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2012 MacBook Pro Powers on By Itself on Rough Roads

macperformanceguide.com

61–70 of 97 posts

Re: 2012 MacBook Pro Powers on By Itself on Rough Roads

#61

Earlier quoted context omitted.

"Mostly, waking the computer from sleep takes a fraction of a second but sometimes it takes ~20 seconds to show the screen." I've seen this as well, and it feels related to whether the computer is suspended to RAM (sleep) or suspended to disk (hibernate).

This is a new setting for the rMBP that hibernates to disk after something ridiculous like two hours. It drove me absolutely batshit, but thankfully you can change it to something more reasonable via a simple pmset command. (I brought mine up to 24 hours before writing to disk) It is especially bad because the behavior is a frozen cursor while it reads the RAM image off disk. SSD's are fast but on the 16Gb model it s…

Thanks for the pointer. From looking at that on my rMBP I see standbydelay set to 4200 seconds. Increasing it to 2 hours might actually work fairly well for me, as I'm not usually away from the computer for longer than that during the day.

Re: 2012 MacBook Pro Powers on By Itself on Rough Roads

#62

Interesting. In the past, an external mouse (BT or USB) was required in order for a MacBook to operate in "clamshell mode". If no such device were connected, you couldn't get the laptop to turn on. Period. This makes me wonder if there isn't a firmware bug? EDIT: An additional requirement (forgot): an external display must be attached. I'm doing some testing with my 2011 MacBook Air that is still running Lion. CORREC…

Seems like a more likely explanation is a hysteresis issue with the hardware lid sensor. It "opens" under vibration and allows the transient key events to be seen by whatever controller (my guess is that all this is preboot, so the CPU firmware isn't invoked) is listening for the wakeup events.

Basically, if the key sensors can be jiggled closed, the lid sensor can be jiggled open. And because these happen for the same reason at the same time, that's not a two-point failure mode; it's something you'd expect to happen.

Re: 2012 MacBook Pro Powers on By Itself on Rough Roads

#63
post #24
post #11

How on earth is a key being pressed on a closed laptop? Bumpy road or not.

The keys and screen are extremely close to one another when the laptop is closed. With any compression of the device, it's possible the screen could press the power button. On my 2011 MBP I use a thin fabric pad made by RadTech to prevent any screen damage from this incidental contact, and also to prevent oil from keys from contacting the screen while my device is closed.

Does this not work on the new MBPs? I use this too when travelling overland, lest you get abrasive marks on your screen over time. Its a great, simple preventive maintenance trick. That would suck. I would also hate to have turbulence on a flight set this of, and then have your battery dead when you unpack.

Re: 2012 MacBook Pro Powers on By Itself on Rough Roads

#64

I haven't seen this particular issue, but I have had a whole bunch of strange, likely firmware-related issues on my Retina. For instance, sometimes the screen just won't shut off when trying to put it to sleep - Closing the lid and the screen/logo stay lit up indefinitely. Chrome and the integrated graphics card really don't play well together - it's caused an OS reboot 10's of times in the past month. Mostly, waking…

I also have a problem with slow shutdowns. Sometimes it takes 30 seconds to shut the machine down. Much less time to boot.

Re: 2012 MacBook Pro Powers on By Itself on Rough Roads

#65
post #57

Earlier quoted context omitted.

If the laptop gets too hot in a bag, it can cause fire, so it's a potentially life-threatening bug.

No, no it can't. The battery will drain, but not much else. The temperatures you'd see wouldn't even be likely to reduce the lifetimes of components. This is inconvenient and annoying, but not life threatening. Stop being alarmist.

Fire chiefs issue warning that overheating laptops can cause fires

http://www.harrogate-news.co.uk/2012/02/24/fire-chiefs-issue...

Laptop fire blamed for Vancouver death

http://www.cbc.ca/news/canada/british-columbia/story/2009/08...

Laptop overheats, starts fire that destroys west St. Louis County home

http://www.kmov.com/news/local/Firefighters-battling-blaze-a...

Israel Police: Fatal fire in family home likely caused by overheated laptop

http://www.haaretz.com/news/national/israel-police-fatal-fir...

etc...

etc...

Re: 2012 MacBook Pro Powers on By Itself on Rough Roads

#68

Interesting. In the past, an external mouse (BT or USB) was required in order for a MacBook to operate in "clamshell mode". If no such device were connected, you couldn't get the laptop to turn on. Period. This makes me wonder if there isn't a firmware bug? EDIT: An additional requirement (forgot): an external display must be attached. I'm doing some testing with my 2011 MacBook Air that is still running Lion. CORREC…

I did some very detailed testing. I cannot wake my MacBook Air with the keyboard, regardless of condition.

https://gist.github.com/3699744

Re: 2012 MacBook Pro Powers on By Itself on Rough Roads

#70
post #62

Interesting. In the past, an external mouse (BT or USB) was required in order for a MacBook to operate in "clamshell mode". If no such device were connected, you couldn't get the laptop to turn on. Period. This makes me wonder if there isn't a firmware bug? EDIT: An additional requirement (forgot): an external display must be attached. I'm doing some testing with my 2011 MacBook Air that is still running Lion. CORREC…

Seems like a more likely explanation is a hysteresis issue with the hardware lid sensor. It "opens" under vibration and allows the transient key events to be seen by whatever controller (my guess is that all this is preboot, so the CPU firmware isn't invoked) is listening for the wakeup events. Basically, if the key sensors can be jiggled closed, the lid sensor can be jiggled open. And because these happen for the sa…

I think that's probably the most plausible explanation. It makes me wonder what kind of g-forces the laptop is encountering. Most electronics aren't intended for "rugged" environments, and "ruggedized" equipment is a lot more expensive.
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