The upper case of my (5,2) Macbook has stopped working so I'm not able to use the power button to turn it on. I'm currently using an external keyboard/mouse. Here's the problem- In order to tun it on, I have to short the power pads on the logic board which I think is pretty risky if not done properly. I wanna avoid the risk of making the mistake and frying the logic board.

under system preferences -> energy saver -> power adapter, I found "restart immediately after a power failure"

So if there is a "power failure', I should theoretically be able to turn the mac on the next time I plug in the magsafe adapter, right?

But what counts as a power failure? Is just taking the battery out while the magsafe adapter is still attached considered a power failure?


This is similar to functions found in the bios of PC's as described here. I don't believe that functions is supposed to be available on portables, but evidently it is for you.

What explicitly counts as a power failure is loss of power to the motherboard. So that means the battery would have to be removed while the MagSafe is not connected. If the MagSafe is connected, it would not count as a power failure.

The computer starts up again if the power was cut to it (Last State). So if you yank the power at the log in screen, it'll power back on however if you yank the power after shutdown, it'll stay shut down.


You are correct that those pads will be permanently damaged and you will wreck the substrate or electrostatically ruin the hardware in time. If you can write off this Mac and replace it soon I would rig up a better switch. Since you’re uncomfortable shorting the pins, I would solder a connector of your choosing to the pins and have a physical switch wired. A micro push switch might also fit somewhere inside.

The power restart on a “detected power loss” has never been reliably solid in my experience for battery powered devices. Sometimes it triggers, sometimes not and mostly when you are counting on it it fails - perhaps the SMC is designed for line powered events on iMac and mini and pro line.

The other option would be a flat rate depot repair for $300 or so. As long as no clearly unauthorized repairs have been done (or poorly done and undocumented official repairs) Apple fixes everything wrong for the flat rate or explains why the flat rate doesn’t apply. You get a 90 day warranty and hopefully several years of life for far less than a new Mac.

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