iPhone 12 losing service

Just spoke to VZW engineer, said about another 30 days. Apple pushed updates in the 14.3 and 14.4 updates, however, things needed done at every tower in order to support the handoff from tower to tower. It is not backwards compatible to pickup a 3g signal it’s is only LTE and up. So when it cannot find the lte signal it doesn’t pickup the 3g.

I turned off 5G and just left on lte, data mode turned to standard, turned WiFi assist off. Restarted the phone, went every where I dropped calls and phone deactivated. No issues today. Engineer I spoke to said give it 30 days and should be resolved in the towers.

So many people reporting issues, and so much confusion about what's causing them. I live in Portland, OR, and I purchased two new iPhone 12's when they were first released. At home I had a weak signal that would drop calls, and I constantly had to toggle in and out of airplane mode to reconnect to Verizon. After many calls to Apple and Verizon, I finally sent an email to CEO Tim Cook. That was on a Friday. On Monday I got a call from a senior engineer who reviewed my logs. On Tuesday he called back to say they were flying an engineer up from Palo Alto. He arrived at my house at 5 pm that day, and took out 5 phones to run tests on my Verizon signal. He said that he believed that the Verizon towers were not configured correctly to choose the right signal band and the Apple engineers would contact Verizon to resolve the problem. On Wednesday afternoon I suddenly had two-three bars of signal strength, and I have not had a problem since.

hi

same here.

i fixed mine. i got an apple genius bar appointment.

they refused to replace the phone but they replaced some hardware (a port maybe?) in the back for free (its covered with every new phone). it works now.

I think we found a solution. Backup -> Restore iPhone (using Mac OS) -> Restore Backup. This reinstalls the firmware which is evidently the problem.

Same issue here, i contacted Verizon tech support, they told me the 5G sim's that came with the pre orders from Apple are defective not allowing 5G service. I have ordered a new SIM and it should be here today. I will update this once i install it. Best of luck on this issue because it is annoying to have a brand new phone, with no service.....

I have the exact same issue with the iPhone 12 pro Max dropping service at certain places. The easiest way to fix it is to toggle airplane mode on and off. Obviously not an acceptable fix for an $1100 phone. Also requires that you check your phone to make sure it hasn’t dropped service if you are expecting a call or text.

I took my phone in the Apple store (11/24/20), they ran a diagnostic (found nothing wrong), reset my network settings, and gave me a new Verizon (my carrier SIM card). The person I spoke to there said others have reported the issue, so Apple is definitely aware of it and for me to contact Verizon about the issue.

I talked to a Verizon tech today (11/27/2020) that said they are aware of the issue for over a month and are sending reports to Apple about it. They recommended not switching to the SIM card provided by Apple as that won’t help. They do not have a fix for it other than to toggle airplane mode on and off, or turn your phone off and on. They are sending my info to Apple to along with others.

The best option right now is for anyone with this issue to report it to Apple and your cell carrier (Verizon or other). That way they hopefully find a fix if enough people formally report it, and someone company admits there is a problem with the iPhone 12s. Currently no one will officially admit this is a real problem with the iPhone 12s.

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.

Same issue here. Solution (as sad as it may be on the iPhone flagship) is to turn off 5G all together!!

My personal opinion is that it’s not an issue with the iPhone but an issue with Verizon’s 5G network. A friend described it best, the phone is doing something similar to when it is trying to switch between a poor LTE signal and a decent 3G signal. So far all speed tests on Verizon 5G have resulted in a significantly slower speed than LTE. Again, turn off 5G, unlike AT&T Verizon doesn’t distinguish between the subpar 5G and the 5G that is over hyped.

After many conversations with Apple, I believe that what Apple is calling "the 1-bar symptom" is caused by "the choice of network thresholds by the Carrier which can force the device to stay on an LTE band with a weaker signal." Apple sent a field engineer to my house to collect logs using multiple devices including several iPhones and an Android device. Apple then contacted Verizon to optimize their configuration for my location. I have a stronger signal since they did this. Obviously the carriers (not just Verizon) need to do this for their whole network, not just one location.

I also found that WiFi calling wasn't working. Apple suggested that I disable QoS on my router, and now I can use WiFi calling. On one of my iPhones the change was instant; on our other iPhone, we had to remove the SIM card and then replace it to get WiFi calling working. Further, Apple says the the "no-bar symptom" was also caused by having QoS enabled. 

****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

Yes, there are a lot of 12 phones with the same issue. My problem with weak signal and signal dropping completely (no bars) was solved when 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. Others have posted more detail about this, but I believe that until the cell carriers change the way they're connecting to these new phones, we'll continue to have these issues.

[Email Edited by Moderator]

This is a hardware problem. After two weeks of yelling and cursing both T-Mobile and Apple , they finally relent to give me another phone with a disclaimer from the Apple tech that he could not guarantee that it will work. So it was a let down but what choice do I have ? So I took the new phone and walah! It worked! The signal is smooth! No more signal problems!

I had the exact same problem as the op and I stopped it with an LTE only sim card. My Iphone 12 Pro was losing signal and then it would say "Iphone not activated," requiring me to cycle airplane mode. I purchased my phone brand new from Visible(Verizon) and I have spent the last week going back and forth with them. We did a factory reset, reset network settings, re-provisioned, nothing worked. It was referred to the networking team, but they didn't know what to do either, and they finally sent a shipping label to return the phone.

Here's where it gets interesting. I put an active H2O LTE sim card in the phone, just for the heck of it, and the phone works perfectly now. No more lost signal - no more activation prompts. With H2O currently being LTE only, this leads me to believe that there is a problem with the 5g part of the phone. This might also explain why a few people have had success turning off 5G.

joxesCA wrote:

But when I see Searching on the iphone screen and I look at the other device I have to benchmark running on a different os this device shows full reception.

Which is precisely what you would see if the iPhone 12 has been instructed to use a frequency band your other phone cannot access.

Think of how this works - only the very newest phones can access those bands, so from the tower's point of view, those bands are the least crowded.

It then says "Hey, no one is using frequency band X, and your device can access it, so go use X."

Unfortunately, something in the tower equipment or antenna is not set up to properly work with X.

This doesn't resolve itself until the carrier either addresses the issue at the tower, or issues a carrier settings update to tell your phone not to report that it can operate on band X.

I admit, I don't know for certain this is what is happening, but it certainly matches all the symptoms worldwide.

It is seemingly more of an issue for users on Verizon with 5G on their plans because of the way they utilize LTE DSS:

PC Magazine: Here's Why Verizon iPhone Users Must Turn Off 5G Right Now

which from the tower's point of view would once again want to use "lightly loaded" band X.