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Apple's mainstream 2021 iPhone was released on September 24th and comes with a 6.1" OLED display, a dual 12 MP camera system, and in five available colors. Successor to the iPhone 12.

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Weird NFC issue *Complex?*

I would really appreciate if anyone can help me out as this issue seems bizarre to me and something I have never encountered.

NFC only works on iPhone 13 when the display is lifted from housing. Once the top portion of the display is clipped in, NFC no longer functions! Like the display is a barrier to the signal?

History: the phone has had a housing replacement which includes wireless charging flex. I have tried swapping genuine NFC flex (near camera) same issue. Not a motherboard issue as installed it into complete phone and works fine. To me this seems like a housing issue? Can a housing be faulty? And other things it can be? I have scratches the metal connections where the flex is attached to the housing for better conductivity. Still nothing.

The original housing has spot welded metal extensions which touch with the metal part on the NFC flex, on the replacement this isn't present.

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I can confirm that the third party housing was the issue. NFC problems fixed with replacement housing 🙂

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I would check the NFC antenna is not shorting to the case in some way or the aperture the signal needs to pass is blocked (think Faraday cage)

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I believe the whole point of the antenna is to ground itself to the case and be on contact with as much metal as possible to amplify it's signal? I have also tried a different screen as there are little contacts that attach to the frame transmitting signal but no result...

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@iphonerepairtom - grounding nullifies the signal! Give this a read Faraday Cage either surrounding the emission or shorting it out cancels the signal. Unlike the other antennas, NFC uses a tunnel design to limit its spread outward. Here’s more on the design NFC Antenna Design Made Easy

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Thanks Dan, so it's the other way around. I don't want to make a metal to metal connection with the NFC flex as that nullifies the signal?

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@iphonerepairtom - This is a bit tricky! The emissive area of the antenna needs to be exposed so the signal can come in or out into the open air. But there is a shield that surrounds the antenna lead (not shorting it out) think how your cable antenna lead is a COAX cable surrounding the antenna wire (shielding it) not touching it. Even in fiber optic’s we do the same making a reflective surface to contain the light the length of the distance!

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I understand! Have you had issues with this before? I have done lots of housing spaws before and never had this issue. I do the same procedure every time. The NFC is not broken as I have tried a replacement part and it works when the display is lifted from the housing. Once the display is closed NFC stops working. I have an identical phone that I've done the same procedure on and everything functions well. Could it be a faulty housing?

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