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chevy2410 Author

Level 1

5 points

21.5' iMac fan speed is to fast

Hi all,

I've got a problem with my new 21.5' iMac. According to iStat the hard drive fan is spinning way to fast. Now this has been happening at least once every 8-9 days since I got this machine about 4 weeks ago. I've been searching this forum and the net to find a solution and there doesn't seem to be any. When I called Apple last week the CSR told me that when I'm not using the comp I should shut it down. I'm sorry but that's not the solution. Has anyone heard if Apple is going to fix this issue?

Wow! As I'm typing this the fan is now increasing in fan speed. Under iStat it's saying that it's the hard drive fan that's the issue. It went from 1099rpm and it's continuing to climb in speed. It's now over 4800rpm and still climbing. In the past I've never been at the comp when it's started doing it. I did take it to a local Apple authorized repair shop and form 2 days they ran some tests and couldn't get the comps fan to reproduce the issue. The tech said he called Apple and they are not even saying there is a problem. he seems to think that at some point Apple will send a firmware update down to fix the issue. Now I've had my comp back from the repair shop for 8 days now and low and behold I had the fan problem right on schedule. What should I do? Should I call Apple again?

Thanks so much,
Chevy

21.5' Imac, Mac OS X (10.6.2)

Posted on Mar 20, 2010 10:46 AM

527 replies

Apr 17, 2010 11:43 AM in response to chevy2410

I seem to have the exact symptoms as john+apple, which are similar to others on this post. At what seems to be every 7 or 8 days, my HD fan increases from 1100 rpm to over 5000 rpm. It has happened once when I was using the computer, and two other times when the computer was idle. The only way I've found to reset it is to power the computer off and turn it back on. I just called Applecare and they suggested resetting the SMC, which I will do. I made sure the Applecare rep was aware of this post. I will also start keeping better track of the amount of days between occurrences and start logging the HD temp when this happens. I asked about the FW update discussed, and was told that was only applicable to the 27" iMac, not the 21.5". Hopefully Apple will come up with an update to fix this issue. In the meantime I'll keep following this post. I also urge anyone with this problem who hasn't called Applecare, to do so in order to keep them on top of the issue.
Thanks,
Tim

chevy2410 Author

Level 1

5 points

Apr 18, 2010 5:29 PM in response to Tim-In-WA

Resetting the SMC will not work. What you can try is to see if there is any issues with the hardware itself. Take the second disc that has the iLife stuff on it and reboot your machine with that disc in it and hold down the D key at the bong sound and you should after a couple of seconds be in the "Apple hardware Test". Check the Extended test box and then run the test. Report back with the results.

Chevy

Apr 18, 2010 7:07 PM in response to chevy2410

I ran the test recommended by Chevy with No Problem Found. Unfortunately I could not check the Extended Test box, since my magic mouse was not responding when in this mode and I tried it a couple of times. I also tried an old Windows USB mouse but that didn't work either. I was able to run the non-extended test and it did not find any problems. I was not surprised that no problems were found, so we'll see in about a week if I still have the problem with the fan kicking into high speed.
Thanks,
Tim

Apr 18, 2010 8:40 PM in response to chevy2410

Just to add to this... I have 46 iMacs that were purchased mid-December... ALL with the same problem. If they are left on for more than 7 days, the HD fan goes nuts. AHT shows no trouble found. HD temps are in range. No word as to what is causing the issue. I have been wanting to call this in to my rep, but haven't had time. I just shut the machines down on Fridays to keep the fan issue from coming up. If I can get in touch with them tomorrow, I'll pass along what I hear.

Apr 19, 2010 2:46 AM in response to Jason Reinstedler

Jason,

This is an excellent example and should make it crystal clear to Apple to look for a software/firmware issue and fix. No batch of bad components would fail on a synchronized schedule as we are seeing with this issue.

John

Apr 19, 2010 7:54 AM in response to chevy2410

Hi guys,

I just ran the hardware test and no problems were found. I couldn't run the extended because mouse was of no use. I am still having the same problem every 7 to 8 days. Thanks to all for your help in trying to resolve this issue.

Hersheys Mom

Apr 19, 2010 9:28 PM in response to chevy2410

Hi,

Another data point...I got my 21.5 iMAC on Jan 2, and it does the same thing. The fan goes high speed about every 7 to 10 days. I have done all the updates, and the machine exhibits no other problems. It has done this since it was new.

-john-

Apr 19, 2010 11:12 PM in response to chevy2410

Same iMac, same issue.

jsf4

Level 1

0 points

Apr 21, 2010 5:27 AM in response to chevy2410

Hello Everyone,

I have the same problem with my iMAC. Seemed to begin when I turned off the
computer sleep energy preference.
My wife has the same machine(3 months newer), uses the computer sleep
and does not seem to have the problem.

Any positive results on fixes from anyone.

Jerry

Apr 21, 2010 11:54 AM in response to jsf4

I have also disabled the sleep mode. Does everyone have their sleep mode turned off?

chevy2410 Author

Level 1

5 points

Apr 21, 2010 1:29 PM in response to pauvregaspard

I don't use the sleep function except to put the monitor to sleep when not in use. Otherwise the computer runs 24/7. Now regardless of weather you use sleep or not shouldn't have any impact on this issue. This is a firmware issue and I hope Apple is in the process to fix the issue.

Chevy

jsf4

Level 1

0 points

Apr 21, 2010 2:00 PM in response to chevy2410

Hello Everyone,

Well, I hope Apple is working on it as well but
I don't know if anyone has a confirmation of that.
I guess it could be a firmware problem. Chevy, how are you
so sure of that??

It would be an interesting experiment if someone put the
computer sleep preference on just about when the
7 or 8 day period is about to start. I have to wait another
week as my fan was on this morning.

As I said, my other iMac does not have this problem yet
and the preference is on.

Jerry

vazo

Level 1

8 points

Apr 21, 2010 2:29 PM in response to chevy2410

Hi,

I have the same problem. Been having it since January. Tried everything and just today left it at the apple store. Not sure they will find anything since it is intermittent. Once every 8 days is exactly what I was seeing. I actually reinstalled software and the problem went away for 3 weeks and then started again.

I hope someone has an answer.

Apr 21, 2010 6:24 PM in response to jsf4

Hi guys,

My fan is due to go crazy tomorrow. I just put the computer in sleep mode starting at midnight. Not sure how this will help but I'll give it a try for the record. Will let you know what happens, if anything. But, you know, we shouldn't have to be doing that just so the fan doesn't go crazy. SOMETHING is wrong.

Hershey's Mom

chevy2410 Author

Level 1

5 points

Apr 21, 2010 6:33 PM in response to Hersheys Mom

I just talked with the Apple tech advisor today and he received the file I sent him and the engineers are looking at it. He says he should have an answer possibly Sunday. As soon as I hear from him as to what is the next step I will post on this thread.

Chevy

21.5' iMac fan speed is to fast