iPhone 12 losing service

I have the same issue with LTE on iPhone12, switching LTE to 3G and back (Mobile Data>MobileDataOptions>Voice&Data>) helps to refresh the connection. But that definitely not the best solution @apple, so I returned that device and got a refund.

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

Same problem here with brand new iPhone 12 Pro Max, i constantly lose service while driving in car or train. after about 500m - 1000m it drops my call and i have to call back again (which is possible immediately after the call drops). Seems there is a problem with changing the mobile cellular radio cells.

Tried SIM cards from Vodafone and O2, the problem occurs on both.

When I put my Vodafone SIM card into my previous iPhone 11 Pro Max, no dropping calls at all, everything works fine.

Tried any way of configuration and a complete reset o iPhone 12 Pro Max. Nothing helped.

So: This is definitely a iPhone 12 (Pro) Issue, maybe 5G Modem /-Baseband related. I remember similar issues when the new Galaxy S20 Ultra released.

After a call with Apple Support they told me, that they haven't heard about this before (hard to believe, while all big Apple-Mags and forums have articles and threads about that issue). As there is no entry in the support database for this issue, i (and the support guy) don't think there is a quick fix around the corner. So my device will be returned to Apple for refund.

It's not Apple's error.

The MTSOs are telling the iPhones to use a channel that isn't working well and are being obstinate about forcing them to use that channel regardless.

Apple's phones can only use the frequencies they are told to by the cell tower, they can't just jump to a frequency that would work better.

The same is true with the issue with QoS and Wi-Fi calling; it's not an Apple issue per se, it's poorly implemented QoS in those Wi-Fi routers.

The thing about playing with networking standards is everyone has to agree to follow the rules, or problems like this will happen.

With the release of each new iPhone, problems inevitably crop up and those issues are not resolved by future iOS updates, they are resolved by future carrier updates.

Why? Because many cellular carriers adopt a standard of "Hey, it works with this phone, it should work with all of them" which is not how the appropriate standards say things should work.

Apple has a "no questions asked" return policy of 14 days, however they will easily accept a return within 30 days of date of order. Also, if you've got an open support case with them, they can make an exception and will accept a return beyond 30 days. Call support, give them your case number and ask for level 2 support, and then ask them to initiate the return process. Be polite and assertive if you're asking for an exception to their published return policy.

I can confirm that both Apple and Verizon (at least at the level 2 support teams and engineering teams) are aware that some phones aren't working properly and they are working to address the issues. Front line support folks seem to still be in the dark, however.

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.

https://www.google.com/amp/s/www.forbes.com/sites/gordonkelly/2020/12/01/apple-iphone-12-pro-max-iphone-12-mini-4g-5g-cellular-signal-problems-iphone-11-pro-max-upgrade/amp/

This was posted by Forbes on the 1st of December 2020. I get your point and completely respect it. Again, I mentioned the issue on an Apple forum because I am aware Apple Pay’s attention to these and perhaps they’re unaware of the issue and can fix it in a coming update.

The more you research this issue, you will find many more articles, forums, etc. Where many many people are sharing having the same issue. Again, in my experience, every single iPhone 12 I have handled has given me this issue, some more severe than others and I will stand by this claim.

I’m not here to argue with anyone but instead to address an issue that I along with many others are also having.

Sillydg wrote:

Apple contacted Verizon and they reconfigured local towers to connect on the right signal bands. Before the config change, the phones were connecting on weak-signal bands.

Proving it is a carrier issue.

I have solved the problem with my phone and will be unsubscribing from this group. Thanks to all the me too comments, and knowing mine was not an isolated case, I returned my iPhone 12 and purchased an iPhone 11. No cellular issues or dropped calls. Problem

solved. If you purchase as 12 KNOW the return policy from your store and use it if needed.

If it were a hardware issue alone it would affect everyone, but it does not.

It's most likely to be an interaction between the hardware and a certain revision of software at the cell tower or a certain brand of cell tower software/hardware.

To bring this full circle, I recommend everyone who has this problem to bring it up to both your carrier and to Apple support directly.

Contact - Official Apple Support

justlaur wrote:

Since Monday (it’s now Thursday), my husband’s phone (which was mine last

week) drops to no SIM and no service many times a day while we’re both at home on the same couch and mine (which was his last week) has functioned perfectly.

The bad news is that whether it’s a software issue, hardware issue, firmware issue, 5G issue or carrier issue - it’s affecting many people in many countries on many carriers and still hasn’t been fixed. It’s not my job to keep troubleshooting the issue for them. Apple and the iPhone 12 devices themselves are literally the only constants in this thread. Many carriers, many towers, many bands, many locations, many people, but only one type of phone made by one company. I’m counting on the company representing the one common element to provide the fix, regardless of whose fault it is.

There is no doubt whatsoever that a No SIM alert indicates a hardware problem. Whether that is a bad SIM or a fault in the iPhone can only be confirmed if you test by substitution (swap the SIMs between phones), which you hint at but don’t say explicitly. If the fault stays with the same iPhone when the SIM is swapped for a known good one the fault is in the iPhone, and it should be replaced under Apple’s warranty provisions.

The simple fact you identified the problems as involving many networks, towers bands, locations suggests there are still too many unknowns in play to determine a cause. The reported problems here represent a tiny percentage of iPhone 12 (whatever version) users, most without problems. If there was a defect in the phone (or software) I would expect it to hit many more users, like a whole batch of production likely to be hundreds of thousands. I think it is more likely there are multiple problems which happen to look the same from a user perspective although they have different technical causes. Unfortunately this makes fault finding extremely difficult because the users all maintain it is the same fault (what they can see) rather than raising individual support cases with their network and/or phone supplier, for individual fault finding.

I tried something just out of sheer curiosity and I'm relived yet irritated.

My Verizon device has to operate off of a signal booster in my home otherwise It would be a $1000 paperweight. After talking to Verizon Tech level 2 and inquiring about returning the device and disconnecting services, I decided to ask about having a replacement phone mailed to me as a last ditch effort. I previously made this request however as it was so close to launch day they didn't have the inventory.

Fast forward 2 days later to today I received the replacement device only to have the same issues as the 1st phone. Being that all of this was going on I decided to leave my T-Mobile phone activated and im glad that I did. I had a random thought to place the T-Mobile sim from my iPhone 11 into the Verizon 12 Pro Max and figured that the replacement device was locked to Verizon. It wasn't.... As soon as my T-Mobile sim registered in the iPhone 12 the speedtest app that was struggling to download on both Verizon 5G and LTE for 5 or so minutes finished downloading instantly on 2 bars of T-Mobile LTE.

Needless to say Verizon can have all off their stuff back. 

I pondered keeping the replacement device and just paying it off with Verizon but I much rather deal with T-Mobile If I need to resolve any matters. From the looks of it Verizon is grossly unprepared as a carrier and I believe their service on the devices should have been vetted properly before the keynote.

Update on my experiment to make my phone work:

I switched to 4 G LTE on my iPhone Pro 12 (cellular network Verizon). It ran better today, a little slower and glitchy but totally decent. It reminded me of how a typical smart phone runs with modest interference. I had my navigation, listened cable TV broadcast app and switched between phone calls (hands free) while driving 45 minutes away from home and back.

Basically, I will keep my iPhone 12 Pro and switch to 4 G (which is a little disappointing) until the Verizon network (and other effected companies) and Apple get things straightened out for true 5 G availability and phone compatibility on ALL networks.

Some phone companies are doing better than what I have—Verizon, but I have to pay this iPhone phone off, so hopefully Apple will give an update so these phones can toggle better. Until then...

I’m convinced that Verizon is a common denominator based on other forums as well. Verizon sent me a signal booster which increased my service but then I realized that essentially I was just using my WiFi being that it had to be hard wired into my router so I unplugged the booster.

I have since began the process of switching over to T-Mobile and decided to randomly do a speed test and was shocked at the results. I’ve only seen 10 mbps in my home at 5 AM a few times and throughout the day it’s usually 1-2 mbps w/o the booster. Today I ran a Speedtest and 40 mbps showed up. It took close to 2 months for signal to be “corrected”.

Verizon has way too many kinks to work out for me to continue service with them.