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When moving my macbook it sometimes switch off unexpectedly (black screen) and switch on again after several seconds.

I remember solving the problem several month ago by changing a internal MacOS X settings with such a command:

defaults write

This command disabled the automatic shock detection system that prevent hard drive damage.

Does someone knows this command? a better alternative?

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up vote 1 down vote accepted

Disable the Sudden Motion Sensor to avoid the harddrive heads parking them due to loud noise in a club.

To check if Sudden Motion Sensor is activated, use the following command and look for the sms setting (1 = enabled) :

# sudo pmset -g

To disable Sudden Motion Sensor, use the following command :

# sudo pmset -a sms 0

To enable Sudden Motion Sensor, use the following command :

# sudo pmset -a sms 1


Hope this helps!

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thank you for that but I have one question: what is the first line for : sudo pmset -g ? – Martin Delille Feb 8 '13 at 14:25
I found by myself : this is to check the current value. – Martin Delille Feb 8 '13 at 14:27
I edit your answer for further reading. – Martin Delille Feb 8 '13 at 14:30

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