Chosen Solution

My little one spilled water on my MacBook Pro 13” mid-2012 (A1278, EMC2554). The logic board was visibly burned so I replaced it with another one (thank you iFixit guides!). The computer works fine now and the battery holds power too, except I cannot use the power button to switch it on. I need to unplug the battery and plug in the magsafe connector to switch it on. Rest of the keyboard works fine. Is there anyway to easily switch on the laptop without using power button? Can I use ‘Accessibility’ or some other software based wizardry to use another button as power on/off? OR can I somehow bring the battery-to-logic-board connector outside the computer so it can be easily plugged or unplugged? Not keen to open up 10 screws each time I switch it on!

Many thanks for your response. I should say I am really a novice at getting into a laptop and, having held my breath for an hour while replacing the logic board, I am really trying to avoid having to do that (and more) all over again. For now I am just going to put my laptop to sleep instead of shutting it down for as long as possible I guess. If I do muster up the courage to open the whole thing again, I will indeed consider replacing the keyboard.

Reinsert the keyboard to logic board connector. Note that it has a flip lock on it and that needs to be up when inserting the cable. I use a piece of electrical tape to pull the cable into the slot rather than trying to push it in. Once it is fully seated, push the lock down to hold it place.

I’m not keen on altering the design of the logic by wiring up an external switch and you can’t re-assign any of the other keys to do the same action via software if that is what you where thinking. The only thing I could see (I’ve never done this with a Mac) is to leverage wake on LAN ability the system has. Here’s a bit more WakeMeOnLan v1.85 I don’t know of any simple tool under iOS or macOS that does the same. Frankly, I would just bite the bullet here replacing the keyboard MacBook Pro Unibody (A1278) Keyboard or MacBook Pro 13" Unibody (Early 2011-Mid 2012) Upper Case which is a lot easier! Granted a bit more, but a lot less hassle! For either you need to get to this point MacBook Pro 13" Unibody Mid 2012 Upper Case Replacement