iPhone 12 battery draining fast

Since the other thread on overheating has been run into the ground, I figure I should add this here as well.

I had 2 instances where my phone when idle or mostly idle (outside of quick notification checks), heated up pretty warm and dropped ~10% in 10-15 minutes (which is extremely fast) Outside of these times the battery is excellent and support ran diagnostics to find the battery in good health. Since the phone was hot, it leads me to believe something is incorrectly putting it under load. I fixed this situation both times by restarting the phone.

The first instance the phone was not on a charger, the second one it was on the MagSafe charger. Here are screenshots below showing the battery drop from 100% to 89% while still on the charger!! This happened over a 10-20 min period and the few apps you see open in the screenshot were opened after it had already dropped.

Dude this is fukked up! I have the same issue but not like this. The first days I figured out 5G drain a lot. I mean A LOT but after i turned it off the next night the lost was about 3-6% perfect for me. The very next night it started again. No apps in background. No email push. No background refresh. Like always, WiFi und Bluetooth on and data mode turned off.

i think I’ll go to the apple store

Odd, so we have people who can clearly see a difference between single-SIM and dual-SIM operations where single-SIM shows a more or less acceptable discharge rate. And we also have people solely operating on single-eSIM who still see problems and we have people who got their unit replaced and seemingly this solved the issue.

I have not been able to get anything useful from the iPhone console logs, they are notoriously messy and incomplete. But again a test clearly shows the difference in behaviour. Trying to raise it again with Apple through the support channel.

Your diagrams show something which i also found on my 12pro: After loading (it does not matter if up to 70, 80 or 100%) the iphone just needs roundabout 1% of battery in the first 2 hours. Thereafter the battery drain increases, so that my iphone needs 20 to 30 percent in standby while 6 to 8 hours in the night. I think there is a process which starts 2 hours after loading, but I have no idea which one it could be. My iphone is a dual-sim, but only the physical one is used.

For me it looks like this. My iPhone 12 lost about 30% during the night without any information about which app / process causes this drain. What's even worse is the fact that I enabled the power saving mode which, in theory, disables all the background processes of apps. I already replaced my iPhone 12 but my new unit is losing about 20% again. My workaround right now is to enable airplane mode, which seems to be working. Obviously it's not an fix. I'm using single sim.

Guys found a temporary solution. I have an iPhone 12 solo sim. Every night I lost like u guys 15-30%. Now I’ve lost nothing! Just go into airplane mode and yes U can leave WIFI turned on. it helped for me. After I woke up I had still 100%! Next week I’ll go to the apple store and report this ****!

I tried all the things on your list with the same experience (except point 7, I only use nano-sim). Now I tried the complete reset and install everything new, not from my backup. This seems to help. Until now I did not install any additional apps. My iPhone needed 13% of battery power in more than 16 hours in nearly standby. It will be interesting what happens when I install allthe apps I need.

My issue appears to miraculously solved itself after circa one week. The only setting I have changed on my device is background refresh but when I did this, it didn’t seem to make any difference. Unfortunately I have no idea what has caused the change, but if I can work out what has lead to the improvement, I will be sure to let you know. For background, I am based in the UK with 5G Auto turned on (albeit I do not live in an area that has 5G) and one sim. I was experiencing approximately 20% battery drain when idle overnight and now no (or very minimal). Will keep you posted.

This is the same with my iPhone 12 pro. When using both line battery drain in standby is about 10% - 15% per hour. The phone barely lasts a day. Battery life is like my iPhone SE 2020. When I turn off the second line the battery drain stops. I had the same setup on all my prior iPhones as iPhone 11 Pro and pro Max with no issues. Here you can see my results while playing with second line on and off. Not being able to use the second line or having it to turn off most of the times is no solution.

Hi group,

I have exactly the same issue as all of you - terrible, absolutely terrible idle battery time

My Iphone 12 is literally discharging by its own in front of me without even doing anything on it.

I have the regular Iphone 12 64GB black, German operator - Deutsche Telecom, just 1SIM (no eSim). I always start with a clean install no backup restores and spend around a day to optimize it to the fullest.

Background apps are disabled, location settings stricktly limited to what needs to be used only, mail optimized, returned to LTE only (no 5G), no fitness tracking and bloatware like significant locations etc.

With all these settings and my phone calls my old Iphone X would get me around 3-4 days of casual usage before I need to charge it.

With the Iphone 12 now ......... only sitting there without even talking on the phone max is 1 day!!! I charge it in the night and it can barely survive with 20% battery till end of the same day. If I leave it overnight it would simply turn off and discharge the battery completely.

Apple please fix your mess immediately!

Below is a complete discharge for 1 day with just idling - 1 hour use to turn on the display and see how it is draining the battery .......

I tried no wi-fi, battery saver, DND mode ....... nothing works. Below is even visible this is battery life with battery saver turned on in the beginning.

If I enable 5G and start using my phone probably will need to walk with power bank.

For your info guys, here a screenshot of the battery usage I took of my 11 Pro (got it September 2019 and battery peformance is still 99%)

I did that because some here were claiming that over night there was battery usage and it was normal the drain... lol make me laugh.

So I began to charge around 7pm.

Unplug it at 8:50 pm it was 100%

Left it over night

and it's only around 11am the day after that it dropped under the 100% bar.

On my 12 pro, when I had passed 12h without charging it, on idle, without any SIM, in airplane mode, background apps off and energy saving mode... 50%... in 12h, doing NOTHING, like in 'not a thing'... and this, was the same by Day or by Night.

I have returned my 12 Pro, and I will wait until they admit there is a problem before thinking buying one. I have lost confidence. But I'm pretty happy with my 11 Pro for now.

Apple service was very good with me, and even offered me to replace it. But I did not want to, as I didn't knew if the problem would still be on the new phone, and going over the delay I had to get refund. Because I did not want to have a brand new phone's battery or circuitry replaced when they find out. Lets hope it's just software though... for you guys that still have it.

I don’t run widgets on the Home Screen, only on the today screen.

here you can again see the impact of my 2nd SIM. When I disabled it during the night the drain was significantly less (but still not good)...

Absolutely right! Here I read that there is a suspicion of a hardware problem ( modem ) I think it is not logical, because with a problem like this we have a very small percentage of users ! There is hope that iOS 14.3 will solve everything. My ipnone 12 pro loses on average 30% per night (all services are turned off)

I’ve fixed the issue for myself. It definitely seems sim related. This morning (00:30) I went to bed with my phone at 95% I put low battery mode on and went to sleep. When I woke up 7 hours later my battery was at 65%

this is awful I thought and after googling I found this discussion. I have a iPhone 12 pro with one physical sim. 5g isn’t not available in my area.

I turned off my phone and restarted it. I received a tonne of text messages I reckon they must have been sent over the past few days and my battery now seems not to be draining quickly anymore see the battery for the last hour and a bit is flat. It used about 1%. I will update later tonight if it remains good or back to bad.

definately seems like to me a modem bug

best of luck all.

Picture of my nightly discharge ... I specifically included all the services, the result is the same ! The problem is unambiguous in the network (average discharge 3% per hour) only one question is how it happens that users with such a problem is not a large percentage !🤔