iPhone 12 battery draining fast

So, yesterday I finally decided to configure my eSIM on my iPhone 12 and observe the idle drain overnight. Using 2 phones wasn’t working out for me.

Having this phone for 4 days now, somedays I woke up in the morning with 4%, 5% and 14% drain overnight as well. I couldn’t isolate the cause for 14% drain outlier though, I kept WiFi on, and maybe sub-par cellular reception that night. I usually turn off the background app refresh as well. This was with single SIM.

Coming to this experiment, I saw 5% drain overnight, from 10:30 at night until 7:30 in the morning. The settings were similar except the WiFi was turned off this time around. As for cellular reception, I had 2/4 bars on both the SIMs, with the secondary SIM occasionally latching on to 3/4 bars. The battery charts are pretty much flat throughout the night with no apps consuming power listed below.

Should I be satisfied with this drain with 2 SIMs configured? It’s my first iPhone and what I had gathered online, the standby optimisation in iOS is exceptional with 1-2% drain overnight, for most users.

But please do either go to store or talk to Apple support do that they are aware of the problem. They will probably try to tell you it is normal or to do things such as reset phone, none of which will work. Just insist on speaking to senior support staff, then keep on with them until resolved.

No it doesn't for me ...

Indeed it seems to have been solved temporarily for me with iOS 14.4 but the issue is back since 14.5 or 14.5.1 ... And 14.6 doesn't solved anything.

Here is some screencapture from my iPhone 12 Pro Max and with girlfriend iPhone 11 Pro Max, both are now in 14.6 and were this morning in 14.5.1. Her iPhone is my previous one so the battery is already "used" ...

The captures with white background are mine and the ones with black background are her.

I think the picture speak by themselves, I almost don't use it and it depletes (with an almost constant slope) faster than her while she uses it :'(

At 2:30pm:

At 6pm

The only time when it doesn't abnormally deplete is during the night, with do not disturb and night mode activated (not the airplane mode).

ColinFromSussex wrote:

[...] They did send me a replacement [...] but it was exactly the same. IOS update fixed it. [...]

take it back and insist that Apple raise it to highest level, or demand a refund. Apple DO know of this problem as they have quietly fixed it in IOS releases.

Why encourage people to ask for a refund or something else and say that it has been solve via an iOS update for you?

I don't get the logic.

I have an iPhone XS running iOS 14(.6) and I also have this battery drain issue. During the day too. I however have narrowed the search for the cause down to the following:

• If my phone is in a Wifi at home together with my Macs, it drains fast (need to recharge twice a day).
• If I put the phone into my guest Wifi, which has no other devices on it and only internet connection, it does NOT drain. Neither does it when left on LTE (but still uses more power than when on guest Wifi, which makes sense of course, because the radio needs more power).

I already tried running no 3rd party software on the Macs, Catalina vs. Big Sur, and various other options. Initially, having iMazing running or not on my backup server made a difference, but it wasn‘t that. I filed a Feedback with Apple, but well.

Sorry I didn‘t read all 169 pages of this thread before posting.

Hi all, the battery drain in my iPhone is now much better than last week. What I did:

• complete reinstall (two times) and letting it run without a reinstall of the backup > no change
• shutting off many unnecessary background activities > no change
• complete reinstall a third time, installing the last backup and while running I pulled the SIM card and several seconds reinserted it. After this action, the heavy battery drain is almost gone. But I don't know what really did the change.

Before, with this heavy drain the battery app sometimes showed non stop use of the flashlight while it had never been used at all … very strange.

Hope for a cure by Apple!

Iphones shouldn’t generally drain a single percent overnight whether just unplugged from the charger or even used before sleeping. The iphone 11’s would never drain overnight mo matter what the circumstances are. Even if there was some background activity a maximum of 2-3% should drain. More than that is just not normal.

For me the issue remains SOLVED even weeks later. iPhone XS, 3 years old, daily use, battery at 85% efficiency. With light use, I have about 40% battery left at the end of the day. I rarely need to recharge before evening. Location Germany, providers Vodafone and Telekom (dual SIM).

The one thing I did, as explained earlier, was to disable the "show this iPhone on Wifi" setting on all Macs in the same network on the same Apple ID, and quit the iMazing application on my Mac server during the day.

If by idle you mean locked, Wi-Fi is off when the phone is locked, so it isn’t Wi-Fi that is draining the battery.

What apps do you see when you go to Settings/Battery that are using the most energy?

After a hard reset it feels better

Did you try the restore yet?

I have a 12 Pro Max.

It loses about 3% over six hours when idle and on WiFi.

helder33 please try to call the support and provide them the information. This will help for sure.

Are you using dual sims? If not, then which sim are you using in single mode? eSim or physical sim?

I experience battery drain in dual sim mode but it stops in esim mode.

That's what I was thinking. Wouldn't hurt to try a new SIM or switching to eSIM.