Why is my phone restarting every 3 minutes?

Hi Alysa,

The three minute reboot cycle is a vital clue as to what's going on with your phone. That just so happens to be the amount of time between when the phone scans all its internal sensors. What's happening is that three minutes after it boots, it goes to check all its sensors, and it finds one that's not working. Apple has apparently decreed that not being able to read a sensor is an unrecoverable error, so it initiates what's called a kernel panic. The panic results in writing a log of the conditions that caused it followed by rebooting the phone. Of course, the problem is, since it's an actual hardware error, that means its still there the next time the sensors are scanned so it reboots again - and again - and again...

So what we need to do is go get one of those panic logs and find out what's causing the reboot. Alisha ( @flannelist ) has written the definitive guide here on iFixit to kernel panics that will show you how to access the panic logs and how to interpret them.

iPhone Kernel Panics - iFixit

Your assignment is to read the wiki page and use that information to locate your panic logs. Copy/paste or screenshot the first page or so of the newest one available then come back here and add that information to your question. You've got three minutes to accomplish that; I've done it myself so it's quite doable.

Adding images to an existing question - iFixit Repair Guide

Once we have the kernel log we can use it to figure out which sensor is causing the problem and thus what you will need to replace in order to fix it.

Okay, good work Alysa! Here's the smoking gun in your panic log.

Missing sensor(s): mic2 Prs0

This is an unusual one in that you've got two sensors from two separate parts of the phone. I can tell you how to fix each one individually, but to be honest I'm a little suspicious as to why those two failed at the same time. You mentioned that nothing has changed with the phone lately; there hasn't been any issues like being dropped, getting wet or a new OS update?

Alisha ( @flannelist ), have you run into this before? I'm at a loss to explain how two separate I2C lines and/or their sensors could go bad at the same time.

The Prs0 is a pressure sensor connected to the barometric vent on the bottom of the phone. It's part of the lightning port flex cable assembly and is replaceable, although to be honest it is a bit of work. Here's the guide showing how to replace it.

iPhone 11 Lightning Connector Assembly Replacement - iFixit Repair Guide

The mic2 sensor, on the other hand, is located on the power button / flash flex cable assembly. That requires an entirely different set of instructions to replace it, and unfortunately iFixit doesn't have that particular guide available. However, there's a Spanish site called Nadie Me Llama Gallina that has just what you need.

Manuales / Apple iPhone 11 / Power button, flash and top microphone

Let's wait and see if Alisha has anything to add here, but otherwise if it was my phone I'd start out with replacing both of those parts and see what happens after that. The problem is, if those parts don't do the job then you're probably looking at a logic board repair with requires a high degree of expertise and sometimes very specialized equipment, so lets hope that's not the case.