IMac fan keeps running

Since starting my iMAC last night, the fan keeps runnings on high. I have tried restarting several times, ran a diagnostics which found no faults, and checked the CPU usage which is around 10%. Any ideas what else I can try?

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Similar Messages

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    My iMac fan keeps running loudly even when the computer isn't doing any thing, and I just started it up.
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    I also recently had to insert a new hard drive instead of the old one that failed. I am thinking that either the SSD is just hotter than the old hard drive, or that the hard drive sensor is somehow inverted in the plug. Is there any way of testing the hard drive sensor to see if that is faulty, or to test the fan. When I look at the Activity Monitor the system is 87% idle...

    Although you don't mention which imac you have since 2009 Apple has used hard drives with the temp sensor built in. When replacing one of these late model drives you have to use the same type hard drive or you get fans running all the time because the temp sensor isn't detected. You might want to try some third party software such as iStat Menus, SMC Fan Control or HDD a Fan Control. Google them for reviews.

  • Imac fans keep running on high

    I have an old imac 2 ghz intel core duo 21" (white) that we have at our holiday home for email and the kids. It's pretty crappy but does the job. This morning one of the kids accidently unplugged it and when it restarted the fans are going constantly on full. I checked activity monitor and there's nothing happening (CPU, Network or Disk) that warrants the fans. I zapped the PRAM and updated all the system software with no effect.
    Is there anything I can do to reset them to normal? And, if not, should I worry?
    thanks

    Try resetting the SMC
    Desktop Macs
    Shut down the computer.
    Unplug the computer's power cord.
    Wait fifteen seconds.
    Attach the computer's power cord.
    Wait five seconds, then press the power button to turn on the computer.

  • I have an MAC OSX 10.6.7 and when I turn it on the fan keeps running.  I shut down/turn on and it's the same.  Any suggestions?   Thanks.

    I have an MAC OSX 10.6.7 and when I turn it on the fan keeps running.  I shut down/turn on and it's the same.  Any suggestions?   Thanks.

    jean156,
    I am a little confused, you are posting in an iMac forum however your profile only indicates you have a MacPro. While I agree a SMC reset may help please carefully read the link The hatter provided because different Mac's have a different processes for resetting the SMC.
    In the mean time you may want to update your profile (Your Stuff in upper right and click Profile) and also please post in the correct forum to avoid confusion.

  • HT1349 When I start my I Mac desktop the fan keeps running loudly.  Can't get it to turn off.

    When I start my I Mac desktop the fan keeps running loudly.  How do I get it to stop?

    Hello there, Jacquefromaz.
    The following Knowledge Base article reviews the steps to perform a reset of the System Management Controller (SMC):
    Intel-based Macs: Resetting the System Management Controller (SMC)
    http://support.apple.com/kb/ht3964
    Thanks for reaching out to Apple Support Communities.
    Cheers,
    Pedro.

  • Mac mini fan keeps running!

    Today I turn on my mac mini (late 2011) and its fan keeps running... How can I solve it?

    Try resetting the SMC
    Intel-based Macs: Resetting the System Management Controller (SMC)

  • Powerbook fan keeps running

    Hi,
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    Hit the power button while unplugged at least at one time use to be part of SMC Reset procedure - it gets rewritten every year or so it seems.
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  • T410 - 252226G slow start, fan keeps running, BIOS config hangs

    Windows 7 Prof FP1, 80 GB SSD. 4GB Ram
    Some strange unusuall behaviour:
    1. It takes up to 45 seconds before the ThinkPad Screen is shown when starting (latest 1.45 bios version)
    2. When T410 is closed down using W7 system power off;  the fan keeps running until the battery is empty. When de/attaching the charger in this stage the T410 beeps like it's still running
    3. When choosing 'config' option in BIOS the T410 hangs
    Any clue?

    I would do a BIOS reset. If your T410 has no supervisor password, then remove the BIOS battery, leave it out for a couple of minutes and then plug it again.
    When the T410 boots, go to the BIOS, press F9 to load the default values, save and re-start.
    Hope this helps...
    /L40SX/240/240X/2*340CSE/360PE/365XD/380D/380E/380XD/380Z/390/560E/560X/2*570/2*600/600E/750Cs/755C/760CD/760EL/760XD/770E/A20p/A22p
    A31/i1600/G40/R50p/R61i/S30/SL510/2*T22/4*T4x/11*T6x/6*T4x0x/6*T5x0/3*W5x0/W700/3*X2x/4*X3x/3*X4x/5*X6x/3*X6xT/10*X2xx/2*X200T/4*X30x/Z60m/3*Z61x
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  • Fan keeps running.  Maybe from RAM upgrade?

    I recently installed 4G of ram into my computer as the old ram was bad. I didn't notice anything for about 1 1/2 months but all of the sudden my fan keeps running. From what my istat pro says, it ranges from 3000 rpms to over 6000rpms! As you can imagine, this is very annoying. My performance isn't affected but the fan is annoying. I have 4G of 667 MHz DDR2 SDRam. I'm worried about over heating. Could somebody please help me with my fan problem?!

    Thanks, I love being able to answer questions and help people

  • My imac desktop 9.1 the fan keeps running..i have turned off and also pulled power plug but it still runs

    the fan on my imac9.1 keeps running..i shut it down and pulled the plug..did not help

    The fan minimum speeds are about 1200 rpm, so if the Mac is powered on and not sleeping, they're running.
    An iMac's exhaust fans will not run if its power cord is disconnected. If that's what you meant to write, you're hearing something else.

  • My fan keeps running

    the fan in my imac just keeps running

    Hi,  I have the same problem.  I performed these steps in the link:
    Shut down
    Unplugged for 15 seconds
    plugged back in.waited 5
    pressed the power button
    Fan continues to run.
    What should I try next?

  • IMac fan constantly running, I've tried everything!!

    Hi,
    I have a Mac (21.5-inch, Mid 2010)
    Processor: 3.06 GHz Intel Core i3,
    Memory: 4 GB 1333 MHz DDR3,
    Graphics: ATI Radeon HD 4670 256 MB,
    Running Yosemite 10.10.1
    The fan is constantly running quite loud. I have never had this problem until recently and it seems to have started doing it for no apparent reason. I have changed any settings or done anything recently. In fact, the most recent change was upgrading to Yosemite.
    I have tried doing a SMC reset (several times) which didn't change anything. I have tried lots of doing different ways of doing a Apple Hardware/Diagnostics Test and it told me that "The Apple Hardware Test is not compatible with this machine".
    I have kept a close look at my Activity Monitor and nothing is spiking, average use is: System 2.75%, User 5.67%, Idle 90.4%
    Using smcFanControl I know the fan is running at 29C and average 996rpm. I don't know if those stats are normal or not, but my fan is still making more noise than it ever has.
    Please, can somebody help! I have been trying for weeks now with no success. I very worried that using my Mac is going to damage something and I desperately need it for work. Can anybody suggest anything outside of taking it to apple because that is my last resort which is going to cost me a lot of money
    Thank you in advance for your help

    The fans always run, that's normal. What's not normal is that you hear them as much as you do unless you use your imac in an EXTREMELY quiet environment. I think that 996rpm is actually lower than normal, you shouldn't hear that at all. Maybe you have a fan that's starting to fail and is making abnormal noise.
    Running the Apple Hardware Test on your mac requires the original gray install discs that came with the computer when it was new, do you have those? AHT is on disc two, insert it and hold D at start up and AHT will start.

  • Why does my fan keep running

    The Fan on my Imac is constantly running, even after a restart and a shutdown it comes back one one Imac is powered up.

    Last second suggestion that was given to me last week on Friday.  When I unplug power to imac i was unplugging cable from back of imac with cable still plugged into outlet.  The advice that was given is to unplug cable from wall and from back of the imac and then do the SMC reset.  As of Friday internal fan has not come on and i hope i stays like that.

  • My fan keeps running and never stop

    my laptop is dell studio 1458
    the system is the latest archlinx x64, and now i am using kde 4.6
    the problem is that the fan of my laptop keeps running all the time and never stop.
    Is there any solution to this problem?
    Thx...

    The warning is there so that people realize they need to be aware of the possible outcome if they don't properly check their fans during the setting up of the software.
    The guide even suggests to keep a constant watch on the CPU's temperature during testing, and suggests how you can immediately spin up the fans to max in case of a too high temperature:
    Second warning: Some of the steps outlined below describe how to tweak fan speeds. Before doing this be sure you have a low cpu load and are comfortable playing around. If at any time during tweaking you notice the CPU temperature start to rise dramatically, do a echo "255" > /sys/class/hwmon/hwmon0/device/pwm1 to spin up the fan all the way until things cool down. Basically, you should know what you're doing before fooling with the configuration file.
    Alternatively, there's a fan control deamon called dellfand. A related topic can be found here:
    https://bbs.archlinux.org/viewtopic.php?id=54865
    Essentially, all these tools do the same. The temperature is polled and the fan speed is adjusted.
    As far as I know, there is no alternative way / graphical tool to do this for you.
    *edit*
    considering this is a dell studio, have you checked the system's bios to see if the automated fan control is enabled?
    Last edited by stefanwilkens (2011-04-29 13:03:18)

  • First use of Photos: fan keeps running

    In the few weeks that I've been using my iMac Retina I've never heard the fan. This morning I imported a photo from my iPhone 6 and after that I noticed that while the fan was running high, some iCloud xxx app/task was running in Activity Monitor. I've killed it, rebooted my iMac twice, but still the fan starts running high now and then.
    What can I check more?

    Hey Hans Elting,
    This seems to be happening with a number of folks. Here is the link to that discussions.
    high cpu usage all the time
    The solution the had to use was to wait it out and it eventually stopped. How long has this been happening on your mac?

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