Unexpected Shut down when moving macbook pro on my 'lap'

The platter is spinning at 5400 or 7200 RPM, withha read/write head hovering .000056 inches from the platter. You move the system, and you risk a head crash. The SMS shuts down the system to prevent the head crash.

At least put the system to sleep before moving it if you want the risk removed.

if you can SLOWLY move the macbook to your lap AND the monitor blacks out (you havent specified the exact nature of your 'switch off') then you have a mechanical fault likely in the monitor cable at the logic board or the cable itself.

I used to repair laptops and seen more than a few that would black out when squeezed just right, most were connector issues on the cable at the logic to monitor.

Test is by very slowly moving it, if you cant fault it by very slowly moving it, then its the SMS sensor

if you CAN fault it thru same, you have a mech. fault that needs repair.

😊

After having similar issues to loan007's and unsuccessfully troubleshooting up to disabling the SMS, I think it's an issue with the monitor cable; at least in my case. I plan on replacing it myself using a very thorough guide from iFixit (an immeasurably more useful site than this one). So, thank you PlontinusVeritas and others who have offered reasonable solutions to OP's problem.

I logged in to note the above, but also to note the disgustingly unproffesional quality of Linc Davis and Csound1's responses. Linc Davis' first reply was unhelpful and loan007 noted this; niether of those two facts are bad things. If someone comes to the forums for help it's a pretty reasonable assumption that they've at least thought about bringing it the Genius Bar and are looking for some alternate way to fix their issue. Most issues can be taken care of without going to the Genius Bar if one is willing to invest the time and energy into research; which could prove substantial depending on the problem.

I don't care if you're "total strangers who owe [loan007] nothing and volunteer [your] time". I wouldn't want an offer for help from a user who's only recourse is "take it to a professional"; so, please don't give it. At least offer an alternate option or explain why it is ABSOLUTELY the only answer. Otherwise don't get offended when someone labels your "help" useless. Offering reasonable criticism is not having a "bad attitude".

GRRRRRRR, Forum attitude engage!

Realised no-body has asserted wether this happens ALL the time, or just when the machine is running on battery power.

Seeing as the original query related to moving it from lap, I think it might be the case that it happens when running on battery.

Therefore, its worth checking if it is the BATTERY CONNECTOR.

This part is about £6/$9 to buy and can be replaced quite easily.

If the plastic moulding of it has worn down, it could rattle the battery at its connections to power the machine and just break power supply if moved suddenly.

Similar issue here with a MacBook Pro (13-inch, Early 2011).

- replaced HDD

- swapped for an SSD

- replaced battery

- replaced memory

- replaced harddrive cable

- set SMS to 0 (good tip btw)

- replaced magsafe connector

- replaced topcase

About to change motherboard to see if issue persists. Otherwise I'm stumped as well.

Did anyone get any where concrete with this? Seemed like a lot of unnecessary barking with a couple helpful tips thrown in here and there.

My problem is that I replaced the SuperDrive with an SSD, but I still have the HDD in the computer. It's in the same exact place. I didn't have to touch it at all to replace it so as far as I know it shouldn't be loose wire. Disabling sms did “fix” the issue though. I disabled it and literally spun my laptop around. All you guys talking about putting your laptops to sleep have never seen elementary students at a 1:1 school go to town on some MacBooks. The things I've seen those kids do!

So I turned sms back on and it shut down with just a slight motion.

has this been solved?

i had the same issue with my couple month old laptop.

based on something odd i read on another site, i realized it was a magenetic sensor issue. i have a wallet i keep my IDs in, that is in my front pocket. so as i slide the laptop away from me (not fast at all) it would shut the computer off, as it thought i had closed the lid/screen (as it has a magnet in it to let the macbook know someone has closed the screen... 🙂

not sure if this is helpful to anyone else, but this issue was re-producable, SMS was off, as i have a SSD, and happened regardless of battery power or plugged in.

thanks!

Firstly, Csound1 and that other idiot... GO AWAY!

Secondly i'm on a MacBook Pro 13' Mid 2012 with a 256gb SSD, no HD.

I'm getting roughly the same problem as MnMegaMan's having.

Basically when I hold it in one hand (Left hand to the left of trackpad), it will freeze, stutter (audio/video) and restart after roughly 20 seconds of freeze.

Anyway, my laptop used to get very hot until I recently cleaned out all the dust (USE CANNED AIR, DO NOT BLOW WITH MOUTH). Apparently according to a video I watched on youtube, someone worked out this heat had slowly bent the shape of the metal holding the RAM in place, and as that gets pushed on, it temporarily dislodges, then freezes/restarts.

It's still happening after a re-shuffle of my RAM, but I hadn't thought of the exposed wires thing, so will check soon and report back. If it is the RAM slot issue though, any suggestions?

To those with helpful answers and information, cheers. To those that went 'DUHHH I THINK IT MIGHT BE BWOKEN, YOU SHOULD GET IT FIXED.' go home.

I agree with you whole heartedly and must admit that Csound1 and Linc Davis attitude *****.

Just fyi, I looked into your problem as I had one like it myself, and found that the logic board itself shorted out. I was stumped as you were, and so I took the logic board out and held it at the sidewith minimal bend ad it shut off by itself.

To verify this I used another A1286 that is fully functional and did the same and nothing happened.

Am leaning towards reflowing the board and will let you all know what happens

determine if sudden motion sensor is issue by disabling it >

http://support.apple.com/kb/HT1935

Maybe you'll find this more helpful. Continue to use your broken computer as is.

Lincs advice was and is correct, you may not like that but it changes nothing. Your Mac needs competent diagnosis so either you figure it out or take it to Apple.