Samsung s2 battery drain despite factory reset and doing factory reset

[HayleySmith75]

I have been having a problem with my samsung s2 draining the battery for about a week now, its draining 4 times faster than normal, I used to lose about 1% an hour and now its about 5% an hour even when its on idle and theres no apps running, no gps, no 3g and no wifi switched on.  I purchased a new battery thinking it was because my battery was getting old but same problem with the new battery.  I then tried factory reset but again same problem continues.  I have even downloaded an app that claims to help preserve your battery more but thats making no difference either.  The power saving is also switched on but its not preventing my battery from draining either. Is there anything else I can do to stop my battery draining so fast?

[drey_p]

Hi there

After the factory reset, did you reinstall your apps?  If you did, I would recommend trying again but this time without installing any of your apps.  It could be a app causing issues.

Also, when you did the reset, did you do it from the settings menu or did you use the volume key, home key and power button method?  The only reason I ask is that the second method gives you more options to wipe everything including the cache.

[HayleySmith75]

I did the factory reset from the settings menu and I reinstalled most of the apps I had before the problem started.  I will try the other method later if I don't notice any difference in the life of my battery during the course of today.

[drey_p]

If you do the second option, make sure you do both "wipe data / factory reset" and "wipe cache partition".  This will make sure that there is absolutely nothing left on the phone that could cause issues.

Once you have done that, don't install any apps - just see how your phone behaves.  If you don't have the battery drain, then install the apps one at a time and see if any of them cause any problems

[HayleySmith75]

Thanks, I have done that just now so I will wait and see what it does, I did manage to get a battery saving app to reduce my battery loss by 2% an hour as it killed all my apps while I wasn't using my phone today but its still losing more battery than before a week ago. So once its charged up again I will see how it behaves.

[drey_p]

The problem with a battery saving app on Android is often they have the opposite effect.  Android is very efficient at managing thing like memory and having a battery saving app constantly killing apps in the background can cause the apps to be reloaded over and over thus using a whole heap more battery.  I would personally uninstall the app as soon as you get a chance.

[HayleySmith75]

Ok, well I tried the hard reset using the buttons you suggested and cleared the cache and data and restarted the phone.  I have charged it to 100% with it switched off, its now been on approx 40 mins and now on 99% battery  with the wifi running in the background, which I would say is the normal rate of battery drain I have had for the past 2 years.  So hopefully problem solved. I will try reinstalling my apps one by one and watch the battery after installing, if I find one that drains my battery I will at least know which one I need to delete.

[drey_p]

Excellent news. I am pleased your phone seems to be behaving itself.  Hopefully you will be able to work out which one of the apps isn't playing nice.

Just another tip for you - modern phone batteries don't like being completely run flat as it can do long term damage to the battery.  Ideally try not to let it run below about 20%.  You're actually better off charging it more regularly say at 40% than letting it drop low.

[HayleySmith75]

I spoke to soon, I left my phone unplugged from a charger for 6.5 hrs last night and in that time it dropped 21% of its charge.  I have no apps installed so it can't be the apps causing my battery troubles, so what is it?!  Its driving me mad now.  My battery analysis overnight said that 95% of my battery that was used was used by device on standby (about 50% of charge was used by this) and the rest was used by android os and device idle.  I had the wifi switched on but that used only 5%.

I always charge my phone up when it gets to about 20% anyway, I had problems a few months back with my old battery where it was draining itself by about 20% an hour one weekend if you unplugged the charger by accident without letting it get to 100% but a factory reset stopped that one.  Nothing seems to be helping this time however.

[Retired-Laura]

Hi HayleySmith75,

Looking at all the things that you've tried, I think its time to try our repair process.

Find repair information here.

They'll be able to look at your phone and see what's happening.

Thanks,

Laura