Sudden Motion Sensor - Can't deactivate

[zaciek]

Hi, i have big problem with Sudden Motion Sensor (SMS) its impossible to deactivate it.

I've used commands from http://support.apple.com/kb/HT1934?viewlocale=en_US

Snow Leopard 10.6.2, MBPro 15.4" 2.66 Mid 2009

Always sms has value -1, i cant set it to 0 (turn off)
here is terminal log:

MBPro:~ mo$ sudo pmset -g
Password:
Active Profiles:
Battery Power		-1
AC Power		-1*
Currently in use:
MBPro:~ mo$ sudo pmset -a sms 0
MBPro:~ mo$ sudo pmset -g
Active Profiles:
Battery Power		-1
AC Power		-1*
Currently in use:
MBPro:~ mo$ sudo pmset -a sms 1
MBPro:~ mo$ sudo pmset -g
Active Profiles:
Battery Power		-1
AC Power		-1*
Currently in use:
MBPro:~ mo$ sudo pmset -a sms 0
MBPro:~ mo$ sudo pmset -g
Active Profiles:
Battery Power		-1
AC Power		-1*
Currently in use:
MBPro:~ mo$

Any ideas?

 

[gr8tfly]

The "-1" simply means the battery and ac profiles are "custom".

It doesn't look like you're getting a list of settings with the "-g" switch. Try it without "sudo" (you don't need root to examine the settings - only to change them; though it should work either way.)

"man pmset" for more info on using "pmset".

I'm curious as to why you are turning the SMS off. If it's because of using a hard drive with its own sensor, you don't have to worry about a conflict with the ubMBP. I believe that conflict was quite a while ago, and only on a particular model of MacBook. I have a WD Scorpio Black with drop sensor running perfectly on my 17" ubMBP Early 2009.

 

[miker2209]

I was just wondering, i got the mid-09 uMBP and the SMS is making those click sounds everytime i move it abit.
If i was to turn off the SMS with this "sudo pmset -a sms 0" would it damage the HDD without the SMS parking the HDD?

 

[gr8tfly]

I was just wondering, i got the mid-09 uMBP and the SMS is making those click sounds everytime i move it abit.
If i was to turn off the SMS with this "sudo pmset -a sms 0" would it damage the HDD without the SMS parking the HDD?

It could. If you're moving the machine rapidly enough to trip the SMS, I'd say be more gentle with the machine. The drive is designed to withstand some g's while operating, but less is better - again, especially if you are inducing enough acceleration to trip the SMS and park the heads.

If the drive has it's own sensor, then disabling the Mac's SMS might not change the behavior (I'm sure they have different thresholds, but at some point both would command a head-park.)