iPhone 12 losing service

“....This has nothing to do with an app installed on the phone.....”

• Yes, I just said that to Dominic1243. I never claimed it had.

“...Since when can you run antivirus on iOS?!...”

• OK my bad collective noun, should have said there is no place for mobile security apps on iphone, even though many claim also to be antivirus.

”...VPN definitely has a place on a device.....”

• your choice but choose wisely

https://www.forbes.com/sites/simonchandler/2019/09/23/too-many-vpns-put-our-privacy-and-security-at-risk/

and be polite if you come back, but this is off topic.

I just found something that might give a clue as to where this is coming from.

The problem that the cell connection drops seems to be connected to location services. In particular the "precise location" option.

If you have this problem, try the following and see if it makes a difference:

• First, turn off all your location services (Settings - Privacy - Location Services). Try that for a while in the same places that you had intermittent connectivity issues before.
• Second, turn on your location services again but make sure to leave the "Precise Location" option off.
• Third, see if it makes a difference on 4G and 5G Auto/On.

Here is my experience:

After I had turned all location services off, the problem went away. I turned the location for the Apple Maps app back on, but left the "Precise Location" option off. When I was using the Apple Maps app and I selected "Precise Location: Allow Once", the cell connection immediately dropped, very reliably too. This issue happened on 4G/LTE but not on actual 5G in my experience (though actually it's hard to tell when it's on 5G Auto).

So what does this mean? Is there a problem with the antennas in conjunction with GPS? Is it a hardware problem or can Apple fix it via update? So many questions.

Actually, it may be.

When you compare the specs of the iPhone XR with the 12 Pro Max, for US phones you see this:

iPhone XR:

• FDD‑LTE (Bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 17, 18, 19, 20, 25, 26, 29, 30, 32, 66, 71) 
• TD‑LTE (Bands 34, 38, 39, 40, 41) 
• CDMA EV-DO Rev. A (800, 1900 MHz)
• UMTS/HSPA+/DC-HSDPA (850, 900, 1700/2100, 1900, 2100 MHz) 
• GSM/EDGE (850, 900, 1800, 1900 MHz)

iPhone 12 Pro Max:

• 5G NR (Bands n1, n2, n3, n5, n7, n8, n12, n20, n25, n28, n38, n40, n41, n66, n71, n77, n78, n79)
• 5G NR mmWave (Bands n260, n261)
• FDD-LTE (Bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 17, 18, 19, 20, 25, 26, 28, 29, 30, 32, 66, 71)
• TD-LTE (Bands 34, 38, 39, 40, 41, 42, 46, 48)
• CDMA EV-DO Rev. A (800, 1900 MHz)
• UMTS/HSPA+/DC-HSDPA (850, 900, 1700/2100, 1900, 2100 MHz)
• GSM/EDGE (850, 900, 1800, 1900 MHz)

So, if you shut off 5G, the phone will revert to LTE.

The thing to notice is the difference in the TD-LTE bands; the 12 Pro Max supports bands 42, 46 and 48 where the XR did not.

So, your cell phone comes along and the equipment at the MTSO says "Cool, you're an iPhone 12 Pro Max, use band 46."

But, the tower is having issues with band 46, for whatever reason.

The MTSO knows an XR doesn't support that band so tells an XR to use band 40.

The XR sees full signal on band 40 and you can happily use it all day long.

The 12 Pro Max sees no signal on band 46 and reports "No signal."

Is this what's happening? Only your carrier knows, but this is but one way this can happen.

Not for nothing, but we also saw this happen when the iPhone 11 family was released because it too could support bands the previous generation of iPhones could not.

The way this typically gets fixed is via a Carrier Update from the cellular carrier and/or they fix their cell tower.

I have the No Signal problem on my 12 Pro on Verizon. I was testing app downloads over cellular because it seems to show the problem.

While doing this I noticed that I could get service back by texting to my Verizon escalation number. This is a green bubble non-iMessage number (899000). The text will fail, then service comes back, then you can retry the text.

Does a green bubble text restore service for anyone else?

Test Steps

• Turn off WiFi in Settings
• Download VainGlory app, it’s large
• if service is lost, text to green bubble number
• if download succeeds, then run app, then delete app and repeat test

The iPhone 12 can access the following LTE frequency bands:

• FDD‑LTE (Bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 17, 18, 19, 20, 25, 26, 28, 29, 30, 32, 66, 71)
• TD‑LTE (Bands 34, 38, 39, 40, 41, 42, 46, 48)

The iPhone 11 can access these:

• FDD‑LTE (Bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 17, 18, 19, 20, 25, 26, 29, 30, 66, 71)
• TD‑LTE (Bands 34, 38, 39, 40, 41, 42, 46, 48)

Thus if a cell tower's BSC assigns the iPhone to use a FDD-LTE frequency in bands 28 or 32, it may fail if there are tower or equipment issues that would never be seen on an iPhone 11 because the iPhone 11 doesn't support those frequencies and would tell the BSC that.

Just wanted to provide my experience, in case it may be of any help to others.

• purchased 12pro/Verizon/128g
• immediately encountered same issue as described in the threads (phone randomly looses service and does not automatically ‘reconnect’ to service. Only fix to re-establish service was to toggle airplane mode on/off.
• Had multiple chats with Verizon and Apple, and agreed to try a few solutions.
• 1st, went to Verizon store, who provided new SIM card. Problem persisted after installation.
• Went to apple, who ran diagnostics and factory reset phone. Problem persisted.
• went to apple again, who provided a brand new phone. Unfortunately, problem persists on phone #2.
• The issue is remarkable (to me) because my old iPhones worked just fine in the same exact spots. Furthermore, I’ll be in the same room as my wife (who has an 11) and I loose service, while hers is completely fine. Similar story with my brother, who has the X (same room, mine looses service while his is fine).
• From my personal observation, I’m concluding this is likely an IPhone 12 specific issue, not a Verizon issue. Hopefully, a fix is on the way because I can’t keep monitoring my phone to see if I need to toggle airplane mode on/off!

Lastly, I will say that Apple has provided great customer service, and I have faith this issue will be resolved, as enough people have encountered a similar issue.

My iPhone 12 Pro Max on Verizon (Orlando, Florida) had connectivity issues, dropped and failed calls. Spoke with Verizon support earlier today and they were able to help me resolve the issue:

• Settings
• Cellular
• Cellular data options
• Voice & Data - select > LTE

5G is very weak in Orlando and my iPhone used to disconnect because it was on > 5G AUTO (it was trying to connect to 5G network which was almost absent and then trying to switch back to LTE). If 5G is bad in your area, there is no point to try connecting to it. Just use LTE network only and you should have no issues with dropped calls (I hope it helps).

I think I figured out how to fix my intermittent no signal/no sim iPhone 12 Pro on Verizon issue. TLDR: Erase iPhone and Setup as New. 

I was a long time AT&T customer who just switched to Verizon since I can see a Verizon 5Guwb cell site outside my window, plus there was nice trade-in value for my iPhone XS. 

Last week I convinced Apple to send me a replacement iPhone 12 Pro to help fix my no signal /no sim issue. I backed up my first iPhone 12 Pro, then had to update the new iPhone to 14.3, so I could restore the backup image on to the second 12 Pro. Using my original Verizon 5G sim, the new iPhone worked well for about five hours and then I started to see the no signal/no sim issue on the new phone. Bummer. 

Since I had two identical blue iPhone 12 Pro 512GB models, I decided to run a test on my first iPhone 12 Pro. I used iTunes to restore a clean copy of 14.3 on my first iPhone, inserted the Verizon 5G sim and manually setup the iPhone without using the backup image. 

Normally I could repro the no signal issue pretty much at will by turning off the phone and then turning it on again and watch it struggle to lock in on a cell signal, or by installing/uninstalling apps and seeing the signal start searching after the install/uninstall. 

With the first 12 Pro, now setup as new and on cellular only, the signal was solid when I turned the phone on and when installing/uninstalling apps. So far so good. 

To test overnight, I kept WiFi off and streamed a Twitch stream all night over cellular. When I woke up the stream was still going. Great. 

Since I had a replacement phone from Apple, my AppleCare switched automatically from the first 12 Pro to the second 12 Pro. So I need to setup as new on the second 12 Pro. So I proceeded to do the following:

1. Backup 2nd 12 Pro
2. Restore new backup on 1st 12 Pro, so we can view settings and apps when setting up 2nd 12 Pro from new. 
3. Erase 2nd 12 Pro
4. Insert Verizon 5G sim in 2nd 12 Pro and setup phone as new. I kept WiFi off during this step and the following steps to test out the cellular connection. 
5. Change settings and install apps as needed. 

So it’s been 24 hours since I setup my 2nd 12 Pro as new and I haven’t seen the no signal/no sim issue so far. I’ve been on cellular only most of the time. 

Apple can probably fix this in a future release. There’s some setting that gets transferred during the backup/restore process, that makes the no signal/no sim issue pop-up, that the following processes don’t clear as of 14.3.

1. Reset Network Settings
2. Reset All Settings 
3. Backup iPhone, Erase All Content and Settings, Restore from Backup

I previously tried the above three work-arounds and none of them worked.  But the following did work for me. YMMV

1. Erase All Content and Settings
2. Setup iPhone as new

I know it’s a PITA to setup as new, but it’s better than dealing with the no signal issue. 

i'm having the same problem with my iphone 12 on t-mobile.

• cell signal would drop to one bar and sometimes no bars in places where my old iphone 8 plus had full bars (namely in my home).
• people are saying calls go straight to voicemail when they call me
• i would notice voicemails when my phone never rang
• sometimes when my phone loses all signal, it would never come back and the only way for me to regain signal is to restart they phone (toggling airplane mode doesn't work).

hoping apple fixes these problems soon

Hello,

This is what mine shows.

Though it looks like this may only apply to businesses (which is how I bought mine). Kinda interesting. I’m going to verify with my Apple rep because the link you provided doesn’t show a restocking fee.

Sorry in advance for the long think piece. Here's my experience with Verizon as a new customer that ordered a iPhone 12 Pro Max.

I'm having data issues in Jacksonville, Fl. I just switched to Verizon on the Pro Max launch day and was shocked when I did a speed test and it came back with 3 MBPS on 4 bars of 5G. Me understanding that 5G speeds without ultra Wideband is somewhat of a gimmick I decided to toggle the phone to LTE only and actually got slower speeds than the 3 MBPS. I drove around my neighborhood and there was no change. Drove around my side of town and got decent speeds 15-20 MBPS within a 3 minute drive of my house. Called Verizon and spoke to a rep (I'll save the story for how bad the customer service is for another time) he said that he could put through an order for me to get a free signal booster....call dropped on my T-Mobile phone that I switched from before he was able to put through the order. Before the call was disconnected we did every troubleshooting step imaginable. I not only did a reset on my network settings but the entire phone numerous times. I Called back and waited for an hour but Tech 2 wasn't answering so I decided to go to the Verizon store and get a SIM card switch because I thought it may have just been faulty.

As I pull into the Verizon parking lot my speeds were booming over 50 MBPS the store rep said to disregard it because the store has signal boosters and its not a true reflection. He was very much so correct. He was hesitant to swap out my SIM card but I insisted because I need any solution possible to fix this train wreck. Before I leave the store he tries to sell me the same signal booster that I was offered for free for $300 😒. As I leave the store I have the same issue so I called back into tech support and now I'm being told that a ticket has to be put in before I can be approved for a signal booster. He puts in the ticket and states that by 11/17 I should get an answer. On 11/18 I called tech support again just to realize that the ticket was never put in and I'm having to start all over again. The new Tech 2 rep was great and thorough but said somethings that made me raise my eyebrow. According to him my phone is fine and doesn't need to be replaced but he mentioned that it looked as though I was being throttled like I went over 50 GB and was in a congested area. With me having the phone for less than a week and barely able to load a YouTube video that's impossible. He remote accessed my phone and literally watched as I did a speed test and was floored at the 1 MBPS speed on both 5G and LTE. He placed another ticket and stated that they'll reach out within 48-72 hours with a resolution hopefully. I grew anxious last night and did a chat with Verizon support through Twitter and was told that my house was literally in the middle of two towers and that I should have any issues according to the coverage map. The lies from the coverage map is what made me leave T-Mobile....tbh even with all that's going on I still wouldn't go back to them right now.

On 11/19 I noticed that in my settings it looked like I had a digital sim activated which is what I thought would be causing issues. Called tech support again and was told that everything is normal in their system. The tech checked on my ticket advised me that it was still open which was a good thing but also saw that there was a memo placed out on all iPhone 12 models. She stated that from what she could see it was related to data access and 5G availability and that they made Apple aware of the issues going on. She even cracked a joke that Verizon's infrastructure wasn't ready for all of the 5G phones being added to its network. At this point it's a waiting game....Call quality for me has been amazing in comparison to T-Mobile and the dropped calls that Ive had since April.

I locked my phone to LTE only and that was a short temporary fix. I called Apple support and the rep of course stated there there's no known issues and that this matter should be taken up with my carrier. He was able to secure me a Genius Bar appointment however that would take me out of the 14 day return window.

This is also happening to my new iPhone 12.

I received the phone direct from Apple and have T-Mobile and live on Long Island NY

it has happened 3 times that o have seen in the last week.

the phone goes to 1 bar and LTE flashes on and off and I can’t make phone calls or use data. The only fix is to wait it out ( usually fixes itself after about 10mins ) or to turn off my phone and back on.

spoke to Apple and was escalated to senior advisors that ran a diagnostic log on my phone and sent to the engineers.

waiting to hear back but I honestly think this will be a while

until it’s fixed.

if it’s software that would be easy for them but if the phones themselves need to be replaced that will take a while.

my gf also got a new iPhone 12 and hers did it the other day. So it’s def widespread.

I also have LTE on and she has 5G on.

I have tried everything as well. Still persists

****UPDATE****

After extensive testing and trying to figure out what’s going on with my phone,

When my phone looses network connection I realized that the SIM card ID is either missing completely or says NO SIM !!

Goto: Settings>General>About and scroll down to Primary.

listen under primary should be network information. Here you will see normally ICCID this is your SimCard number.

when my phone looses the connection it shows either NO SIM or Nothing at all.

this leads me to a SIM card problem or a problem with the SIM card socket inside the phone.

please check this next time your phone looses connection to see if your phone shows the same thing when it looses connection and if it shows a ICCID when working normally!

This may be a start to resolving these issues.

Thanks

You are correct that when service is dropped it shows "No SIM" - however it's not the SIM card or the slot as the same issue persists with eSIM only. The attached image is with both the physical SIM Card and the eSIM activated. Makes no difference.

Guys, there are good news, today I checked my iPhone and I found a new profile automatically installed called "Baseband and Telephony logging" installed on my phone, this means Apple is feeling and admitting there's an issue there.

Hope they can fix it soon 🙏🏼

BTW, I'm super sure I didn't installed this profile myself.