Why has my battery life halved having moved from PAYG to contract?

[AliStan]

When on PAYG my Samsung Galaxy S3 mini battery lasted 3 days or more.....ever since I've moved to a Contract SIM it barely lasts 24 hours.  I'm not using it for internet, barely even for phone calls, mostly for text.  My usage habits haven't changed since it was fine on the PAYG SIM.  All that has changed is the SIM card.  I've tried the obvious, WiFi, GPS, Bluetooth all turned off and it's not made any difference.....HELP!

[drey_p]

It could be that you battery developed a fault or wore out at the time you swapped from PAYG to Pay Monthly.  It may be an idea to download a free battery monitoring app such as GSam and keep an eye on things for a few days to work out what exactly is using up your battery.

[AliStan]

I loaded up GSam yesterday and most of the battery seems to be being used by the Kernal (Android OS) roughly 35% of battery?  Sorry, I'm not technical but assuming OS is Operating system I'm guessing there's not a lot I can do about that......although will this have changed settings by switching to contract?

Battery is only new from Xmas so would hope it's not worn out yet!

[hrym]

The problem with battery monitoring apps is that they only show the proportion of usage.  What you have is about right for a device that's idling.   Use if a lot and you'll find that the screen will account for 50% or so.   What we have established, though, is that there isn't an app that's using more power than it should.

It's slightly unlikely that the switch to contract is anything other than coincidental, as the phone will be attempting to connect and use data pretty much as it always has (unless ndj's suggestion has produced a result).

Assuming you haven't added more apps and aren't simply using the phone more, another possibility is that the battery is coming to the end of its life.   Are you also noticing shorter recharge times?  If you look at the battery, does it appear swollen?   Also, if you've allowed the battery to go flat at all, this will shorten its life.  Normally, you should expect 500-1000 recharge cycles (though this is proportional if you simply top up), which equates to about 2 years of daily use,

[Northern-dj]

Arrr with you now picking the contract wap it will now log in

Yes the issue will be the kernal as the phone is working hard trying to conect to a network it carn't

on the S3 we had a issue that was with Vodafone and this is why the network touble shooter came about

the phone was trying to log on to the network and couln't thus draining the battery

it also may be a combination of things as the others have said

with finding the problem on a phone it biols down to a proses of elimination

please keep us informed as to what happens

[hrym]

A phone that's on a weak connection will use more power s it boosts the radio, but I didn't know that there was a data connection equivalent of that.  Thanks.

[Northern-dj]

This sounds familiar
Check your APN settings you will find that there on the pay as you go settings so even tho your not using data the phone is trying to log in and can't
This can use power one way to check is shut your mobile data off
When you put your simple in it should of revived a update text this adds the APN but you might still be on the pay as you go APN make sure you have a green dot in the right one

[AliStan]

Thanks.  Just looked and only option showing was contract but it wasn't selected so have tried selecting to see if it makes a difference!

[63johnw]

There is the old try a factory reset option.

Whenever I start having battery issues its the first thing I try and quite often sorts it out.