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Question: 13" non-Retina MacBook Pro locked up again

It happened before a couple of years ago, although it was slightly different. Back then I plugged in what I knew was not an MFi Lightning cable and everything just went dead in a split second. The charge light started flickering green/orange before it went completely dark. Nothing worked. The battery status button wouldn't do anything. Couldn't power up, power down, even trying SMC reset. I could hear a faint hum coming from the board, although the hard drive wasn't spinning and the fan stopped immediately. I took it to an Apple Store without an appointment and was told that I could come back in the morning to get on the non-reservation waiting list. I gave up, looked up how the memory or drive are replaced, and followed the instructions for how to disconnect the battery connector. When I reconnected it I could power it up and it never happened again.


Until today when something similar happened. This time I plugged in a MFi Lightning cable with my iPad Mini 4 attached and everything just went dark. I've got an SSD now so it wasn't like the previous time where I could tell the drive was no longer spinning. I didn't hear any noise, but my first impression was that I should take off the bottom cover and disconnect the power again. And this time it was pretty warm and I could kind of smell it, if anyone here is familiar with what a circuit board smells like when it gets hot. I pulled off the battery connector and let it cool down for a few minutes before I reconnected. And it fired up immediately with the power button.


So - any idea of what happened? I'm familiar with certain electronic issues like latch-up, but I'm not sure if that happened here. I've described this as somewhat of an intermediate state where it can't power down and can't power up unless power is completely removed. I've heard about users with similar conditions, and some would just wait for the battery to die, charge it, then it would recover. There seem to be a few people reporting similar conditions on the newer MBPs, but those of course aren't as user-serviceable as a Unibody MBP.

MacBook Pro 13", macOS 10.14

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Jul 20, 2019 5:48 PM in response to y_p_w In response to y_p_w

Don't put too much faith in "that smell" <what a circuit board smells like when it gets hot> because it is very similar to the smell of the DUST that accumulates in there.


On a Mac Pro desktop, to Reset the SMC (which is involved in fans, power, and charging) you remove the AC power and wait a bit.


So what you did (disconnecting the battery for a bit) effects an SMC Reset. That should set everything right unless something is fried.


The more intriguing question is whether the standard "Hold the four keys" for SMC Reset approach would have done as well, or whether disconnecting the battery is sort of a "Super Reset".

Jul 20, 2019 5:48 PM

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Jul 20, 2019 5:50 PM in response to Grant Bennet-Alder In response to Grant Bennet-Alder

Grant Bennet-Alder wrote:
Don't put too much faith in "that smell" <what a circuit board smells like when it gets hot> because it is very similar to the smell of the DUST that accumulates in there.

On a Mac Pro desktop, to Reset the SMC (which is involved in fans, power, and charging) you remove the AC power and wait a bit.

So what you did (disconnecting the battery for a bit) effects an SMC Reset. That should set everything right unless something is fried.


I understand that one can still do an old-fashioned SMC reset on a Mac desktop because there's no battery. Kind of tough to do it on a notebook since everything is connected to a battery "under the hood" these days. The keystroke style SMC reset does nothing for a locked up MBP.


But it was getting warm this time. My last lockup everything stayed reasonably cool. I wanted to disconnect the battery ASAP in case something overheated without a working fan.


I'm using it right now and the temperature seems pretty normal. I can hear the fan at least I don't have to replace this since I don't have a backup computer other than a late 2007 polycarbonate MacBook that I can't use. I'm just hoping it doesn't happen again.

Jul 20, 2019 5:50 PM

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Jul 20, 2019 5:54 PM in response to y_p_w In response to y_p_w

I guess I added my last line while you were composing:


The more intriguing question is whether the standard "Hold the four keys" for SMC Reset approach would have done as well, or whether disconnecting the battery is sort of a "Super Reset".


I think what you just said is YES, disconnecting the battery sure is a "Super Reset" !

Jul 20, 2019 5:54 PM

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Question: 13" non-Retina MacBook Pro locked up again