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My device won’t start without charger. With a charger connected, it auto boots and shuts off with the Apple logo and loading bar upto 30%. This continues in a loop. Diagnostics with D say battery not detected. I had a burning smell come out of the DC port last when it worked fine and the charging port used to get extremely hot. I have bought a new charger and tried.
Sounds like you needed to replace the MacBook Pro 15" Retina (Late 2013-Mid 2015) MagSafe 2 DC-In Board as it likely melted enough to distort the plastic insulator plate. Its a bit of work as you’ll need to lift the logic board out following this guide MacBook Pro 15" Retina Display Mid 2015 Logic Board Replacement. Follow it down to step 39. You may need a new battery as well! MacBook Pro 15" Retina Display Mid 2015 Battery Replacement
