Try this if KitKat Update Causes Battery Drain Issues

[wazz]

I found a  helpful Verizon Galaxy S4 post in another forum at,

Android Forums at AndroidCentral.com

This post, by "Leo G" (quoted below) identifies how to clear your cache. If done correctly, clearing your cache will not affect your present applications & phone setup (i.e. you will not need to re-install your applications and re-enter your various settings).

Another user on the same forum, same thread, named, "Mahler9" reported that after he performed this operation, his overheating disappeared, and battery life became better than pre-KitKat.

I was noticing increased battery drain between charges after I updated to KitKat.  I performed this operation and my battery life between charges appears to have been restored to pre-KitKat. This may not work for every Galaxy S4, because the issue could be related to a rogue application or some other combination of your specific phone or application settings.

This is worth a try before you "throw in the towel" and perform a full factory reset.

"Try clearing the cache before the full reset.

Power the phone down, ie: turn it off

Hold the up volume, power, and home button at the same time. When you see life let go of the power button

and then after you see small blue lettering in the upper left hand corner let go of the other buttons.

Let it finish

Use the volume control to get to the clear cache line. Push the power button. It will do it's thing and wait for the next action.

Do this 2 more times and then using the same technique choose reboot and let the machine reboot.

Check and see if it fixed it. If not, bummer. You may have to do a full reset."