MacBook Loud Fan Problem

[TET879]

My MacBook fan has recently started regularly spinning at speeds of about 6000rpm even though none of it is running hot.

I googled and found several suggestions about checking print queues and looking in the activity monitor but none seemed to help.

I am not running high demand applications (just browser, itunes, stuff like that) and none of my MacBook is hot. The fan is just spinning very fast.

Any suggestions?

 

[Brian Y]

My MacBook fan has recently started regularly spinning at speeds of about 6000rpm even though none of it is running hot.

I googled and found several suggestions about checking print queues and looking in the activity monitor but none seemed to help.

I am not running high demand applications (just browser, itunes, stuff like that) and none of my MacBook is hot. The fan is just spinning very fast.

Any suggestions?

If there's nothing in activity monitor using the CPU, might be worthwhile taking it to Apple for diagnostic.

 

[mrsir2009]

Have you tried resetting the SMC?

If your Mac's fans are unjustifiably loud, chances are the System Management Controller (SMC for short) is malfunctioning. The SMC controls many of the most basic, low level functions on your Mac, which includes operating the fans. It is not uncommon however for the SMC to mess up and set the fans to a high speed when not needed - An issue which can easily be resolved by resetting the SMC:

Steps to rest the SMC on a Macintosh Laptop:

1. Shut down the computer.
2. Plug your Mac in, if not already plugged in.
3. Press (left side) Shift-Control-Option & 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.

[source]

 

[TET879]

Have you tried resetting the SMC?

Yes, I tried this the other day and it has not made any difference. Any other suggestions?

 

[mrsir2009]

Yes, I tried this the other day and it has not made any difference. Any other suggestions?

Exactly what sort of temps is your macbook running at?

 

[TET879]

Generally the maximum it would get to is about 70c when under heavy load. Though now the temp is often not above 50c when the fan kicks in to high gear. Though it has run hotter and the fan hasn't kicked in, so it doesn't appear to actually be influenced by the temperature.

I did a quick hardware check and got the error code 4SNS/1/40000001: TN1D--1.000. After googling it appears this points to a faulty heat sensor. Is taking it in for repairs my only option? Student here so I don't have money to burn so any other solution would be hugely appreciated.

 

[brop52]

Which machine are you using? Unibody or non-unibody? Can you post a screenshot of iStat Pro with all the fan RPMs and temps?

If you bring it to Apple they will not charge to look at it. They will tell you how much the repair will be. (They may recommend complete logic board replacement in which case that's up to you whether you want to do that).