Chosen Solution

I was given an iPhone 8 to repair that was smashed on the front and the back, as well as having the frame bent. Long story short, I transferred the parts into an aftermarket frame (with glass and wireless charging coil pre-installed) and installed a new screen. Everything is working brilliantly (iOS 12.1) until today when I tried using Apple Pay to make a purchase. I had gone through the setup with my bank card and it shows in the Wallet, but doesn’t come up when I hold my phone up to the reader. I just opened it up again and disconnected the battery and reseated the connector for the charging coil. I’m going to try again at a different shop but I was wondering if anyone has experienced this? Could it just be a faulty NFC antenna in the coil?

Turns out it was a faulty NFC/Wireless Charging coil. The flex ribbon that extends from the coil and connects to the logic board actually came off the coil. Looks like the solder points for the pads was pretty weak.

It’s possible you have a defective housing…most of the antennas are directly embedded in the housing. In previous iPhones, there was obvious NFC coil but there was a tiny flex that had to be properly connected at the top left hand corner of the logic board. The iPhone 8 does away with this but generally speaking, antenna issues are usually related to either a bad or damaged housing or a screw done wrong in the antenna areas. The large coil, while called an NFC coil is almost certainly not for NFC transactions but for charging.

Try again at a different store. It could have been a problem on their end, not your end.