iMac fan running constantly

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Level 1

61 points

iMac fan running constantly

A couple of days ago, during a hot spell in my apt. (85 degrees), my iMac's fan started running constantly. Since then, the temp has become a comfy 70 degrees and I've run Disk First Aid and repaired the HD, but still, I've got a constant fan with a gentle breeze on my fingers on the keyboard. Sounds nice, but I know that's not right.

The fan (at least to my own eyes and ears) doesn't seem to be running overly fast, just constant.

Any suggestions?

Thanks in advance..
Chris

2 Ghz Intel Core Duo iMac, Mac OS X (10.5.4)

Posted on May 5, 2010 2:43 AM

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Answer 1

Top-ranking reply

Barry Hemphill

Level 8

40,468 points

May 5, 2010 4:48 AM in response to chrisnatale

Hi Chris:

The behavior may or may not be normal. You might reset the SMC:

http://support.apple.com/kb/HT3964

Barry

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Answer 2

May 5, 2010 8:11 AM in response to chrisnatale

If resetting the SMC as Barry suggests does not change this behavior, you may want to run the Apple Hardware Test that came with this iMac. Insert the install DVD into the computer, restart and hold down the D key during startup. Note any errors that come up during the test.

Best of luck.

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Answer 3

R C-R

Level 6

17,782 points

May 5, 2010 10:58 AM in response to chrisnatale

AFAIK, the fans in all Intel Macs run continuously at their minimum settings & speed up as required to regulate the temperature. Typically for iMacs, the minimum for the optical drive is the lowest, usually under 1000 rpm, & faster for the CPU & HD bay fans, for example around 1200 rpm for the 8,1 models.

If any of the fans stop completely, that would be a problem & hopefully the Mac would shut down before it overheats & that causes damage to anything.

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Answer 4

chrisnatale Author

Level 1

61 points

May 5, 2010 5:22 PM in response to Barry Hemphill

Whisper quite, now, Barry. You are, as they say, da bomb!

Thanks for the help everyone...

Chris

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Answer 5

May 5, 2010 7:18 PM in response to chrisnatale

You are most welcome, Chris.

Barry

🙂

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Answer 6

Jun 7, 2010 11:27 AM in response to laundry bleach

I ran the hardware test and got this error 4SNS/1/40000000:TAOP-130.000
Could you or anybody tell me what this could be. I am hoping I won't have to take it in to be serviced. Any insight would be appreciated. Thanks.

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Answer 7

R C-R

Level 6

17,782 points

Jun 7, 2010 5:56 PM in response to windstormreigns

windstormreigns wrote:
I ran the hardware test and got this error 4SNS/1/40000000:TAOP-130.000
Could you or anybody tell me what this could be. I am hoping I won't have to take it in to be serviced.

The error may be related to the ambient temperature sensor in your iMac. Whatever it is, it needs to be repaired if you want your iMac to operate reliably.

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