Late 2007 MacBook Pro Randomly Shuts Down

[bricehulse]

I have a late 2007 15-inch MacBook Pro (A1226). It has a 2.20 GHz Core 2 Duo, 5 GB of memory (a stock 1 GB stick and a 3rd party 4 GB stick), and a stock 200 GB 7200 RPM Hitachi hard drive. I have had issues with it shutting down in certain situations.

(1) The laptop shuts down abruptly whenever I pick it up and walk around with it. This consistently happens within 5 seconds of picking it up. I know for a fact that this never used to be problem. I only started noticing this happening about 5 months ago.

(2) The laptop randomly shuts down abruptly when I'm using it on a hard stable surface that does not block any vents. This does not necessarily happen when it is under a heavy load. When it happens, the laptop suddenly shuts down and the screen suddenly goes black. I have to wait about 5 to 10 minutes for it to be willing to turn back on again. This happens one to three times a day, and it is completely unpredictable. Below is a graph of various temperatures up until the point when it shuts down. None of these temperatures are high enough for me to suspect that this issue is caused by overheating.

I would really appreciate it if anyone had any insight into why these random shutdowns are happening. Thanks!

 

[thundersteele]

With this model, I would bet on a failing graphics card (the usual 8600GT problem). Essentially this means you should start saving up for a new laptop.

The hard drive is the other possible suspect, due to the machine shutting down upon movement.

I think you can run the Apple hardware check, the graphics card bug shows up there usually.

 

[Gav2k]

It's your sudden motion sensor.

Google how to disable it and see if your issue persists after.

 

[bricehulse]

With this model, I would bet on a failing graphics card (the usual 8600GT problem). Essentially this means you should start saving up for a new laptop.

The hard drive is the other possible suspect, due to the machine shutting down upon movement.

I think you can run the Apple hardware check, the graphics card bug shows up there usually.

Thanks for the advice. Three years ago, the GPU completely failed and just showed static on the screen, but I took it to the genius bar and they replaced the whole logic board for free. I guess that I will have to choose between buying a new logic board or buying one of the updated MacBook Pros I expect they'll announce at WWDC.

It's your sudden motion sensor.

Google how to disable it and see if your issue persists after.

Thanks! I'll try disabling it.

 

[bricehulse]

Okay, so I disabled the sudden motion sensor, but that did not resolve the problem.

I also ran the 3-minute Apple Hardware Check, and it detected no problems. Tomorrow, I will run the hour-long version and report back.

Also, I am planning on replacing my hard drive with an SDD soon, so maybe that will solve this problem.

Thanks for all your help!

 

[bricehulse]

I disabled the sudden motion sensor, and that made no difference. I also ran the extended Apple Hardware Test, and it detected no troubles. Any other ideas?