any ideas on what to do ?
I would just factory reset if it was me!
But you could try these first:
Clear Google search history
Clear System process
Clear the cache for all applications
Clear Google Maps search history
Clear browser history
Clear the clipboard data
Clear Gmail's search history
Clear market search history
And after that turn it off, take the battery out and wait a few seconds. Then, place battery back in and turn the phone on.
Let it run for a few hours and then check to see if Android System is still consuming so much battery.
Let us know if that helps you or not.
Like I said, I would just factory reset to see if that takes care of that.
Anyway just let us know.
Sent From a Galaxy S4 Away!