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Imac Error Message 4SNS/1/40000000:TH00-9.000

I have an Inter Imac 3.06 I3 and just upgraded the harddrive from a 500gb to a 3tb Western Didgital Cavalier green.


As far as I can see, everything was put back correclty (not much to move when installing anyway) but ever since I put it all back, used time machine to get it back to the way I wanted (of sorts) after about 10-30 mins the Mac fan kicks in. Never did that before. Now this never happened before and the drive runs quiet and you cannot feel it over heating.


I ran the Apple Hardware test and it came up with 4SNS/1/40000000:THOO-9.000


As far as I can see, this and every other code seems to relate to the imac fan switching on when ever it wants.


any ideas on how I can rectify this issue without have to revert back to the old hard drive?


Thanks


G

iMac, Mac OS X (10.7.1), Mid 2010 - aluminum Model - Intel

Posted on Oct 22, 2011 12:59 AM

Reply
8 replies

Oct 22, 2011 7:24 AM in response to gary172

From 2009 onward iMacs come with HD's that have circuitry for fan sensors integrated into the drives. This means if you installed an off the shelf HD it probably is missing this circuitry therefore causing the fan malfunction. In order to fix the problem correctly you will need to remove and replace the drive currently installed. I would recommend contacting either OWC (www.macales.com) or a local AASP for information about what drives will work in your machine.

Oct 7, 2017 6:56 AM in response to gary172

This is a clear and 100% effective solution for all iMacs with 4SNS/1/40000000:TH00-9.000 problem after replacing a HDD: iMac 21,5" & 27" - błąd 4SNS/1/40000000: TH00-9.000 po wymianie HDD • Forum ELVIKOM

Please note that Macs Fan Control DOESN'T solve the problem because you still have an error in Apple Hardware Test! Macs Fan Control does only control fan speeds and has nothing to do with a HDD temperature sensor detection.

My solution resolves all the issues after HDD replacing, like:

- Mac OS runs very slow,

- fans are running at the maximum speed,

- kernel task is equal or above 100% in Activity Monitor,

- AHT and ASD are reporting TH00 temperature sensor error.

Imac Error Message 4SNS/1/40000000:TH00-9.000

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