T1 MacBook WiFi IC Replacement
In the event a WiFi IC is internally shorted on a MacBook Pro with a T1 processor (2015-2017), you must replace the WiFi IC as well as the WiFi ROM and Bluetooth ROM from a matching donor board. The WiFi IC U3700, WiFi ROM U3780, and Bluetooth ROM U3770 are paired together and all 3 chips must be transferred together in order to restore WiFi Functionality.
Below I have provided images from an 820-00840-A Logic board that had a short on PP3V3_s5 inside of the U3700 WiFi IC.
If you ONLY migrate the Wifi IC U3700, the MacBook will acknowledged the presence of the WiFi IC, however, WiFi will NOT work and report NULL under System Information.
Replacement WiFI IC has to come from matching donor board, similar to SMC Replacements on older MacBooks. Do not use an iPad Air WiFi IC as it does not have the firmware provided by the WiFI ROM to properly function.
In theory, you may be able to dump the firmware of a donor WiFi ROM and Bluetooth ROM to the patient ROMs. However you still have to transfer the WiFi IC from the donor board where you would be getting the ROM dumps from, so you might as well just transfer the ROM chips instead.