How to disable AddressBookSourceSync in El Capitan AddressBookSourceSync continually prevents idle sleep.  I don't use address book syncing and in previous versions I used just to delete the app.  However this is now prevented by System Integrity Protection.

Is there an approved or easy way to disable the app (via a launcher or property list or something)?  Or do I have to disable SIP remove the app and then (if I can) re-enable SIP?

EDIT

It occurs to me that because SIP acts only on the boot disk, it is easy to delete the file by just booting from another disk (eg USB) and accessing the main HD from there.
Not sure if this is really a good idea, but you can run this (as yourself, not root) in Terminal:

launchctl unload -w /System/Library/LaunchAgents/com.apple.AddressBook.SourceSync.plist


FWIW, I had the same problem and even after following the instructions in Tetsujin's link, turning off all Contacts accounts in System Preferences, logging out of iCloud, blowing away the AddressBookSourceSync directories in ~/Library/Caches and ~/Library/Application Support, and of course many reboots, I could not get AddressBookSourceSync to stop blocking sleep. This command “fixed” it. AddressBookSourceSync no longer runs and pmset -g reports nothing preventing sleep.

You can undo the effect with this command:

launchctl load -w /System/Library/LaunchAgents/com.apple.AddressBook.SourceSync.plist