Why does my phone turn off when unplugged from charger?

"When the Tigris IC detects that there is power from the Lightning port, it allows the USB voltage to power the device instead of the battery. The U2 IC (Tristar) is the one that controls charging. Typically, when an iPhone or iPad exhibits no-charge or fake-charge, it is a Tristar problem.

@migo99 , it would be nice to know what chip exactly was replaced last time. Was it a Touch IC chip or something else? Did you phone work properly after that repair?

Do you have a known-good battery or can you charge your current battery in an other iPhone 6? That would help us eliminate one variable.

Otherwise, based on your comments, it appears to be a charge problem (U2). You need to find a qualified repair shop that does micro-soldering repairs for a proper diagnostic."

It seems like it needs a new battery. Any water damage? Do you use an original apple cable or a replica?

definetly a bad battery

I had this same problem. I was going to go get a new battery but when i added more iCloud storage it started to stay on off the charger. Not sure if i fixed the problem but i haven’t had the problem since.

I am facing the same problem with my iphone 7 , i have no clue about what to do. Somebody please suggest a solution its just been 3 months

i did all the methods to restart my phone…. but it keeps doing the apple logo loop… never turns on it only does the apple logo when its plugged into a wall port…it doesn’t come on at all when i plug it into the computer to do the update method… WHAT DO I DO ??