Fans disabled

[adnbek]

So I installed Yosemite Beta on a test system (my macbook air 2013) and now fans remain on idle permanently to the point the laptop gets uncomfortably hot. I tried an SMC reset which didn't fix it.

Anybody else have this issue?

 

[Apple_Robert]

Check your activity monitor and see what processes are continuing to run. You might find the culprit and subsequently stop the process allowing your fans to do the job.

 

[adnbek]

There is no running process can could possibly interfere with the fans this way. Besides that, they stopped working regardless of whether I boot into Yosemite or back to my original Mavericks partition.

Whether it's an SMC issue or else, it happened during the Yosemite install. There was a moment during the install when it updated the SMC to a new version and since then the fans have become rendered permanently disabled.

 

[Apple_Robert]

There is no running process can could possibly interfere with the fans this way. Besides that, they stopped working regardless of whether I boot into Yosemite or back to my original Mavericks partition.

Whether it's an SMC issue or else, it happened during the Yosemite install. There was a moment during the install when it updated the SMC to a new version and since then the fans have become rendered permanently disabled.

Have you tried restoring to Mavericks?

 

[DeltaMac]

Try a dedicated utility to control the fan, such as Macs Fan Control
http://www.macupdate.com/app/mac/47386/macs-fan-control

 

[adnbek]

Have you tried restoring to Mavericks?

I didn't want to do that yet since I'd like to test out Yosemite. And even if I did, if it's an SMC firmware problem I can't downgrade to a lower version anyway.

 

[adnbek]

So just to update. I can confirm that something in the installation went awry and now CPU temp sensor has been disabled (shows 0c permanently) and therefore the fan is stuck on idle.

Tried a utility to raise fan speed and fan doesn't respond even when I increase the RPM, stuck at 1195.

 

[DeltaMac]

Boot to your Diagnostics test.

http://support.apple.com/kb/HT5781
Does that pass?

Boot into Safe Boot mode (Restart while holding the Shift key)
Can you run the fan utility (and control the fan) while booted in Safe Boot mode?

 

[adnbek]

I have a theory as to what may have happened. Since I was at 100% battery when I installed Yosemite, I didn't feel the need to plug it in to power. I believe the SMC update (2013 Air models get an SMC update with the installation) may have corrupted due to the fact it wasn't plugged in.

(it is required for SMC firmware updates but I had no idea the SMC was gonna be updated and no warning was giving as such)

I recall the computer KPing during installation, can't remember when but could've been during the SMC update. I tried a reinstallation but sadly since the SMC versions match, it won't reinstall the SMC firmware a second time.

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Boot to your Diagnostics test.

http://support.apple.com/kb/HT5781
Does that pass?

Boot into Safe Boot mode (Restart while holding the Shift key)
Can you run the fan utility (and control the fan) while booted in Safe Boot mode?

Diagnostics show no problems found. Safe mode same result. Temp at 0c, fan stuck on idle.

 

[DeltaMac]

I think you may have shot yourself in the foot! (screwed the pooch, etc, etc)
(Now you know it is a really bad idea to try a major install on batteries only )
I suspect that you have a corrupted SMC update, which may not be repairable, without replacing the logic board.

I have not seen a firmware update that would start without warning you that the power adapter needed to be attached.

Be sure to try the SMC reset again - double-check you are following the exact steps, as outlined in this article: http://support.apple.com/kb/HT3964

and - I'm out of ideas.
Take it in for service. (An Apple-authorized service shop or Apple store has other factory tests that MAY have other, potentially good, results, such as "kick-starting" (individually testing) the fan.

 

[adnbek]

I think you may have shot yourself in the foot! (screwed the pooch, etc, etc)
(Now you know it is a really bad idea to try a major install on batteries only )
I suspect that you have a corrupted SMC update, which may not be repairable, without replacing the logic board.

I have not seen a firmware update that would start without warning you that the power adapter needed to be attached.

Be sure to try the SMC reset again - double-check you are following the exact steps, as outlined in this article: http://support.apple.com/kb/HT3964

and - I'm out of ideas.
Take it in for service. (An Apple-authorized service shop or Apple store has other factory tests that MAY have other, potentially good, results, such as "kick-starting" (individually testing) the fan.

Hah, yeah it seems I have no choice but to take it for repair. And had I know a SMC firmware update was going to be included with the Yosemite install, I definitely would've kept it plugged in. No warning was given about that.

 

[qaddodi]

I had this problem a while back (much before Yosemite) and I fixed it by resetting the SMC. http://support.apple.com/kb/HT3964?viewlocale=en_US&locale=en_US Use this guide to help you how you do it.
I also put up my laptop after resetting the SMC holding it in front of my AC, and I guess either the air coming from the AC or resetting the SMC helped re-run the fans. It started working by making a weird noise at first but then went back to normal. It's been working ever since. Try this before taking it to repair and paying for it.

Let us know how it goes.

 

[adnbek]

I had this problem a while back (much before Yosemite) and I fixed it by resetting the SMC. http://support.apple.com/kb/HT3964?viewlocale=en_US&locale=en_US Use this guide to help you how you do it.
I also put up my laptop after resetting the SMC holding it in front of my AC, and I guess either the air coming from the AC or resetting the SMC helped re-run the fans. It started working by making a weird noise at first but then went back to normal. It's been working ever since. Try this before taking it to repair and paying for it.

Let us know how it goes.

Tried resetting SMC, nada. Appointment booked... should be covered by the warranty considering it's a public beta, right?

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Should be a warning stickied in this forum or the official beta thread warning that due to a possible SMC update included with Yosemite, one should have it plugged to power despite the installer letting you proceed otherwise.

 

[xjrlokix]

Tried resetting SMC, nada. Appointment booked... should be covered by the warranty considering it's a public beta, right?

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Should be a warning stickied in this forum or the official beta thread warning that due to a possible SMC update included with Yosemite, one should have it plugged to power despite the installer letting you proceed otherwise.

I have the same "problem" and I created a report. Personally, I would wait for the next update or even the final version. It is a beta and stuff like this is related to it so give them the chance to fix it.

 

[adnbek]

I have the same "problem" and I created a report. Personally, I would wait for the next update or even the final version. It is a beta and stuff like this is related to it so give them the chance to fix it.

Yeah... was wondering about that too. Can a corrupt SMC be fixed by a software update? I remember reading somewhere that should a SMC firmware update fail nothing can be done except replace the logic board.

 

[xjrlokix]

I installed smcFanControl to check my fans. Per default, they run with something like 2k (MacBookPro 15" Retina early 2013). I opened a game of Civ5 where normally the menu alone starts the fans. But it stayed the same. I reopened smcFanControl to check the temperatur: 90°C.

I manually set the fan speed to full power and they started to kick in. Temperature is now down to 77°C and falling, Civ5 is still in the lobby, in the background.

So I guess it is a software bug.

 

[lexR]

Just before logging off tonight I noticed my core temps running high (Mac Pro 4.1-5.1 OSX10.10 beta, 12 core X5670's) and my fans were at idle, don't normally see my temps go over 60c and the fans be at idle, manually ramped them up with istat which brought the temp down straight away so that mirrors what you guys are saying??

 

[xjrlokix]

Just before logging off tonight I noticed my core temps running high (Mac Pro 4.1-5.1 OSX10.10 beta, 12 core X5670's) and my fans were at idle, don't normally see my temps go over 60c and the fans be at idle, manually ramped them up with istat which brought the temp down straight away so that mirrors what you guys are saying??

Don't know what the idle temp of a MacPro should be. I know when my MacBookPro is getting forced to do some more heavy stuff (games, lightroom) the fans start to spin right away. They stopped doing this with 10.10 and now I control them manually when I do any of these tasks.

 

[adnbek]

My case is much worse than you guys. The fans won't respond to any utility that control fan speeds. They're stuck at idle. CPU temp sensor also dead.