This boot loop problem was why I was very cautious about purchasing a "renewed" LG V20 from Amazon; I figured that many phones are turned in when buying a newer cell, and my luck might be that I'll pick up someone else's headache of a "loopy phone". My experience with Amazon's "renewed" phones has been VERY discouraging - three out of five defective, but for different reasons! I'm sure most users are aware of LG's problems with the V10 phone (the previous LG model) - many, many boot loop problems (~2015) before users started fixing their own phones. I've been lucky with this V20 as far as lack of loop boot problems are concerned. I would follow Nick's disassembly experience with the LG G4 if you have the proper equipment. (Page down on the reference page given by Nick; his solution is near the bottom.)