iPhone 12 battery draining fast

After a couple days of experimenting.

Let me give you scenarios/examples with no regard to any other settings other than those mentioned being turned on or off.

iPhone 12 Pro running iOS 14.3

SIM card installed, WiFi on, Cellular On, Bluetooth in Standby (Turned off in CC to disable new connections, but still enabled)

Battery drops between 15 and 30% over an eight hour time frame while not being in use. (This was the case for a couple days, until I realized something was clearly wrong)

SIM card installed, WiFi off, Cellular off, Bluetooth standby same as before

Battery drops around 10% over the same time frame (Better, but still not satisfying)

Now get this!

SIM card taken out, Wifi on, Cellular off, Bluetooth same as before, I also turned Airplane Mode on for the sake of it

Draining between 1 and 3% , over the span of 8 hours.

I know, it seems absolutely silly to use an iPhone without a SIM card, but as long as this bug is not fixed taking out the Sim card might be your best option to prevent your battery from draining over night. Or you just simply keep it on a charger. Keeping the SIM and at least turning off WiFi and cellular or putting the device into airplane mode should make the battery drain a little less too.

Some other things you might want to switch off, if only to test for a couple days to see if battery life improves and slows the drain. Keep in mind, you can disable everything temporarily and don't have to worry about anything breaking. If something needs a certain thing enabled, iOS will most likely give you a prompt anyways. You can go back and enable everything again, but until a version of iOS 14.3.x or 14.4 is released that addresses the those kind of issues, it's the best and to be frank, the only thing you can do.

• Location Services > System Services. Be bold and turn off EVERYTHING. Toggle the status bar icon (the switch on the very bottom) so when you slowly enable them one by one again, you can keep an eye on what triggers the location to update. With the status bar icon on, you can check and investigate closely how and when a certain service is updating. I found the Find my iPhone location feature updates like crazy.

System customization also updates in the background constantly ( if you turn it off, Dark Mode/ Appearance will still be able to work in sunset/sunrise mode, night mode however will work only when you put it on a custom schedule, and optimized battery charging will not work (even the option itself in the battery menu is enabled) if you have Significant Location and/or System Customization disabled).

• Put Bluetooth into standby so it stops searching for new devices (Toggle it via Control Center so the icon becomes white.)

• Turn off 'Ask to Join Networks' and set 'Auto-join Hotspot' to Never in Wi-Fi settings to stop the device from constantly checking for sources, notifying you and trying to connect to other routers.

I don't mention any of those things like turning off Background App refresh, dimming your display etc as those can be found in literary every 'iPhone battery savings' video or article.

It is clear that the issue can be pinpointed to the cellular modem, which can only be put into completely pause if there is no SIM card in the device. Airplane mode alone does not seem to fix the issue fully nor does turning off Cellular data help much if anything.

I MIGHT JUST HAVE A FIX FOR Y'ALL WHO ARE FACING MAJOR BATTERY DRAIN WHILE YOUR DEVICE IS ON STANDBY !

So I just bought a regular iPhone 12, 128 GB variant few days ago and I was really happy with the design, UI, features and the premium looks of it. Until I found out that my device just lost over 20% of battery under 8 hours while I was asleep. I was disappointed and nervous that I might have got a defected piece just like everyone in this thread. I could be a good example for this problem since I'm a brand new iPhone user who switched from Android. So yeah, I didn't have to backup anything from my older devices. I used it as new as it can be but still the battery drain on standby was inevitable. I messed with the setting in every possible way to find a solution before I head to apple store for help. Some of these changes that I made would not be really necessary but I suggest you try it so it can get the same response as I did.

1. Hard reset your iPhone by tapping volume UP once and DOWN once and hold the side button until you see the apple logo and only then, you should let go of the side button. Watch on youtube if you want to know how exactly it is done.
2. Once booted, remove your sim, backup all your files and go to settings < general < reset < reset all content and settings. This is will reset your phone back to factory settings. (Highly recommend you do this)
3. Now you have a fresh iPhone just like it came out of the box. You can insert your sim now. Go to settings < mobile data < mobile data options < switch it to 3G. (I strongly believe that this particular battery drain issue has something to do with the latest modem that's messing up with the network settings so until Apple cares to release an update, I suggest you prefer this alternate method)
4. Go to your iPhone storage and delete all unnecessary free Apple apps that you won't be using in the near future. (You can skip this if you want)
5. Go to settings < privacy < location services. Switch all available apps location request option to "ASK". Then go to system services and disable all location request for ones which you don't need. As for me, I disabled literally all the options except "Find My iPhone" and "Networking & Wireless". Make sure you turn OFF "significant locations" and all 3 product improvement options.
6. Scroll down in settings and select Mail < Accounts < Fetch New Data < Turn off "Push" and select all the available options to "Manual"
7. This is absolutely not necessary but you may keep this as a last resort. Remove all the widgets that is available on the far left of the Home Screen and change your wallpaper to plain black that is available under Wallpaper options.

*These are all the settings I tweaked personally. All my notifications and background app refresh are turned ON by default. I never made any changes to those settings but you can always turn off those options per your preference.*

So this was my final test. I charged my phone to 99% and kept my WiFi on and Mobile Data OFF and left it on my desk when I went to bed. I slept at 11 PM and woke up at around 8 AM. Guess what ? Voila ! My battery percentage remained the same 99% ! I have been using the phone non stop since I woke up and its doing much better than my One Plus 7 pro. I never noticed any battery drain on standby but I noticed the battery consumption was a bit more when it reached 80%. However, it is pretty impressive given the 2815 mAh capacity.

I highly recommend you follow these instructions so you may feel a bit relieved from all the anxiety and stress this issue gave you since you bought the phone. I hope this really helps all of the users who face this issue. Peace

Hey there

im experiencing the same issues with my iPhone 12. at first I thought it’s a hardware issue and got a new one as refund.

but with a new phone- same issue I’m sure, it’s not on the phone itself.

obviously I turned off all draining stuff like notifications and actualization.

turn off/on Siri was a point in the battery overview but not in drain. Wifi on/off had no effect. Hard reboot also. Then I asked my carrier for a new sim (my old one was like 6 years old) - no effect.

i tried a lot of what was written in the post.

no drain on flight mode, a high drain with LTE/5G/5G auto enabled, also a decent drain with no mobile data, only mobile Service with no data. so it’s not just mobile data Problem in my option, also Mobile communication.

then I read about the setting to chose carrier Manually or automatically. After I set it to Manuel and chose my carrier my drain was mostly gone. I guess not completely but it’s like 100 times better.

give this Option a try! It was like 4% in 6/7 hours.

to those who say „plug in power over night“: the drain is constant, all the time. But over night u can see the drain because u were not using the phone. A 4%/h means the battery is empty after one day even without using it. Even faster when using.

to those who wonder, why there is no drain for some hours when the battery is at 100%: the percent is a linearization of the batteries voltage curve. But after charging if the voltage is slightly above the linearization peak value, the percent loss is not visible.

i just wonder how people got rid of if after Serveral refunds?

i hope apple will get this issue fixes next update for everyone!

I am having the same issue with my 12 Pro, losing 3-4% battery on idle during the night. I also got it already replaced and the new one seems to have the exact same issue. So waiting 6 weeks for the replacement unit did nothing. Thank you👌

I now created an automation running every 30 minutes to log battery level in a file on iCould.

I also did some previous analysis, playing around with setting disabling everything etc, without any significant change.

Now the interesting part, I figured out that battery draining is only happing with an inserted SIM card! (Flight mode does not have any effect), only removing the SIM card from the iPhone! I also think it has to do with the modem only!

I am using Telekom (Germany), perfect signal, wifi connected. So poor signal should not even have an impact, because wifi.

I am going to switch to eSIM tomorrow, hoping to fix it with it.

Results

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19.12.20;09:00;53; noSIM

LTE + wifi: 12% in 4h idle -> 3% per hour

no SIM + wifi: 2% in 5h idle -> 0,4% per hour

Another night (not perfect without SIM, but definitly an improvement!

Hi,

I purchased the iPhone 12 Pro last week. I did not have this problem initially. Standby was great loved the phone. Then one morning I found my phone had lost 30% of battery overnight. Like below.

I contacted apple support and they were like "the battery is consumable and there is nothing wrong with it". How the **** did they even think that was a proper justification. With no help from them I set about looking into other options. I initially tried a network reset because the drain seems to be pointing to the modem. Why I say this you ask, because the standby is great in airplane mode with Wi-Fi and Bluetooth on. I assumed the issue with the 5G modem. Anyways, the network reset did not help.

With lost hopes, I finally tried to restore my iPhone using iTunes. Wola!, that kinda fixed the standby issue for me. This is the battery report from last night.

Definitely not as good as when I bought it. But will take it any day over the crap I saw a few days ago. You might ask why not perform a "Erase All Contents & Settings". Well that only clears the data on the phone and restores the settings to its default. Where as the iTunes restore strips the OS and firmware of the iPhone completely and rebuilds it from scratch. That way any major issues are generally resolved on the iPhone. Here is the article on how to perform the restore using the recovery mode.

If you can't update or restore your iPhone, iPad, or iPod touch - Apple Support

Try it and let me know if it helped. Lets hope apple comes up with a fix soon. Cheers!!

Update: Issue seems to be resolved

So after my 12 pro drained 25% during 6 hours in standby mode. I contacted Apple support who ran diagnostics. When the issue first happened my iOS version wasn’t updated as the phone was new. I updated to 14.3 and the issue seems to have been fixed

i did a test with my old XS Max, I charged both phone fully, both using a SIM with settings to LTE, WiFi on. I basically had identical settings on both phones in all aspects.

thankfully I woke up today and my 12 pro didn’t drain a single percent compared to the first night! I am so relieved but it is too early to say it won’t happen again.

I got my 12 Pro around Christmas Time, and it was most likely assembled sometime in November (I think I saw November as the manufacture date show up in the coconutbattery app on my Mac). I don't think it's a specific batch problem since I am having the issue as well. I disabled my esim today and my iPhone is sitting on 100% since like 8 hours.

Another iPhone (6s) in my house with the original 5 year old battery and still 85% battery health running the same 14.3, on the same carrier, pretty much the exact same settings enabled/disabled to minimize battery drain, dropped only 3% last night (Wi-fi, cellular, Bluetooth etc everything enabled).

Something is wrong with the cellular modem and it is not being put into standby properly if the sim is active. Disabling or removing the Sim, everything is normal. I really do hope that it's only a modem firmware related problem. Apple needs to fix this, push out a 14.3.1 with a modem update so this can come to an end. I hope they are taking it serious enough and not ignore it because as of now, we are still a minority compared to the millions other iPhone 12 users who seemingly do not encounter this issue.

This would be my second post here regarding iPhone 12 pro 256GB in USA. I have had this phone for now 10 days. Initially, I had an issue with battery draining when it is completely idle for 7-8 hours, on wifi and data off at about 7-10%. I called Apple support and escalated this issue to engineering team. The reply was my battery was behaving way above average its life. Apple support told that it takes time for a new battery to adjust itself for new ios as well as the usage and charging habit of an individual. After that it will perform to its fullest capacity.

Then for the last 4-5 days, after I got reply from Apple, I have been observing battery while idle, using on only wifi on/off and also only data on/off, and both of them on at the same time. While in idle state for 7-8 hours, with wifi and LTE data on, it hardly drops 1-2%, so that's a much improvement. Then on usage with only wifi on and only data and with both on, I used the phone and it lasted 8-9 hours straight, battery drops from 100% to 17% till this usage. This includes Facetime (on data as well as wifi), whatsapp video call and texting, Facebook, Safari surfing, speedtest app, Apple inbuilt mail app to check emails, accessing photos, playing a light (less power consuming) game, regular phone calls, and other apps like banking, paypal, weather, news, and playing with settings and also just surfing the screen here and there. I didn't take any photos or videos in these 8-9 hours of usage.

I have regular postpaid sim card.

So I think you should allow your new iPhone to settle down a bit and get used to the new environment.

Few suggestions I found so far.

1. Apple told to charge the battery to 100% all the time. Heat also effects the battery life, so try to avoid using phone while charging and also avoid direct sunlight (it is likely to drain more in idle state in hot environment).
2. I also reduced the "white point" to 50% which is in settings --> accessibility --> display & text size all the way option. I didn't put on lower power mode until it switches automatically at 20%. Brightness during this usage was from 15% to 90%, most of the time it was 25%) as I was indoor.
3. Also turn on "dark mode" on whenever possible, especially at night. It will help white pixels OLED screen consume less power.
4. Other settings, I always keep privacy --> location services to never or while using app option for all the apps. Also turn off location for all the system services except Emergency calls & SOS and Find My iPhone. Also turn off Signification Locations under system services.
5. Background refresh is turn off completely.
6. Notifications are on for certain apps only otherwise off.
7. Turn off the push option for emails. Rather go for manual fetch for the all the emails you got or if you need push option then go for hourly fetching.
8. Avoid automatic icloud backup.
9. Avoid automatic updates of app.

I have had used iPhone 6 and 7 since 2015 and had these consistent settings on all my iPhones. This helped a lot.

Note: Apple should now concentrate more on performance rather than just design and display. It's 2021, we are on the electronic gadgets most of the time. Battery is going to be the main concern for all gadgets like gaming, laptops, phones, or even in that case electric cars Apple should change their conservative approach to more liberal Otherwise, competitors will be ahead in the race in coming years. I hope Apple don't lose its charm.

Hope this will help you all here.

This would be my second post here regarding iPhone 12 pro 256GB in USA. I have had this phone for now 10 days. Initially, I had an issue with battery draining when it is completely idle for 7-8 hours, on wifi and data off at about 7-10%. I called Apple support and escalated this issue to engineering team. The reply was my battery was behaving way above average its life. Apple support told that it takes time for a new battery to adjust itself for new ios as well as the usage and charging habit of an individual. After that it will perform to its fullest capacity.

Then for the last 4-5 days, after I got reply from Apple, I have been observing battery while idle, using on only wifi on/off and also only data on/off, and both of them on at the same time. While in idle state for 7-8 hours, with wifi and LTE data on, it hardly drops 1-2%, so that's a much improvement. Then on usage with only wifi on and only data and with both on, I used the phone and it lasted 8-9 hours straight, battery drops from 100% to 17% till this usage. This includes Facetime (on data as well as wifi), whatsapp video call and texting, Facebook, Safari surfing, speedtest app, Apple inbuilt mail app to check emails, accessing photos, playing a light (less power consuming) game, regular phone calls, and other apps like banking, paypal, weather, news, and playing with settings and also just surfing the screen here and there. I didn't take any photos or videos in these 8-9 hours of usage.

I have regular postpaid sim card.

So I think you should allow your new iPhone to settle down a bit and get used to the new environment.

Few suggestions I found so far.

1. Apple told to charge the battery to 100% all the time. Heat also effects the battery life, so try to avoid using phone while charging and also avoid direct sunlight (it is likely to drain more in idle state in hot environment).
2. I also reduced the "white point" to 50% which is in settings --> accessibility --> display & text size all the way option. I didn't put on lower power mode until it switches automatically at 20%. Brightness during this usage was from 15% to 90%, most of the time it was 25%) as I was indoor.
3. Also turn on "dark mode" on whenever possible, especially at night. It will help white pixels OLED screen consume less power.
4. Other settings, I always keep privacy --> location services to never or while using app option for all the apps. Also turn off location for all the system services except Emergency calls & SOS and Find My iPhone. Also turn off Signification Locations under system services.
5. Background refresh is turn off completely.
6. Notifications are on for certain apps only otherwise off.
7. Turn off the push option for emails. Rather go for manual fetch for the all the emails you got or if you need push option then go for hourly fetching.
8. Avoid automatic icloud backup.
9. Avoid automatic updates of app.

I have had used iPhone 6 and 7 since 2015 and had these consistent settings on all my iPhones. This helped a lot.

Note: Apple should now concentrate more on performance rather than just design and display. It's 2021, we are on the electronic gadgets most of the time. Battery is going to be the main concern for all gadgets like gaming, laptops, phones, or even in that case electric cars Apple should change their conservative approach to more liberal Otherwise, competitors will be ahead in the race in coming years. I hope Apple don't lose its charm.

Hope this will help you all here.

SOLUTION —PROB. FIXED

hello all I was reading about the problem a lot and I was having the same battery drain issue in 6-8 hours with lots of heating, and I did fix it and now the battery is staying for 2 days with heavy usage. HERE IS HOW TO FIX IT:

1- Go to settings >> Cellular

2- Select Cellular data options

3- Voice & Data

4- Select 5G Auto

Done ✅

see the attached photo and read what 5G On do to your battery life and it is the default selection I guess, so you need to change it and enjoy your full baterry life..

hope That this fixes your problem.

have a great day.

Hi all

MY SOLUTION -> SETTINGS -> MOBILE DATA -> NETWORK SELECTION -> TURN OFF AUTOMATIC NETWORK SELECTION -> CHOSE THE SAME CARRIER THAT WAS AUTOMATICALLY SELECTED BEFORE

Context:

I am from Central Europe and I have an iPhone 12 with ios 14.3 (European version without mmwave 5g).

My carrier is Telenor and in my country they don't have 5g. In the settings, I only can choose from 4g or 3g.

I’ve been trying to find the source of the problem for months. I think its an iOS bug which is good because easier to solve them.

I tried many tips from this forum, but most of them are basic tips to improve battery life which is good but not the solution for the problem. I have isolated most of the settings from the problem, I think its not a wifi, Bluetooth or mobile data network issue. For some people changing carrier was the solution that was interesting because carriers not affect battery life. The solution for me was turning off automatic network (carrier) selection. I turn off automatic network selection and then select the same carrier that I used before. That's it, finally I have better battery life than a used iP7 with 80% battery health.

This would be my second post here regarding iPhone 12 pro 256GB in USA. I have had this phone for now 10 days. Initially, I had an issue with battery draining when it is completely idle for 7-8 hours, on wifi and data off at about 7-10%. I called Apple support and escalated this issue to engineering team. The reply was my battery was behaving way above average its life. Apple support told that it takes time for a new battery to adjust itself for new ios as well as the usage and charging habit of an individual. After that it will perform to its fullest capacity.

Then for the last 4-5 days, after I got reply from Apple, I have been observing battery while idle, using on only wifi on/off and also only data on/off, and both of them on at the same time. While in idle state for 7-8 hours, with wifi and LTE data on, it hardly drops 1-2%, so that's a much improvement. Then on usage with only wifi on and only data and with both on, I used the phone and it lasted 8-9 hours straight, battery drops from 100% to 17% till this usage. This includes Facetime (on data as well as wifi), whatsapp video call and texting, Facebook, Safari surfing, speedtest app, Apple inbuilt mail app to check emails, accessing photos, playing a light (less power consuming) game, regular phone calls, and other apps like banking, paypal, weather, news, and playing with settings and also just surfing the screen here and there. I didn't take any photos or videos in these 8-9 hours of usage.

I have regular postpaid sim card.

So I think you should allow your new iPhone to settle down a bit and get used to the new environment.

Few suggestions I found so far.

1. Apple told to charge the battery to 100% all the time. Heat also effects the battery life, so try to avoid using phone while charging and also avoid direct sunlight (it is likely to drain more in idle state in hot environment).
2. I also reduced the "white point" to 50% which is in settings --> accessibility --> display & text size all the way option. I didn't put on lower power mode until it switches automatically at 20%. Brightness during this usage was from 15% to 90%, most of the time it was 25%) as I was indoor.
3. Also turn on "dark mode" on whenever possible, especially at night. It will help white pixels OLED screen consume less power.
4. Other settings, I always keep privacy --> location services to never or while using app option for all the apps. Also turn off location for all the system services except Emergency calls & SOS and Find My iPhone. Also turn off Signification Locations under system services.
5. Background refresh is turn off completely.
6. Notifications are on for certain apps only otherwise off.
7. Turn off the push option for emails. Rather go for manual fetch for the all the emails you got or if you need push option then go for hourly fetching.
8. Avoid automatic icloud backup.
9. Avoid automatic updates of app.

I have had used iPhone 6 and 7 since 2015 and had these consistent settings on all my iPhones. This helped a lot.

Note: Apple should now concentrate more on performance rather than just design and display. It's 2021, we are on the electronic gadgets most of the time. Battery is going to be the main concern for all gadgets like gaming, laptops, phones, or even in that case electric cars Apple should change their conservative approach to more liberal Otherwise, competitors will be ahead in the race in coming years. I hope Apple don't lose its charm.

Hope this will help you all here.

Less

*Something I posted to another thread a week ago.

For everybody who would feel disconnected if they'd enabled airplane mode

While I am at home, I have airplane mode enabled all the time now (Wi-Fi is on constantly, Bluetooth only occasionally) and I have received every call and every text and am not compromised in any way. Please read.

A couple days ago I realized, even if airplane mode is on but Wi-Fi including Wi-Fi calling enabled, I can make/receive calls, send and receive non-imessage texts just normally. This is game changing. If this means I can just use my phone in airplane mode every time I am connected to Wi-Fi someplace, this is going to greatly improve battery life in every way. Because it means that the usual battery drain while having bad 1 bar cell reception in a certain spot in a building suddenly is eliminated. Granted there has to be Wi-Fi.

Here's a screenshot. Last charge to 100% was Saturday 8:30AM. Now it's Sunday midday and I am on 88%. I admit I don't have all too much screen-on time since yesterday however it was quite a lot of standby time. Considering that before, the phone would drain to 88% at the very least just sitting there idling over the course of 8 hours. No matter day or night. (I am saying 'no matter day or night' for all the people who insist everyone should charge their devices over night every night. Because the phone would drain on its own during the day just doing nothing as well.)

Also a thing I notice (especially on my iPad Pro) but that could just be placebo or something like that. If you drain your device to ~40/50% and then charge it back up, it usually has less standby drain and overall lasts a little bit longer as opposed to already charging it back up when it's only on 80%.

Also, I don't like Significant locations being turned on, which on the one hand bricks optimized battery charging for me but since I don't really have a steady charging/usage routine it would mostly likely not engage for me anyways, therefore it isn't a big deal because I plug in my phone when it drained around halfway or sometimes a little sooner, charge it, leave it plugged in sitting on one hundred percent for one hour max. If you unplug right when it reaches 100% it will mostly likely not sit on 100% for very long. (Apple devices are not fully charged by the time they display 100%. Depending on the device, charging it for an additional hour will make certain that the battery is in fact fully charged)

I am in no rush anymore because I am quite happy with the "workaround" as for now and this might be just the way I go from now on regardless of wether they fix the issue or not. Because I get better battery life that with every iPhone I had so far combined. And it's not too big a headache once you have simply integrated this procedure into daily life. (Granted, you need to have a contract that enables Wi-Fi calling for you to actually be able to utilize this). Turning on airplane mode when you get home and disabling it as soon as you disconnect from Wi-Fi (just like you maybe would go into Control Center to disable Wi-Fi when you head on out or disable Bluetooth when not needed anymore anyways), and all in all my battery lasts 4 days with ease doing it this way and like I said, its barely an inconvenience. I also got great battery life and no abnormal drain while on cellular data recently but you'll need to be in an area with great reception. (Recently, connected to LTE with 4 bars [I don't have 5G but I am on 5G Auto regardless, my phone sometimes manages to switch to 3G that way, it doesn't if I only select LTE], 20min of listening music streamed over Apple Music via Bluetooth in the car, 30min listening to music (wired headphones), some other minor things and in 2 hours I had lost exactly 1%!) I guess the issue is mainly there if the reception isn't 100% solid and the modem for some reason needs an awful amount of power, which most certainly seems like a software bug and that could be related to the carrier and how often a cell tower checks with your phone or how often the modem is set to update itself. Or maybe some carriers check more often than others, I don't know. Just speculation here!

[Edited by Moderator]

Diana, both self and wife bought new iphone 12 pro in December. ( replaced old iphone 6 after 5.5 years) IOS14.2 as delivered and updated to IOS14.3 both phones had battery drain up to 25% overnight unless flight mode used. Both on O2. Updated both to IOS14.4, both fixed, overnight battery drain around 3% which is acceptable

hope 14.4 fixes it for you.

You do only have one bar of cellular connection though. Doesn't even matter if you're on Wi-Fi and have Cellular Data disabled. As the cell modem is still going to be active. Unless you have Airplane Mode enabled or no SIM installed, your device is always checking for a cellular network even though you are browsing the web via Wi-Fi. You might benefit from enabling Wi-Fi calling if you're carrier and contract supports it, as it connects to your cell network via Wi-Fi and greatly decreases power consumption when you're indoors and the reception is somewhat bad.