One of my MacBook had not been updated for a long time. It was working fine, but I decided it should catch up on OS/X updates. I updated the MacBook to OS/X 10.10 Yosemite. Immediately after I finished the update, I noticed the battery was draining rapidly. A fully charged battery lasted less than an hour. I updated the MacBook again to OS/X 10.11 El Capitan. The problem remained. This MacBook had Norton Internet Security installed.
To debug the problem, I checked battery condition – it was normal. To get battery condition, hold down Option key and click on the battery icon on menu bar.
Next, I ran Activity Monitor to look for processes that used up excessive amount of resources. To start Activity Monitor, hold down Option key and press Spacebar or click the search icon on the menu bar. Enter “Activity Monitor” into SpotLight Search box.
In Activity Monitor, I looked for processes that used up a large % CPU. The process SymDaemon stood out immediately. It used up 53%+ CPU and ran for a long time (i.e., a large CPU Time value). The above is a sample Activity Monitor output of a healthy system (not from the MacBook with problem).
I tried to update Norton Internet Security, there were no update. I uninstalled Norton Internet Security instead. Within a few minutes after reboot, I noticed the battery drain problem had stopped. To uninstall Norton Internet Security, open Finder and select Application | Symantec Solutions. Run application Symantec Uninstaller.app to uninstall.
Hope you find this useful. Good luck!
Poon
3/14/2016
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