Fan Issue After Updating to macOS Sierra

Follow the steps in these articles : Reset the System Management Controller (SMC) on your Mac - Apple Support

: About the fans in your Mac - Apple Support

: Mac notebooks: Operating temperature - Apple Support

: See how apps affect Mac performance, battery runtime, temperature, and fan activity - Apple Support

: If the fans on your Mac notebook computer run after you migrate data - Apple Support

Hallo it Eric from Kampala Uganda, I am having the same problems with my fans in my Macmini making a lot of noise and the machine gets so hot I adoption to slowing down especially when I am editing in FCPX just this morning I was trying to convert a movie clip using VLC and the it kept doing the same thing. Could Apple help us fix this issue please. Better said by Jobs " Let's be true to who are"

I updated ed to Sierra a quite a few months back. I had no problems, computer ran as before except for needing software updates. Then in Sep 2017, I got an iPad pro and decided it was time to try out the keychain sync over iCloud which I never had used before. I set it up on my iMac, Mac Mini, MBA, iPhone and iPad Pro. For the past couple of weeks I began noticing my MBA was running though battery life about 6 times faster than before and also that the fan was constantly LOUD, even after start up with no open software programs, and underside of the MBA was hot enough to redden my thighs in short order.

Today I was wondering if the overheating was the fan or the battery or both so I started searching and came across people with this problem after the Sierra update. So I tried all the posted solutions from Apple Support and forums.

Finally, the only one that worked, was force quitting the keychain access in Activity Monitor and then disabling Keychain sync in iCloud. It worked like magic. The fan is not audible in the least anymore and the battery life has held over the past hour (-7%) instead of dropping 30-40% an hour. And the underside of my MBA is no longer hot.

It would seem, at least in my case, that activating the keychain sync over iCloud was somehow related to high fan speeds, reduced battery life and my MBA heating up more than usual. By turning off these features, the problem was resolved. At least for me.

I have used a password manager program nearly 20 years so killing off the keychain sync was no biggie for me. It was more a convenience of being able to use Safari autofill across devices. I returned to using my password program set to launch in my preferred browser and using the password manager's app on my devices.

I hope my experience will help others.

I had this issue immediately after I installed Sierra on my MacBook Air. First I tried resetting the SMC and the PRAM. This did not stop the fans from constantly running. I then used Activity Monitor to see what was possibly overtaxing my system. I saw that the 'secd' process was consistently sucking up over 90% of my CPU usage. Others however said that this is normal after an OS upgrade and should drop back down after the computer finishes its initial photo and file scanning. I therefore let my MBA run plugged in nonstop for 36 hours straight and the fans just kept running while the 'secd' process continued to drain at >90% CPU usage. I also looked closer at the Activity Monitor and saw that tasks like photo analysis had their own processes separate from 'secd'. So I digged more into what the heck 'secd' was really doing with so much of the CPU resources. Long story short, I found that there is some glitch in Sierra that causes the macOS to get stuck on a process involving the Keychain and iCloud.

This is what I did to address this Keychain/iCloud issue that was leading to 'secd' overtaxing the CPU and triggering the fans to always be on:

-I went to Keychain Access and reset to Default (after I created a backup of my important passwords)

-In Activity Monitor, I used Force Quit to kill the process that involved the Keychain

-In Activity Monitor, I then Force Quit the process that involved iCloud

-In Activity Monitor, I finally Force Quit the 'secd' process. (I found that I could not simply Force Quit 'secd' without first killing the Keychain & iCloud processes first)

-After all that, I restarted the computer and the fans were finally off! I opened up Activity Monitor and saw that 'secd' was no longer hogging up CPU usage. Processes like photoanalysis were still running in the background at 40-50% CPU usage with no unwanted triggering of the system's fans. iCloud syncing and my Keychain were also functioning fine now.

I finally am able to use Sierra without my fans blazing out of control. Took me awhile to get this sorted out. Hope this helps save all of you some headaches and time until Apple is able to realize that there is this Sierra software glitch they need to address.

How do I make a backup of my passwords?

You can find the current keychain file in the Mac's Library folder. But as an update, you actually can solve the secd/CPU drain/fan overuse issue without resetting the Keychain. I discovered this when my iMac's fans started blowing uncontrollably like my Macbook Air after it was also upgraded to Sierra.

On my iMac, I solved the problem by the following alone:

-In Activity Monitor, I used Force Quit to kill the process that involved the Keychain

-In Activity Monitor, I then Force Quit the process that involved iCloud

-In Activity Monitor, I finally Force Quit the 'secd' process.

After this, the CPU usage returned to normal levels and the fans finally turned off.

"Kill the process that involved the Keychain and "that involved iCloud"

What does that even mean? Which processes should be killed, exactly?

I tried the Forcequit of the mentioned processes only to prove unsuccessful.

Investigating further, I happened to open iCloud setting and realized the keychain sync was set Off. I don't know when and how this had been checked off.

Nonetheless, switching Keychain sync back to On stopped both the 'secd' process running at high CPU% (now 0.0%) and my MBA fan blazing! I hope this helps.

This worked for me, but now I have to enter a password to get into my computer which is slightly annoying.

I updated to Sierra back in November and it has effectively made my laptop useless.

I have the same fan/heat issue and noticed task manager shows all 4 CPU's at 100% utilization running CommCenter, passd, and other kernal agents.

There is no clear reason why these are running. It's not an indexing issue as some forums suggest.

Battery life has gone from 6-10 hours down to less than 2 hours because the CPU's are constantly saturated doing who know's what. Response is slow, and the system sometimes freezes with the spinning beach ball. Maybe one of the new features of Sierra is a power virus...

I'm trying to revert back to El Capitain it's so bad.

Went through the process you suggest - no luck, fan still blowing loud ans continuous...

Thanks a lot. It worked like magic. It also increase my battery life. But I don't know if it's a permanent fix.