Battery drain & no hardware issue, what could it be?

[iMore Question]

Battery drain & no hardware issue

I have an iPhone 5S which is on iOS 9.2.1. The battery drains extremely fast while the phone is not is use, screen locked, the drain is much lesser during normal usage. Also, the battery stats page keeps saying that the battery stats will occur after using the phone for a few minutes all the time. The phone also says that this iPhone has been plugged in since last charge, but the time counters since the last full charge are fine. I had the same issue on iOS 9.2. I tried a hard reset, and a clean iTunes restore, I am out of ideas, what do i do?

I called apple support and they ran a diagnostic on the phone, turns out my battery has only 13 cycles on it and is grade A ok.

They want me to bring it in for a hardware check anyway at the country of purchase, which is 7000 miles away from where I am now

 

[mr_coldharbour]

Re: Battery drain & no hardware issue

Probably some background activities occurring. Try turning off Background App Refresh, Location Services, and set your emails to Manual rather than Fetch or Push. Sign in/out of iTunes account on the phone as it could be a bad process/download stuck in the back trying to download from the cloud. Are you using iCloud? If so, try turning it off see if it makes any difference. Anything iCloud (including Photo Library), off. Seems like something is stuck in the background. Does your phone get warm even when not in use?