SSD as second hard drive, now CPU fan isn't working?

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SSD as second hard drive, now CPU fan isn't working?

Warranty issues aside, I recently installed an OWC 115GB Mercury EXTREME Pro SSD as a second hard drive in my 27/i5 Mid 2010 2.8GHz iMac. I did not change any other configuration setting and the original hard drive is configured as shipped. After shutting everything up the internal fan(s) spin extremely loud (especially on the left/cpu side as you are facing the screen). I installed istat pro and while the temperatures look good to me, it says the CPU fan is not running. I've been searching online for days and can't find anyone else that has the same problem. I've taken the iMac apart twice since the problem started and can't find anything broken, connected upside down, or plugged into the wrong spot. Has anyone by chance run into this before? Thanks for the help! I posted a copy of the istat readings below.

iMac, Mac OS X (10.6.7), Mid 2010, 27 i5 2.8GHz, 16GB RAM

Posted on May 2, 2011 10:15 PM

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Answer 1

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Eric Ross

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May 2, 2011 10:53 PM in response to Matt 23

Run Apple Hardware Test (AHT) to check your system, To run AHT start your computer while pressing the "D" key. This should give you some information on what going on in your system.

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Answer 2

Matt 23 Author

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May 2, 2011 11:10 PM in response to Eric Ross

Thanks for the idea. I ran that (along with resetting all the power settings) and found the following hardware error which I'm now trying to find online:

4MOT/4/40000002:CPU-0

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Answer 3

Jun 14, 2011 8:22 AM in response to Matt 23

Hey,

I heard something about this problem with 2009/2010 imacs: putting in harddrives by your self causes problems with the fan (spinning at full speed all the time), because they are using special harddrives that have a heat sensor built in. without this built in heatsensor, the system doesnt know the temperature of the hardware and runs the fan full throttle just to be sure it doesnt get to hot.

i only have a german source for this though: http://www.macnews.de/mac/imac-2011-festplatte-lasst-sich-dank-proprietarer-appl e-firmware-nicht-austauschen-173448

According to that source there are two ways to fix the problem: eather you use a harddrive that carries a built in heat sensor, or you put in an externel heatsensor.

aaah: just found an english source:

http://blog.macsales.com/10146-apple-further-restricts-upgrade-options-on-new-im acs

this should be your issue. i hope i could help!

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Answer 4

Jul 9, 2011 3:05 PM in response to Matt 23

Hey Matt,

Did you find an answer to this? I think I ran into the same exact thing this weekend. I installed an SSD in the optical bay. I applied the temp sensor from the optical drive onto my SSD, but I also swapped out my main hard disk for a 3TB sata drive. The heat sensor doesn't work there, so I did have the issue with the fans spinning up, but I also ran into an issue where the CPU fan doesn't run. I got the same exact error in the hardware diagnostic:

4mot/4/40000002:CPU-0

I tried putting my old 1TB drive back in and reconnected the heat sensor, so all the heat sensors are the same as before. the only difference is that there is an SSD in place of the optical drive. Same error and 0 RPM on the CPU fan.

If you found any more information on what may be happening here, let me know. Thanks!

Mike

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Answer 5

Matt 23 Author

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Jul 9, 2011 6:55 PM in response to twinharbor

What did you do with the optical drive heat sensor? I read that if it's not positioned exactly right it may not work when attached to the SSD and that could trigger your cpu fan problem.

I haven't solved my problem yet, but I've given up for the moment. I put everything back like normal and the CPU fan still runs full blast so I went ahead and put the SSD back in. I have my AC running on full blast near my computer so I can't hear the CPU fan and while it's not working correctly it is cooling so I'm not that concerned at the moment. Sorry I couldn't be of more help.

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Answer 6

Jul 9, 2011 7:43 PM in response to Matt 23

didnt you read the article I linked? there they explain how you can work around that problem. if your imac is from 2011 there is no workaround ...

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Answer 7

Matt 23 Author

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Jul 9, 2011 8:46 PM in response to philippfromfrankfurt

I ready your article. My imac is from 2011. I didn't replace my hard drive, just added one so I didn't mess with any heat sensors. There are no additional port(s) to add another heat sensor for a second hard drive even if I had a compatible hard drive and wanted to. This is why I gave up.

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Answer 8

Matt 23 Author

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Jul 9, 2011 8:47 PM in response to Matt 23

And by the way, my 2010 imac still had the same problem regardless of what I did.

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