As reviewed earlier, after upgrading my Samsung Galaxy S5 to Android 5.0 (Lollipop), I started experiencing a big battery drain that would cause my phone to die in less than 8 hours, sometimes in as little as 5 hours (see screen left below).
At first, I thought one of the apps was causing the problem and waited for an upgrade. But after most of my apps were upgraded, the problem persisted. So as a last resort, I decided to investigate on my own. First, I turned off “Locations” (or GPS) and the “Location Services,” WiFi, Bluetooth, and just about anything that I thought would be using up my battery. Sure enough, that did fix the problem. But of course, none of my apps were very helpful since it didn’t know where I was and I couldn’t connect to anything.
After some process of elimination, I finally figured out the cause of the battery bug. It turned out to be a combination of the GPS, Location service, and WiFi. There is a switch that allows scanning of WiFi networks even when the WiFi is turned off. This is what is causing the problem.
To turn it off, go to the Wi-Fi Settings page (see middle image below), then touch the upper right for the pull down menu. Touch “Advanced,” to see the Advanced screen (see right image below). Finally, turn off “Always allow scanning” from this page.
If that alone does not work for you, try turning off “Google Location History” from the Location settings menu and touch “Delete Locations History” at the bottom of the Location History screen. Also turn off “Location” and turn it back on to clear out any caching.
Hopefully, Google will fix their Lollipop bug with the next release of Android so this is no longer a problem. But in the mean time, this fix will do the trick.