iMac 27-inch, Mid 2011 making loud fan noise for no reason. Help?

Reset the SMC and PRAM each 3x back to back, sometimes it doesn't take the first time. If you don't know how follow these directions to the letter:

Intel iMac SMC and PRAM resets

If still no luck then post back.

Good deal!

Hey same problem here. I have a mid 2011 iMac 27" which was a beauty until a few months ago when the fan became loud. I didn't notice it at first because I was using Ableton Live9 plus a few other programs with my headphones on. But now it really is disturbing. I've done the SMC and PRAM resets thrice like you mentioned above... But still no luck. It goes loud on idle.

I am not happy with the service I get from Apple Japan. I started to buy second hand Macs so as to use them because Japanese they buy them and get disappointed because they can not install windows they sell them hardly ever used.

I got an iMac pretty cheap and still within the year for getting ACPP for another 2 years during that time it had a lot of problems everytime the DVDs would scratch inside and I had 3 replacements of Install sets apart from falling in the eathquace Apple would not replace it and still scratching DVDs they made me tired having to send it in ,Maybe they thought I would buy a new one I had 2 Superdrives 1 HD 1 Panel 1 Stand and I was still refused a new one because I bought it Second Hand witha couple of months left from 1 year Warrenty but I tried to use it.

So after the 2013 June ACPP expire I had set it up to Install Mavericks as well as having 10.6 the Bundled and 7 8

and put 8 GB of memory so I spent money I got iworks iLife f

I got an iMac pretty cheap and still within the year for getting ACPP for another 2 years during that time it had a lot of problems everytime the DVDs would scratch inside and I had 3 replacements of Install sets apart from falling in the eathquace Apple would not replace it and still scratching DVDs they made me tired having to send it in ,Maybe they thought I would buy a new one I had 2 Superdrives 1 HD 1 Panel 1 Stand and I was still refused a new one because I bought it Second Hand witha couple of months left from 1 year Warrenty but I tried to use it.

So after the 2013 June ACPP expire I had set it up to Install Mavericks as well as having 10.6 the Bundled and 7 8

and put 8 GB of memory so I spent money I got iworks iLife family packs and Movies all Scratched.

So I talked to Sendai Apple store and they would have a look and made a date to come in and

show them what the iMac does to the DVDs ,it takes about 10 minutes to load and makes a lot of noise and then when it is done they are scratched , we can come to some agreement I want a refurbished replacement for all the money I have spent and lost and damaged DVDs

Our Appointment was cancelled because ,the Delivery Company had not appeared after three days I can walk to the shop in 30 minutes but they wanted to pay for collection.

Meanwhile I was without a Desk top , Apple Store offered me 10% discount if I got a new one,

I refused because I want to use old apps.

So I was looking around at the second hand places and saw 2012 iMac very cheap Junk ! I ask the guy why such a new one was junk ,he was mean and said if you want to buy it ,buy it no info and no inspection then he said we are not selling its for parts !

I thought that it might be just some minor problem and this shop not spending time finding the cause,so I bought it

And tested it on the Network AHT an found Error 4 SNS / 1 / C 0 0 0 0 0 0 8 : T L 0 p - - 1 2 4 when it got to the logic board pass it stopped.

I took it to Apple this morning 40 minutes carried it well packed and had a consultation ,Ms Genius tested it and found

Temperature Sensor L C D TETHERED CAN NOT READ T C ON LOCAL ,That is why the Fan is going full Biff.

She said you best not use it and have it fix a new LB no ! no ! no ! way ! When I chatted with Apple hew asked me did you try to install windows .

I guess he saw some Data that the original owner did ! so I bet it was that but he failed and I lost again Apple seems to win because we do not know how these PC work but they break easily.

Now I do not want to pay for a new MB LB whatever Apple should fix it for free because I try to keep the machines usable by buying and fixing them if I can but Apple should help me half way.

Instead of throwing them.