Although this ''could'' be an antenna problem, based on your description my inkling is that this is a board problem. The thing with nearly all iPhones X and newer (aside from the XR) is they have a dual board layout. The logic board is actually made of two separate boards sandwiched together. The bottom board contains all the components related to cellphone service, and other wireless functions. The top and bottom boars communicate via an interposer board and a heavy enough drop can break certain lines of connection between the two boards, causing a bevy a cellular issues.
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Although this ''could'' be an antenna problem, based on your description my inkling is that this is a board problem. The thing with nearly all iPhones X and newer (aside from the XR) is they have a dual board layout. The logic board is actually made of two separate boards sandwiched together. The bottom board contains all the components related to cellphone service, and other wireless functions. The top and bottom boards communicate via an interposer board and a heavy enough drop can break certain lines of connection between the two boards, causing a bevy a cellular issues.
Some additional info may help us narrow this down further. Where did the replacement housing come from? Did you transplant all the parts from the original housing? or were some already in the donor housing.
Although this ''could'' be an antenna problem, based on your description my inkling is that this is a board problem. The thing with nearly all iPhones X and newer (sside from the XR) have a dual board layout. The logic board is actually made of two separate boards sandwiched together. The bottom board contains all the components related to cellphone service, and other wireless functions. The top and bottom boars communicate via an interposer board and a heavy enough drop can break certain lines of connection between the two boards, causing a bevy a cellular issues.
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Although this ''could'' be an antenna problem, based on your description my inkling is that this is a board problem. The thing with nearly all iPhones X and newer (aside from the XR) is they have a dual board layout. The logic board is actually made of two separate boards sandwiched together. The bottom board contains all the components related to cellphone service, and other wireless functions. The top and bottom boars communicate via an interposer board and a heavy enough drop can break certain lines of connection between the two boards, causing a bevy a cellular issues.
Some additional info may help us narrow this down further. Where did the replacement housing come from? Did you transplant all the parts from the original housing? or were some already in the donor housing.
Although this ''could'' be an antenna problem, based on your description my inkling is that this is a board problem. The thing with nearly all iPhones X and newer (sside from the XR) have a dual board layout. The logic board is actually made of two separate boards sandwiched together. The bottom board contains all the components related to cellphone service, and other wireless functions. The top and bottom boars communicate via an interposer board and a heavy enough drop can break certain lines of connection between the two boards, causing a bevy a cellular issues.
Some additional info may help us narrow this down further. Where did the replacement housing come from? Did you transplant all the parts from the original housing? or were some already in the donor housing.