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i was going to replace the lightning connector flex cable in my iphone 8 plus. I follow the steps in the guide and finished step 64, but i had to stop. The next step is to remove the lightning connector flex cable. I then follow the guide and put everything back. After i put back everything and boot up the phone, the wifi will not turn on, it does not let me toggle. I have double checked the bottom antenna and the top antenna, all seems to look fine. Please, can you suggest where i could have forgot a connector. thanks.
Unfortunately this is not an antenna issue. If your Wi-Fi is greyed out there is a problem with your Wi-Fi IC on your logic board. This is not an easy repair and will have to be completed by a competent microsolderer that also has access to an IPhone 8 NAND programmer in case the Wi-Fi chip cannot be reballed and has to be replaced.