Help Nexus 7 2012, Android OS 4.3 battery drain

[eodeo]

I had this problem for some 2 weeks before I figured it out. Here is what I experienced, and at the end you will find how I fixed it.

I noticed Android OS using large amounts of battery power, effectively preventing tablet from going to sleep. Usually, the screen would the #1 user of battery, but after an hour of inactivity - with the tablet screen off and all applications closed- android OS would become #2 if not #1 power user.

I googled, tried many things- everything short of resetting to factory settings and nothing worked.

Something seemed to prevent tablet from going to deep sleep and drained my battery rather quickly. Not even using the tablet in "safe mode" alleviated this problem.

By accident I noticed that this would not happen when I traveled away from home. Android OS would be distant last or second to last power user, like it should be, instead of first or second of normal usage at home.

Turns out the problem was with my internet router. I switched it from no security to WEP secure password about 2 weeks ago. I switched it to WPA today and Android OS settled down and stopped using battery at unpleasant proportions.


For whatever reason Android 4.3 really doesn't like WEP security and it is preventing the OS from going to sleep. Hopefully, someone else experiencing this problem will find this information useful and will help them get peace of mind and maybe even some sleep too.

 

[John Bean]

Interesting. I had a similar experience with my Nexus 7 on its original 4.1 version that made it run hot and kill the battery in a very short time, and a bit of Googling revealed a number of users who had discovered that they had similar symptoms with some routers but not others, and I discovered a "fix" that worked for me.

I had read that Google's attempt to reduce battery consumption on wi-fi caused problems with some routers, causing infinite loops that held the device awake and had the precise opposite effect of that intended by the programmer. Un-checking "WiFi optimisation" (under "Advanced" in the wi-fi settings) was all I needed to do to to fix it, it has worked perfectly ever since (including 4.3) giving many days (well, weeks in fact) of standby from a single charge. I can't see how the "optimisation" could make it any better to be honest.

From your post I can only assume that the "Wi-Fi optimisation" incompatibility with some routers is also dependent on the type of security in use, so changing one or the other can have a similar outcome; personally I'll stick with better security and pass on Google's (failed) attempt to "optimise" it