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My laptops keyboard and trackpad stopped working a long time ago but recently I’ve started using a separate keyboard and mouse for it. Today I shut down the computer without thinking and now I have no way to turn it back on! Is there anyway I can power it up without having to use the built-in keyboard and trackpad???
Here’s a picture to the power pads for your system
Just short across the two pads briefly and the system should restart. From the sounds of it your keyboard is in need of replacing. You might find replacing the uppercase to be an easier repair MacBook Pro 13" Retina (Early 2015) Upper Case Assembly (you’ll need to get the one that’s still in stock) and here’s the guide MacBook Pro 13" Retina Display Early 2015 Upper Case Replacement Here you can transfer your trackpad over and either transfer the battery or get a new one following this guide MacBook Pro 13" Retina Display Early 2015 Battery Replacement
If you disconnect the battery connector then plug in the magsafe it will start booting. You can then reconnect the battery connector.
