Chosen Solution
I have an iPhone 6 plus logic board and as soon as I plug it in it gets hot real quick(within a minute). Also there is no display when I turn it on. I bought it as a no power phone and found out that the battery that came with it was bad, so I replaced that. So now the phone turns on but overheats and does not display anything. I have looked all over for answers but can’t find anything.
You bought this phone advertised as having “no power”? Is it water damaged? Check for White/Red oval stickers. If they are red or missing, then it is water damaged and it could have all sorts pf problems that would cause overheating (shorts). It could be in the backlight circuit or PMIC. Ideally, you need to start probing the logic board to understand what is going on. The schematics can be found on the web. Otherwise, this may be more suited to a repair shop that does micro-soldering repairs.
Found out that there was a chip that was causing a short on PP_VCC_MAIN. In ZXW tools the chip is U1401(Don’t know the name of the chip though) and thats the area where it was getting really hot(used freeze spray to figure this out). So I removed it and now the short is gone. Thanks everyone for the help!
