iPhone 12 battery draining fast

I’ve been doing some experimenting. My config is a regular 5G SIM with VoLTE and VoWiFi and a 4G eSIM with only VoLTE.

ive now disabled the regular 5G SIM and switched off VoLTE on the eSIM and I think I saw a major improvement in battery life (although I need some more time). I then enabled VoLTE again on the eSIM but kept the 5G SIM switched off and still the battery consumption seems normal.

This is odd, I’ve been using the same dual-SIM setup in an iPhone 11Pro without problems and in the iPhone12Pro 5G is disabled currently when dual-SIM is used (dunno why) plus the 5G SIM was set to 5G on-demand anyhow.

So puzzled what is wrong here, I need more time to get more definitive results but maybe others can experiment with this too.

Confirmed now, my phone only consumed about 1% per hour during the night, so about 10%. Still more than I would to see from a complete idle device but acceptable and in line with what I’ve seen on older devices. I forgot to mention that I also toggled “low data mode” on, on the remaining 4G eSIM. So now it’s time to check the low data mode and the second SIM to see what exactly triggers the insane drain overnight. I’m curious to hear the experience of others with these tips.

Hey guys, I have the same issue as well. My battery loses 15% capacity over night. 5G is deactivated and still. I contacted the apple support, they analysed my iPhone 12 pro and everything they told me was that the iPhone is fine. If this is normal in their eyes, I will return the device. My previous phone was the samsung galxy s8 and it lost only 2-5% battery over night.

Now, it seems to be fine.

Close to 24hrs, still 62% batterie (less usage).

This night about 5-7% (corona-contacts use the most...)

So its about 0,65% per hour.

May everyone with the problem should try the hard-reboot.

I strongly but politely ask to refrain from cheeky responses. Of course we know you can charge a phone but a) many choose not to charge lithium batteries while sleeping and personally I think that is a good habit and b) many are not capable of charging overnight for whatever reason and c) it's beyond the point. The point here is that there is a clear battery drain and I think we as the community all benefit from it when we can identity the issue and have it resolved. iOS and iPhones should and can do much better and the iPhone11 clearly demonstrates that. Also, my tests clearly indicate there is an issue. Enabling low data and switching of my second SIM has dramatically changed the discharging curve and actually now shows a more normal discharging behaviour where there is a clear correlation between usage and rate of discharge. When the battery drain is present there is no such relation: the phone just discharges at a fixed rate, despite the actual use. That is not normal and it's perfectly legitimate to complain about it.

We're not complaining just to complain, at least I'm not. I'm complaining and we're putting efforts in it to come to the root cause and have it fixed.

I tried using low power mode overnight having charged to 100% - by morning I had only lost 3% battery. This sounds great however, to achieve this, I stopped all apps background refreshing, and used low power mode. To compare, I charged my iPhone 8 Plus (which battery health says the battery is significantly degraded) to 100% did not stop background app refresh and did not use low power mode & lost 3% battery rate. I may try the hard reset that others have mentioned & will let you guys know how that goes!

I tried this yesterday & it seems to have solved the issue for me. I only lost around 4% overnight without needing to use low power mode etc. I’d recommend others experiencing the rapid idle battery drain to hard reset!

Same issue here. I've owned every iPhone that came out since 2007 and this is the first time I have experienced something like this. Losing 18 to 20% on standby at night time which isn't comparable to previous iPhones that would only lose 0 to 2% overnight. Wifi and Bluetooth are both turned off. No apps running in the background. App refresh turned off. Mail push and fetch turned off. Tried rebooting. I factory reset my phone twice. And the battery drain is still there.

However, I tried turning on airplane plane mode overnight and the battery didn't lose a percentage of battery. So I reset the network and battery still drains. So this is a perplexing issue.

LOL that is what I will do when it's my main phone. Where did you read I did not want to recharge it during the night?

But have you check the image I posted at least? Have you seen the drop, while I'm not using it? On airplane mode...

What I worry is that when I will be using it for real, it will not last half the day at this rate. Not even talking of the chance it is a defective unit that could blow out due to a short in the circuits.

I am trying to put this problem out loud so someone take care of it. If it's a setting of the phone, it was not affecting my old 11 Pro. BTW, I used the new feature to transfer my old phone on the new one by "Bluetooth?". Not sure how it was transfering, but it asked to keep phones near each others... I assume Bluetooth

Thank you guys, I will do it.

Look like since it is in energy saving mode, it is not draining much. Where Airplane mode failed, Energy Saving (with Airplane mode) is doing it.

Next step tonigh is the Hard-Boot.

Hi

i have same issue

example last night la 11 pm i had 41% and in the morning at almost 9 am it has 8%!!!

and i did not use the phone overnight

background activity none

and i turn the wifi off when I sleep completely

I'm having the same drain issues using dual-SIM setup. When idle with dual-SIM its about 4% battery an hour of battery loss. Without dual-SIM it is about 1,5% battery an hour of battery loss.

I tried several other things as well like reinstalling the device but for now it just seems to be the dual-SIM that is causing all the battery drain.

Hi Busaku, Odiebla and ApplePears88. Thank you very much for your support.

I did an hard-reset (boot) and it did not fix the problem. And I was wrong about the energy saving mode, it was draining the same level. When I checked the graph, the yellow was dropping at the same rate as the green graph.

I'm testing tonight the Battery management. It's activated on my phone actually. I will deactivate it, hard-boot (will always do it from now on when testing things) and see if there is a change. Saw that playing with it for some people did it...

After that, if it still does drain the battery the same, I will erase my phone and see with the plain OS without importing stuff from my old 11 Pro...

That will probably be my last test before I go get a refund on my phone. I'll probably buy another one later when they fix this problem either on the iOS or Hardware...

I have the same problem on iPhone 12, and I think that problem is related to cellular networks. When I remove sim-cards from phone i have normal idle power consumption - about 1% in two hours. But when I insert SIM-card (or activate esim) - battery drain is beginning - about 3-4% in a hour. And this draining happens even if phone is connected to Wi-Fi. I have iPhone 11 and everything is okay in the same wifi network and the same sim-card.

P.S. I have try reset and setting without backup, but it have no effect.

I actually replaced my iPhone 12 because of the standby battery drain (up to 30% at night WITH energy saving mode). Yesterday I got a new one but last night it lost 20% again (with only 5 Apps installed). Tonight I will hard reset it and don't install anything to check if there's an app causing this issue. If the problem persists I'm thinking about buying an iPhone 11 Pro, it's so sad.