Losing signal after drop, antenna connector and blue coil intact!
I dropped my iPhone 4 pretty badly a few weeks ago. The back side glass broke, a small part of the LCD became black, and the (music) speaker died. The middle metal frame also got a little bent in the down left corner.
The phone itself was however still working. I've changed the backside and the phone is usable, but one problem remain. I lose signal.
When I insert my SIM I always get reception for a short while. During this time I can text, call, and surf without problem, but then I get "No Service", and it usually stays that way until restart.
I've been searching this subject for weeks, and have come to understand that it should have something to do with the antenna connector being loose, or the blue coil missing, but both are in their place and the blue coil isn't falling of even if I push it with the tools!
Can it be the antenna cable itself, or does anyone have a clue what it might be? I am very, very thankful to person that figures this out!
I'm having the same problem with mine after being stood on, only my problem is the missing blue coil inductor. What info I have gathered this past few days is this.
If you havent already, check the speaker block the antenna is attached to, the cable off that should click firmly into a plug right near the battery clip, if that isnt clicking in, take a pin and check the clip isnt bent into the hole, this is a tiny component so take care with it and you may need a new one,(£3 off eBay) also, check that the antenna cable attached to the speaker block has 4 or five metal pins that should make contact with the metal casing, again if not (£3 off eBay) you can see this if you take the battery out.
If these are all fine, check your logic board is connected by a tiny gold coloured hook which is near where all your terminal clips are at the top of the phone, this also has to make a connection with the metal casing to get full signal effects, this tiny part can easily get bent while removing the logic board so go easy with it. Hope this info helps and you sort your problem.
The answer to your questions, how to fix the blue inductor coil causing a signal problem, the solution is easy we have repaired many with a 100% success rate. If you look at the signal antenna which you plug the cable into, simply run a wire from the left side bridge it to the right side point on the blue coil and follow it all the way to the furthest (right) component on the top left side. This will act as a 'bypass route' and your signal will start to work again.
All it takes is a bit of micro-soldering knowledge and some 0.1mm wire and basing soldering equipment. This will fix your problem guaranteed, providing it was the missing blue coil that caused your signal issue in the first place.