.
Conclusions.
Seems as soon as phone asks for extra power,leading me to think a component overheats/shuts down/fails. but what is this and where?
Not hardware (exception of logic board) not baseband, not os,not sim, not network,
Is this a good question?
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9 Comments
you swapped your motherboard into a working iphone and had same problems?
by pollytintop
Hello Polly...thanks for your response...swapped a logic board from another working phone into the faulty one and all worked fine which rules out aerials etc.,and can only mean logic board problem either software or hardware!
by Peter
tried cleaning the sim tray ?
by pollytintop
Yep...tried that, also gently levered up the contacts to ensure good contact.
by Peter
Going to try a new battery, but old one is still holding charge ok. It is jailbroken and unlocked but this was as an attempt to cure the problem, rather than the other way around!
by Peter
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