Broken headphone jack. Possible to replace?

Possible - but de-soldering and re-soldering logic board components is not like doing lamp cords or speaker wire.

You need special tools, solder and lots and lots of practice so as not to damage the logic board with too much heat. You could DIY remove the logic board (even that is a daunting project) and take it to a computer/small electronics repair shop and have them do it for you.

If you elect to DIY remove/replace the logic board purchase all the recommended tools (every job is easier when you have the proper tools), study the guide and notes (not just look at them) before beginning. Take pictures and make note of which screws go back where (I often stick them on sheets of paper using double sticky tape and make notes as needed).

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