MacBook Pro fan running constantly?

stevemclintock · 5 Jul 2007 at 09:23

Hey folks

I recently had to take my MacBook Pro in for repair to get the right fan replaced as it was making a loud grinding sound inside the case. I got it back today and it has been working fine up until I shut it down and then turned it on again about an hour ago.

What's happening is the right fan is now constantly on, spinning at a constant 6000+ RPM, and its getting really annoying! The fan comes on as soon as the power button is pushed, and it simply won't go off. My MBP running at 41C and is cool to the touch, so I don't see why the fan needs to be on.

I've tried installing smcFanControl to manually turn the RPM's down, but I can only get the left fan to be controlled this way, the right fan won't budge from 6000+ RPM, its currently running at 6425RPM as I type this and its been the same for an hour now.

Do I take it back to the repair shop (a premium Apple reseller) and spend another fortnight without my laptop .... or is there some way I can fix it myself? Do you think wiping the hard drive and restoring with my OS X discs I got with the MacBook Pro might work?

I'm doubtful that wiping the hard drive will reconfigure the fans though, as the right fan turns on full blast as soon as the power button is pushed before it even gets to the Apple logo startup screen. I'm thinking that its probably a hardware issue now and the fan is now jammed at full RPM.

Please let me know what you think, and thanks any help,

Steve.

chex · 5 Jul 2007 at 09:40

sounds like they forgot to plug something in

J1234 · 5 Jul 2007 at 09:52

I would take it back again, it's most probably a hardware related problem not software so reinstalling wont sort it.

Other than that you could reset the PRAM it sometimes fixes problems.

stevemclintock · 5 Jul 2007 at 10:46

Hmm, resetting the PRAM & NVRAM might be worthwhile, i'll give it a go when I get back tonight.

I've left it on for the day whilst i'm in work to see if the fans do eventually go off.

I'm not sure if its the repairers fault though, they started it up in the store when I went to collect it and it was fine, no fans on at all. When I got home it was working fine for 3 to 4 hours, then I shut it down and restarted it again about an hour later and the right fan started up on full RPM as soon as the power button was pressed.

thanks for the replies

JPL · 5 Jul 2007 at 14:04

chex said:
sounds like they forgot to plug something in

Sensor wire left upplugged-the noobs(and stressed out apple repair depts) fave!!!

The fans will run 100% if a sensor has failed, try running the Hardware tests from Install DVD1 (hold down d while booting) and see it reports a SNS error.

Have a look in Activity Monitor to see if you have a process running that uses up a lot of CPU, making your computer temperature go up and the fan spin harder in turn.

stevemclintock · 5 Jul 2007 at 14:32

JPL said:
Sensor wire left upplugged-the noobs(and stressed out apple repair depts) fave!!!

The fans will run 100% if a sensor has failed, try running the Hardware tests from Install DVD1 (hold down d while booting) and see it reports a SNS error.

Have a look in Activity Monitor to see if you have a process running that uses up a lot of CPU, making your computer temperature go up and the fan spin harder in turn.

bah, yeah that would make sense. how annoying! so why do you think the fan would appear to have worked for a while and then suddenly start to run at full RPM after a couple of restarts?

thanks for the reply though, now i have something to go by when i take it back into the repair shop

i'll drive a hardware test tonight then and see if it brings up any errors.

slinxy · 5 Jul 2007 at 15:23

they forgot to recalibrate the fans mate.

Theres a program on the engineers cd to run to recalibrate the fans, if they removed the heatsink and fan for whatever reason. five minute job for the shop as only ASP will be abble to download the software.

stevemclintock · 5 Jul 2007 at 15:38

slinxy said:
they forgot to recalibrate the fans mate.

Theres a program on the engineers cd to run to recalibrate the fans, if they removed the heatsink and fan for whatever reason. five minute job for the shop as only ASP will be abble to download the software.

hmm, is there any way i can download this software and run it myself?

if i take it into the shop again they'll probably take it away for at least another week, if its just a 5 minute job to run a software app from a disc then surely i can do this myself.

slinxy · 5 Jul 2007 at 16:02

stevemclintock said:
hmm, is there any way i can download this software and run it myself?

if i take it into the shop again they'll probably take it away for at least another week, if its just a 5 minute job to run a software app from a disc then surely i can do this myself.

Sorry mate, its not possible as you can only download it from GSX site and you need to be an apple repairer with a user account. I can't really post it on any sites for you to download or email you it as its an iso with a load of other stuff on the disc. and I can get slapped from apple for it.

You can try a firmware update on the mac, basically thats where the recalibrate software writes the information to; if your mac's firmware is not upto date, I heard thats worked for some of the lads here when they can't be bothered to download the recalibrate software.

stevemclintock · 5 Jul 2007 at 16:28

slinxy said:
Sorry mate, its not possible as you can only download it from GSX site and you need to be an apple repairer with a user account. I can't really post it on any sites for you to download or email you it as its an iso with a load of other stuff on the disc. and I can get slapped from apple for it.

You can try a firmware update on the mac, basically thats where the recalibrate software writes the information to; if your mac's firmware is not upto date, I heard thats worked for some of the lads here when they can't be bothered to download the recalibrate software.

oh well.

my firmware is up to date so i doubt that option will work, but i've heard the recalibrate function is on some apple hardware test's so i'll run mine tonight and see ... i won't get too hopeful though

fortunately i know a few of the staff at our local apple reseller so i might take it in at the weekend and if their not too busy ask if they have access to do it on the spot, i doubt that'll happen though as they send the laptops off to their head office for repairs.

slinxy · 5 Jul 2007 at 17:29

they should'nt need to send it away - ask them to download it for the the apple GSX (global service exchange) someone at the shop must have assess to it; as thats what all apple repairers should be using to report repaires, request parts etc...

stevemclintock · 5 Jul 2007 at 21:21

I ended up re-installing OS X using my restore discs, but the right fan is still at full RPM ... I figured there would hopefully be a firmware available for me to download (for recalibrating the fans) but there isn't!

I've got a ton of updates to install though including Mac OS X 10.4.10 (i'm on 10.4.8 at the moment) and the file size of the update is 304MB. Do you think this will do the trick and recalibrate things once its installed?

stevemclintock · 5 Jul 2007 at 22:46

Just installed all the updates to no avail

Guess i'll be taking it in at the weekend again then!

slinxy · 6 Jul 2007 at 07:11

The firmware updates are not affected by the os files, so not matter how many times you format and reinstall it will have the same firmware.

stevemclintock · 6 Jul 2007 at 08:30

slinxy said:
The firmware updates are not affected by the os files, so not matter how many times you format and reinstall it will have the same firmware.

ah, i see.