iMac Mid 2011 i5, fans on full constantly

[LAHegarty]

-iMac 2011, fans on full constantly-

Macs Fan Control stopped the problem but only if that is installed, running and I'm logged in.

Any idea what might be causing this?

I've tried as follows:
- PRAM reset
- SMC reset
- Tried different RAM
- Clean install

Would like to try a firmware update but can find any that will work on this iMac...

Maybe you know how to fix this.

 

[Richdmoore]

Do you have the original hard drive in the system? If not, you either need a software solution, or to install the hardware kit owc sells to stop the fan issues.

(The original hard drive had specific firmware to communicate temperature to the iMac, if the hard drive is replaced without that Apple specific model hard drive firmware, the temperature data is not sent. This causes the computer fans to go into a failsafe mode of full speed.)

 

[LAHegarty]

Richdmoore Thanks.

Yes, I have 2x SSD's installed, I guess I'll be using Macs Fan Control.

 

[nambuccaheadsau]

Even better would have been OWC Heat Sensor Kit when the original drive was removed.


https://eshop.macsales.com/item/OWC/DIDIMACHDD11/

 

[LAHegarty]

Shockingly, available on eBay UK: https://www.ebay.co.uk/sch/i.html?_from=R40&_sacat=0&_nkw=Owc+Kit+For+Imac+2011&_sop=15

£15 a pop!

I'm wondering if I would need one for each drive, I think I'll stick with software fit due to the cost :/

Thanks, Guys.

 

[Darmok N Jalad]

Shockingly, available on eBay UK: https://www.ebay.co.uk/sch/i.html?_from=R40&_sacat=0&_nkw=Owc+Kit+For+Imac+2011&_sop=15

£15 a pop!

I'm wondering if I would need one for each drive, I think I'll stick with software fit due to the cost :/

Thanks, Guys.

Nothing wrong with MFC as a solution. I have it installed on my 2017 iMac just for monitoring purposes. It's a great tool to check temps across the system.

 

[LAHegarty]

Darmok N Jalad I love it too! It's on all my Macs.

 

[Guy Clark]

I had the same issue with my Mid 2011 21.5" iMac after replacing the stock HDD with a Solid State Hybrid Drive. The solution for me was to install Macs Fan Control and set everything manually to 1200rpm
https://www.crystalidea.com/macs-fan-control