Model A1312 / Mid 2011 / 2.7 & 3.1 GHz Core i5 or 3.4 GHz Core i7 Processor

328 Questions View all

Why is the fan so loud?

The fan on my iMac Intel 27" is so loud and I wonder how to fix it

Answered! View the answer I have this problem too

Is this a good question?

Score 1

Comments:

Do you have any other symptoms other than a loud fan? What are the last three numbers of your serial number?

by

is it just loud or is it screeching?

by

Maybe the fan is heavier because of the dust on it

by

My 27" imac had the same problem. The problem was the Ambient Temperature sensor. The ambient sensor plug is on other side of CPU processor. And I think about the temperature of processor, it caused desoldering of logic board one of the capacitor of temperature sensor system. Sorry about my english, It was my problem and was solved, maybe could help others!

by

The problem here is that the OP never came back and told us her exact machine so all the answers are just speculation.

by

Add a comment

17 Answers

Chosen Solution

I wouldn't just drop lubricant on the fan. If the fan is clogged with dust or nicotine it will slow it down even more.

If you can access the fan use some 91% (or 91-99%, do not use anything with a lesser percentage as they can be conductive and if accidently dropped onto a system / logic board can cause electronic components to short out) Isopropral (rubbing / the white NOT green stuff) alcohol and a brush to clean away the dust and debris then add about 2 drops of 3 and one oil down in the center where it gets inside of the fan housing.

If it still makes noise, you probably have a bearing going out - these fans spin hundreds of revolutions per second and will simply wear out ... in this case, replace it, the fans only cost a few bucks.

Was this answer helpful?

Score 7

Comments:

When your in there also use something like a tooth brush, with a dab of alcohol ^ mentioned above to clean off any dust on the exhaust vents.

by

Add a comment

If you changed the hard drive to one without Apples firmware, this can cause run away fan issues.

Was this answer helpful?

Score 4

Comments:

Then how can we solve the problem?

by

With a special cable that has the temperature sensor in it, see my post below.

by

Where is your post "below," Mayer? I don't see anything beyond this point... and I'm dealing with that ambient air sensor issue. Thanks

by

jcarter - Which system do you have a '09 or '11 model? There are different answers here depending on the system. The '11 cable is the link from OWC below in my answer.

by

Show 1 more comment

Add a comment

westly197 - Well, Yes & No here ...

From the '11 model forward Apple uses custom firmware within the HD to allow the internal thermal sensor (note: not all drives have this sensor) to be used as part of its SMC services which in turn controls the RPM's of the fan or fans of the system. If you try using an older non-compliant drive the fans will ramp up as SMC services will think the sensor within the HD is defective. Over time the fans will wear out and the system will be very noisy compared to what it should sound like. Heres a collection of good write-ups from OWC that describes the issue: Apple Further Restricts Upgrade Options on New iMacs and Apple’s iMac 2011 Model Hard Drive ‘Restrictions’ and iMac Hard Drive Upgradeability Expanded!

OWC created a special cable so people could put in noncompliant HD's into the '11 system '11 Upgrade kit at the same time Apple was also working with the JEDEC standards group which over see's the SMART HD standard. While it took quite a bit of time Apple was able to get the group to alter the standard so the thermal sensor with in the HD could be accessed in a common method and not interfere with the performance the the drive (which was why Apple needed to go with custom firmware at the beginning). Now HD's that comply with the updated standard no longer need the OWC cable and have the newer SMART services within their firmware.

If you look at the HD's package you should see an Apple logo on it which is the only clue that I know of. The reason you don't see anything other than that is the drive vendors still have a lot of noncompliant drives out there and they have also being going though a bit of a market collapse and contraction (being more focused on survival). I also suspect Apple may also be asking for a bit of money for the drives they certify as workable.

In the end you need to be smart shopper on what you buy.

Was this answer helpful?

Score 3
Add a comment

There is no a hdd temp sensor in 2011 models , there was till 2010

Was this answer helpful?

Score 1
Add a comment

Check if there are layers of dust on the blades or in the housing of the fans. Buy a can of pressured air and blow off the grit. Be careful to hold fragile components in place so they dont break, e.g. fan blades.

Was this answer helpful?

Score 0
Add a comment

there is no temp sensor cable on 2011 27" iMac hard drive and I've replaced it with the 1 TB WD from my 2010 iMac and I'm sure that its the cpu fan not the hard drive fan that runs at full speed , I've installed windows 8 using bootcamp and when I run fan control software in windows it shows that the GPU temperature goes to 69 to 74 degrees I think that might be the problem

if you hold alt option key and keep viewing the boot screen even for a long time the fan works just normal but when it starts to boot to an OS (windows or OSX) it starts to work at full speed

Was this answer helpful?

Score 0
Add a comment

In the iMacs I have worked on there is a temp sensor cable that runs from the hard drive to the logicboard. You are right that the hard drive itself does not have a fan but if the iMacs use a specific kind of hard drive and there is a thin cable that runs from the hard drive to the logicboard that is called a hard drive temp sensor cable. If that cable is missing it will cause the fan to run at high speeds. I learned about this while working at an apple store. Look it up.

Was this answer helpful?

Score 0
Add a comment

I had the same problem when I swapped out the HD in my imac 27" mid-2011 with an SSD drive. I believe the fan began running full throttle because it did not know how to process the temperature readings of the new drive etc.

I searched online and came across this website - http://www.hddfancontrol.com

(Parenthetically- I am not that tech savvy but I do not recall seeing or detaching a temp sensor or wire)

I installed their program and have not had any problems since (it's been at least 6 months).

Good Luck!

Mike

Was this answer helpful?

Score 0
Add a comment

That is true. The software from the website above is fantastic. About $35. The iMac went completely quiet. You can set the temperature and speed of the fan as well. I strongly recommend it. Tin

Was this answer helpful?

Score 0
Add a comment

After installing 2TB toshiba drive i got same problem. I solved it with 'Macs Fan Control'. No need to waste 35$. Get fun

official link: http://www.crystalidea.com/macs-fan-cont...

Was this answer helpful?

Score 0

Comments:

All I can say here is: Caveat Emptor   Any software solution that defeats the thermal controls the system has can effect your lifespan of your system or cause other odd effects. The best approach on these systems is to use drives who's firmware works with the internal sensor correctly or use a external sensor that intercepts the signal (which is the solution I prefer).

by

Add a comment

Actually my hdd fan rpm based on toshiba thermal sensor now. After 3 month i got no problems with it. So i dont know what are u talking about.

Was this answer helpful?

Score 0

Comments:

Some software solutions just ramps up the fans and does not access the HD sensor. Also the given HD you put in may not 1) have a thermo sensor 2) it may not be accessed by the system because the wrong cable was used {power} 3) If the SMART thermo interface was used then you will be slowing down your HD as the SMART services (current rev) causes the HD's I/O to be interrupted for the sensor to be read (which is how FanControl works). A new standard should be ratified this fall which does away with the interrupt (which is why Apple does not use it). But only newer HD's that meet the new spec will have this. You can get an external sensor board that you splice into the power sensor line that then handles the temperature monitoring like the older HD's did before. This is the best way currently.

by

Add a comment

If you installed another non-apple main hard drive and removed the 3.5 original drive, then it is the temperature sensor/firmware issue you are having. A safer method to the software solution that forces the fans to run slow....even if things get too hot... Is a special sensor cable that plugs between the new hard disk and the cable in the iMac, and have a thermal sensor you attach to the drive much like older models had. They can be had for $50-$80 from what I've seen, do a little searching. This way the system can still regulate fan speed as temperature dictates, it will pass hardware diagnostics, etc.

Was this answer helpful?

Score 0

Comments:

westly197 - How about focusing on newer topics. Many of todays HD's (made after Feb '14 give or take) don't need fan software or special hardware as they are now fully compatible with Apple SMART interface.

by

Add a comment

Hey Dan, I have the 2011 iMac and just faced this issue so thats why its on my mind. Also the newest models are less likely to have fan issues. I am interested in knowing what drives might work without the need for the cable. I've not heard this before and was under the impression only an Apple drive with special firmware for the mid2011 models was required. Ive not read anything indicating any off the shelf standard drive would work.

Was this answer helpful?

Score 0
Add a comment

There is a cable coming from the motherboard to the back of the screen that splits in two to the left of the ribbon cable, I guess the ambiance thermal monitor is there, it is cover with some tape, if the top plug unplugs the fan goes full speed it is very easy to do by tilting the screen ,and not notice it, remove the tape very careful end re-plug the top plug and problem is solved.

Was this answer helpful?

Score 0
Add a comment

Thank you Dan. I was going to purchase Apple brand harddrive used in 2013 Imacs. And then, I was going to install this hard drive in my 2011 Imac as a remedy. The harddrive you suggest, does it have to be a SSHD? Can I use regular SATA3 harddrive, as well?

Was this answer helpful?

Score 0

Comments:

I know this Seagate's SSHD's work in the '11 model. I haven't tried the Seagate's regular HD's. I think you'll be happier with the SSHD as it will give you a big performance improvement over a standard HD. Hybrid drives have become the best replacement on the older single drive systems. While you could put a second drive in this system (SSD). The amount of work needed to put in the extra SATA & power cables for the 2nd drive and the hassle of setting up the Fusion drive makes the SSHD option just easier and just as good.

by

The Apple logo'ed drives (real OEM Apple drives) are equal or more expensive for the same size SSHD.

by

Add a comment

I've seen this problem before and it was because the hard drive was replaced with a different brand but the hard drive sensor cable was not changed. Different brands use different temp sensor cables. That might be the problem.

Was this answer helpful?

Score -1

Comments:

This model iMac doesn't have the sensor cable, there is no real work around aside from running software to control the fans' speed.

by

Add a comment

give it a good oiling with some grease ..don't use WD40 it good but lasts only a few days ..give it a good clean as well.

Was this answer helpful?

Score -2
Add a comment

Add your answer

Jessica Holst will be eternally grateful.
View Statistics:

Past 24 Hours: 11

Past 7 Days: 105

Past 30 Days: 332

All Time: 24,644