Chosen Solution
Just finished a battery swap in a 12-inch Retina MacBook 2015 and now I’m hearing an electric whine come from the computer whenever I wake it from sleep. Is there something I should do with it to prevent that? I don’t recall that sound at all from before the replacement.
Sadly the inductor within the logic board, you’ll need to find someone with the deeper skills to isolate out which one and hopefully replace it. Otherwise you’ll need a new logic board. Just make sure the connectors are fully seated is all you can check.
