Unusual battery drainage and warming up after macOS Sierra update

Is Siri running at all with the new update?

i turn mine off when i'm not using it. Remember, Siri is always thinking and searching so when you put in a request you are not waiting a long time for search results.

Since Siri is always working, your laptop is being used more, which will use more battery.

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 battery drain and 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:

-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. Battery life went back to normal. iCloud syncing and my Keychain were also functioning just fine.

Took me awhile to get this sorted out. Hope this helps save you some headaches and time until Apple is able to realize that there is this Sierra software glitch they need to address.

I checked my secd usage, its 0% CPU usage.

Battery problem still persists.

If Activity Monitor shows no runaway process and the various spotlight indexing and iPhoto pic analysis has fully completed with the Sierra upgrade, your rapid battery drain may be hardware related. Just prior to my Sierra upgrade, my Macbook Air suddenly went from lasting several hours to draining down to zero in about 40 min. I took it into an Apple Store and they found that the battery needed to be replaced. They did this for $129 and this solved my issue.

So it may be coincidence that your battery is dying around the time of your Sierra upgrade. I recommend making a Genius Bar appointment and having them run a check on your battery. If the battery is fine, their diagnostic system may likely tell you what your actual issue is.

None of the fixes I have read about seem to work. I am taking my MBP to the "Genius" Bar to have then uninstall the crappy Sierra update. Seems to be the only remedy! ALSO SEEMS APPLE IS REALLY LOOSING THEIR TALENT! How you the release such a horrible update without realizing something so basic!