iPad Pro continues to power cycle after battery replacement.

Hi Kyle,

Believe it or not, it actually sounds like you're making progress. I agree with Gorilla that this does sound like a battery issue and we'll address that in a minute.

First I'd like to introduce you the the concept of a kernel panic. That phrase describes the sequence of events that occurs on an iOS device when it encounters an unrecoverable error. Generally that happens when the operating system goes through its sensor scan procedure, which happens every three minutes. If for some reason it has a problem with any given sensor, it logs the error and then reboots the phone in an attempt to recover from the error.

Of course, the problem here is that with a hardware error, the next time it goes to scan the sensors, the error will still be there and will result in another kernel panic, saving the log file and rebooting the phone. We haven't gotten to the point where the phone is actually smart enough to say to itself, "Hmm, I've rebooted a dozen times and the problem is still there, so rebooting again probably isn't going to help", and as a result it will continue rebooting to infinity and beyond.

The key part of this is the log files I mentioned. Those are stored on the phone, and with three minutes between reboots, it's actually enough time to get to one of the files and see what's in it. The excellent Kernel Panic wiki page authored by our very own Alisha (@flannelist) has instructions on where to go and how to get to those files.

iPhone Kernel Panics - iFixit

So I'd say the next step for you is to read through the wiki page and locate the latest panic log, then come on back here and add the first page or so to your question via cut and paste, a screenshot or a photo. That information should point us in the direction of exactly what's causing the iPad to reboot and from there we can recommend a course of action.

Now, that all being said, based on the existing information we have, it does sound like an issue with the battery communication. There's a small circuit board built into the battery called the BMS, or Battery Management System, that has things on it like the temperature sensor along with ways to determine the battery health and voltage and/or current sensors. So the motherboard has to communicate with the battery in order to work correctly, which it doesn't sound like yours is doing.

Although @xingxing is absolutely correct that either of the problems they mentioned could cause what you're seeing, there's a third possibility that's much more common, and that's damage to the connector on the battery. We tend to see it happen during the step where you insert a battery blocker to disconnect the battery while you are in the process of removing the screen. There are three extra pins on the battery connector that are used to communicate with the BMS, and if those get bent or broken, then you get behavior like what you're seeing. Here's a picture of those pins.

If one of those pins isn't making contact for some reason, that would explain what's going on. It's not quite as likely of an explanation in your case since you're using a brand new battery, but whenever you use the battery blocker there's a possibility of damage to those pins.

I hate to suggest it, but once you have the panic logs and we've had a chance to take a look a them, I'd say you are probably going to have to take the whole thing apart again and remove the battery so you can verify that the pins are intact and not damaged. Let's get those logs first, then we can talk about what to do next, though. Here's how to add that information to your question.

Adding images to an existing question - iFixit Repair Guide