Mark got an iPhone 5s from a friend that had a "dog bite" in it. It will work connect via 4G, but not via 2.4GHz Wi-Fi (5 Ghz is fine). Is it worth fixing? He's tried DFU'ing it. Should he try iFixIt? Leo says he can look on iFixIt and get a teardown of the phone to see if the parts that don't work will be replaceable. Some aren't. Leo says it may be the antenna that is damaged. If he can replace the antenna or the Wi-Fi radio, then he should be OK. If it's soldered onto the circuit board, then he's out of luck. It just depends on how modular it is.
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