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dilap

macrumors 6502a
Original poster
Apr 18, 2014
813
60
London, UK
I have a MacBook Air 13" Late 2010 2.13GHz, and my fans are extremely loud, sometimes on little CPU usage. SMC resets hardly work and I can't contact Apple without paying the £35.00 for one off support, let alone how much it is for repairs. But lately it's been getting worse, today I started my Mac up and the moment it got to the login screen, the fans went CRAZY. My CPU usage was high at first but after logining in and closing things using Activity Monitor it went down. However the fans still kept going crazy. I had to put my Mac to sleep, and even then the fans kept going for a while. It happens in OS X Mavericks 10.9.4 and OS X Yosemite Developer Preview 5. I don't think a restore will help because it happens on both OS's. I have tried App Tamer as well. My MacBook Air is well ventilated, and I was thinking all Fans are like that on MBA's? Or it's a Late 2010 issue?
 
Last edited:

Hexcruncher

macrumors regular
Aug 5, 2014
107
36
SMC Reset

You may need to try an SMC or PRAM/NVRAM reset.

The SMC is the Macs System Management Controller, and it controls a lot of the core hardware functions such as displaying the correct LED on the MagSafe adapter, The computing waking from sleep when you lift the lid of the mac, and other core functions which includes the fans on the machine. Resetting the SMC could solve this problem

Instructions from Apple's Support page:

Resetting the SMC on portables with a battery you should not remove on your own
Note: Portable computers that have a battery you should not remove on your own include MacBook Pro (Early 2009) and later, all models of MacBook Air, and MacBook (Late 2009).


  1. Shut down the computer.
  2. Plug in the MagSafe power adapter to a power source, connecting to the Mac if it is not already connected.
  3. On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time.
  4. Release all the keys and the power button at the same time.
  5. Press the power button to turn on the computer.

Note: The LED on the MagSafe power adapter may change states or temporarily turn off when you reset the SMC.




If you get stuck there are some great videos of this on YouTube. Best of luck!
 

AppleFanatic10

macrumors 68030
Nov 2, 2010
2,802
295
Hawthorne, CA
It could be a logic board problem. I had this exact same problem when I first got my MB.. The fans would go crazy when I was doing nothing but they would turn off when I put my MacBook to sleep.
 

dilap

macrumors 6502a
Original poster
Apr 18, 2014
813
60
London, UK
You may need to try an SMC or PRAM/NVRAM reset.

The SMC is the Macs System Management Controller, and it controls a lot of the core hardware functions such as displaying the correct LED on the MagSafe adapter, The computing waking from sleep when you lift the lid of the mac, and other core functions which includes the fans on the machine. Resetting the SMC could solve this problem

Instructions from Apple's Support page:

Resetting the SMC on portables with a battery you should not remove on your own
Note: Portable computers that have a battery you should not remove on your own include MacBook Pro (Early 2009) and later, all models of MacBook Air, and MacBook (Late 2009).


  1. Shut down the computer.
  2. Plug in the MagSafe power adapter to a power source, connecting to the Mac if it is not already connected.
  3. On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time.
  4. Release all the keys and the power button at the same time.
  5. Press the power button to turn on the computer.

Note: The LED on the MagSafe power adapter may change states or temporarily turn off when you reset the SMC.




If you get stuck there are some great videos of this on YouTube. Best of luck!

As I said I tried the SMC Reset, but how do u reset the PRAM?

----------

It could be a logic board problem. I had this exact same problem when I first got my MB.. The fans would go crazy when I was doing nothing but they would turn off when I put my MacBook to sleep.

Thanks, will I have to replace the logic board? How did u fix it?
 

iPhysicist

macrumors 65816
Nov 9, 2009
1,343
1,004
Dresden
The Question is: Does it get hot and the fan is just responding to the usage? Or does the fan go crazy without reason? If its the latter. Set it up as new. If that is not the case, do you feel the airflow form the fan? No? Then maybe you have to much dust collected inside the fan. You should just detach the bottom of your MBA and use a vacuum to clean the fan. This often is enough but if its none of the above you maybe have a defective motherboard as already mentioned.
 

dilap

macrumors 6502a
Original poster
Apr 18, 2014
813
60
London, UK
The Question is: Does it get hot and the fan is just responding to the usage? Or does the fan go crazy without reason? If its the latter. Set it up as new. If that is not the case, do you feel the airflow form the fan? No? Then maybe you have to much dust collected inside the fan. You should just detach the bottom of your MBA and use a vacuum to clean the fan. This often is enough but if its none of the above you maybe have a defective motherboard as already mentioned.

I just cleaned the fan. The case didn't come off fully as I had a stripped screw(the MBA's preowned) and I managed to get a vacuum in. I'll update if it worked or not.
 

dilap

macrumors 6502a
Original poster
Apr 18, 2014
813
60
London, UK
How did you vacuum it if you didn't get the case off?

It was only one screw so when I tried to take it off it lifted off about 2-4 inches, luckily the fan was on the opposite side of the striped screw so I was able to access it easily.

----------

It appears to be fixed, thank you all! iPhysicist, your soloution was perfect. Thanks iAppleFanboy, if the issue comes back, I will look for your solution, its still under warranty with the eBay seller so they will do it.



:apple::):apple::):apple::):apple::):apple::):apple::):apple::):apple::):apple::):apple::)
 

dilap

macrumors 6502a
Original poster
Apr 18, 2014
813
60
London, UK
Dust or dirt on fan does not usually make the fan go to high RPM when it first starts up and only does this after heating or over heating.

No matter, glad it works.

Thanks. It was probably just Yosemite and some app doing something, maybe it was overheating, it was quite hot to touch the black bar above the keyboard. I left it for ages, it had really infuriated me and I didn't want to use it! Airmail still makes my fans go bad but it uses a lot of cpu.
 

iolinux333

macrumors 68000
Feb 9, 2014
1,798
73
Note the mid-2011 MBAs did this because of a bug introduced in Mavericks and the issue was only resolved two weeks ago with a software update. I don't know, and doubt this is/was your issue, but it's something to keep in mind.
 

russellj

macrumors newbie
Feb 19, 2015
1
0
Just to add my 2 cents: My 13" Macbook Air Late 2010 had a very similar problem:

Kernal CPU usage over 100%
Constant freezing, beach ball, etc.
Fan at constantly high speed from startup
Updates, PRAM reset, SMC reset, etc, non-helpful
Dispair.

The problem ended up being a problem with the connector that goes over the fan (easily viewable if the bottom is removed). It had evidently jostled loose by way of a drop or two.

Also had some wine spilled on it a few months before.

Cleaned (isopropyl alcohol, Q-tip) and reinstalled that connector and the issue disappeared.

https://d3nevzfk7ii3be.cloudfront.net/igi/kpxaSggiRGXdYbjE.huge
 

dilap

macrumors 6502a
Original poster
Apr 18, 2014
813
60
London, UK
Just to add my 2 cents: My 13" Macbook Air Late 2010 had a very similar problem:

Kernal CPU usage over 100%
Constant freezing, beach ball, etc.
Fan at constantly high speed from startup
Updates, PRAM reset, SMC reset, etc, non-helpful
Dispair.

The problem ended up being a problem with the connector that goes over the fan (easily viewable if the bottom is removed). It had evidently jostled loose by way of a drop or two.

Also had some wine spilled on it a few months before.

Cleaned (isopropyl alcohol, Q-tip) and reinstalled that connector and the issue disappeared.

https://d3nevzfk7ii3be.cloudfront.net/igi/kpxaSggiRGXdYbjE.huge

Thanks! I will look into this. The fan and vacuum actually didn't help, but I used MacFanControl and it runs at a constant 2300 rpm, unless it is getting slow and laggy, in which case I let it cool of.
 
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