Chosen Solution

I didn’t use my 2017 13" MBP for a while and now that I wanted to use it again I encountered some problems.first of all it has developed so severe flexgate that the internal display is completely unusable and it is in weird state where it doesn’t truly turn off (when I hold the power button the display and trackpad turns off but when I turn it back on it starts really quickly and doesn’t do a boot chime)When I plugged it into my monitor (LG Ultrafine, so definitely not the cause of the problem), it turned on but didn’t get any signal (panel is turned on but black).It showed the battery empty sign so I let it charge (on its brick not the monitor, even tough that normally works), after a couple hours on the charger it was really hot, so I decided to let It cool off, but after I returned a while later its fan was maxing out and it was still very hot.That’s when I decided to open it up and unplug the battery, but even after that it still didn’t work with the LG, so I plugged it into my TV with a dongle and recived a signal, but only when the dongle was actively powered. The signal sadly was only the low battery warning again, so I plugged the power (which was previously in the dongle) directly into the Mac but after that I never got a signal again.after all that I decided that the data on the Mac ist lost anyway, so I tried to factory reset it, due to the flexgate I can’t do it on the device itself so I plugged it into my 2021 MBP but when the MBP or the LG is plugged in I can’t wake it and therefore can’t get it into DFU mode. Edit: It now boots again and the flexgate is back to what is was before (1/6th of the screen is black compared to weird glitching all over) This is the report it produced: MCA Error Report

this is the report from coconutbattery (it is fluctuating quite a bit: shortly after the screenshot it went up to 70%).it obviously is far from ideal but it shouldn’t cause such an issue and it isn’t physically swollen

DFU mode requires a second Mac which is connected via USB-C cable as explained here DFU Mode on Mac: What it is and How to Enter it And you are very limited on what you can do, It’s intended to fix a firmware error and you can only re-burn only some of the firmware blocks with the same CRC based block. And then the internal security check-sum needs to be validated Apple did a very good job preventing anyone from installing backdoors into the users space. From what you are stating your battery is gone and you might have additional damage within the logic board as running the battery to death tends to over stress the charging logic in this series when you try to charge a fully dead battery. MacBook Pro 13" Retina (Function Keys, Late 2016-2017) Battery and the guide MacBook Pro 13" Function Keys 2017 Battery Replacement Here’s the needed steps to diagnose your logic board A1708 Macbook Pro 20v 0amps not turning on Louis jumps over the port MUX chips to the PPBUS issue which is a common issue of a shorted out cap. I would focus my efforts on these.

First and foremost, there’s no DFU mode on a A1708 Mac, thus whatever you try you won’t get into DFU. If the board works, you should be able to getting into recovery mode at startup, regardless if the battery is disconnected. From your description you seem to have a full array of different issues that would seem to head straight to liquid damage or some kind of high level damage. Remove the board, inspect with microscope and reassess to start with.