iPhone 12 battery draining fast

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 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.

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.

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 ****!

7% overnight is in the NORMAL RANGE. If it bothers you that your phone is working as designed get rid of it and get a basic flip phone that will go for a week on a charge. Or follow the best practice of charging the phone overnight, which is better for the battery as well as keeping Wi-Fi on.

Your phone is constantly pinging cell towers all night to check for incoming calls and SMS messages, so battery use while idle is expected.

Further, have you checked Settings -> Battery to make sure no apps are unexpectedly using a lot of power?

My battery drain was about 30% during the night (approx 7hours).

2 days ago, I reset network settings and battery drain is about 13-14%... so a little bit better but I am still not fully satisfied

I have only physical SIM, 4 bars of LTE network signal, connected to WIFI

My second iPhone 7 (85% battery health, the same apps installed) has about 5% battery drop during the same period.

There are always things going on, and they aren’t the same things every night, so you shouldn’t expect the battery drain to be the same every night. Here are just a few:

• Incoming text messages
• Incoming iMessages and messages from any messaging apps you use
• Push and Fetch email
• Notifications from apps
• iCloud sync for any items that you have set to sync
• The phone pinging the cellular network to report its position every few minutes
• Data updates from apps such as weather, stocks, news, podcasts, shopping apps, calendar, etc
• Any apps that do housekeeping using the background app refresh feature
• Incoming visual voicemail messages if you have Do not Disturb enabled (if you don’t, any phone calls you get)
• Multiplayer game updates (e.g., Words for Friends)

Not fully aware how iOS internally handles this, but at least this is what I did last night (remove widgets and swipe all apps up and close all safari tabs) and this had a significant positive effect on the battery. On the iPhone11Pro and 8 that I'm testing with this is (as expected) not required.

That is the question of many here. It appears to be a software problem.

I've already replaced my iPhone 12 and had the same problem with the new one.

I think the only thing we can do is wait for an update.

Hi, my iPhone 12 Pro has the same battery drain when idle. It seems to be related to the SIM.

No SIM = Battery drain 2%

SIM inserted = Battery drain 25-50%

I read that iOS 14.3 (beta 2) solved this issue for some people. Can anybody confirm this?

Yesterday I let fall my battery to 0.

Then fully charged.

In the night the battery drained 17%.

At home I will activate Airplanemode with WLAN Call.

there isn’t a high drain in this mode until it’s fixed. 🤷🏻‍♂️

So I’m having the exact same issue; approx 4-5% per hour drain overnight. I’m on my second device from Apple but was able to keep the original device and have been testing a few things out (nothing has solved it but there’s been some interesting quirks). Both devices have the exact same issue and it’s consistently repeatable day after day. I tried restoring from back up, setting up as new, unpairing watch etc. But no improvement.

Im running one sim (physical), I’m on the O2 network in the UK

On receiving the 2nd phone, I removed my sim from the old phone and put it in the new, but left the old phone set up on my account (just to rule out the watch theory, my watch was still linked to the old device for now). The following morning, with the original phone left idle since around 12PM, it was still in the mid 90’s, while my new phone had depleted to 60% and had been off charge for 12 hours less.

I then wiped the original device, but set it up for one of my family members, including using their sim, to see how that went. I charged it to 100% at 3 in the afternoon. The following morning, with a small amount of usage (around 45 mins) throughout the previous evening, the phone was now at 93%

This is obviously in line with what I would expect from a perfectly working phone...

What really gets me is; the different sim I was using was a Tesco sim, Tesco use the same network in the UK as O2, yet one seems to be causing horrific battery drain and the other doesn’t.

Appreciate that this is not unique to my network around the world but I thought this was interesting to say the least!

Contact Apple support, insist on a senior advisor, refer to this thread and indicate that you know there are many others complaining about this, make clear that you tried the obvious (factory default without restore of backup, clear network settings, etc) and insist on deeper analysis.

askar_berlin wrote:

I noticed that my iPhone didnt loose a single percent of battery power in about two hours ....

After loading my iPhone for some hours it takes about two hours before the draining begins. Thereafter the drain is constant. Loading for a shoort time does not have the effect. Did you load your iphone before you noticed that?