Chosen Solution
This issue appeared after I reassembled the phone after replacing the screen. The screen was tested before installation and the phone had no issues turning on then. The battery is not discharged(tested with multimeter) and is at 4V. I’m not even sure which part could’ve been disturbed to cause this, the motherboard was removed before I pried the old screen off and put the new one on. The USB port somehow reacts to the connection and even if I disconnect it the booting issue remains, so it most likely isn’t the culprit? During the booting attempt(not really a bootloop) something (processor?) under the EMI shield is heating up, so I can assume that it’s trying to do something. I had set this project aside for 5 months, but I really do want to figure out what is wrong and fix it, even if it is only for the experience. No local repair shops offer support for the ROG series and a new motherboard costs more than a new phone and no schematics for the Asus Rog Phone 3 are available online, so I can only try to increase my own knowledge and dig deeper. Attempts at turning on can be seen here: https://vimeo.com/659448848
Hi, I haven’t checked it out but here’s a link to the schematics for a ZS661KS that may help.
