I am not sure, it is certain that heat makes it usable though.

It first began when it lost USB data transfers, I was like that for months, I thought I needed to replace the USB module as many users claimed that to be the solution, I didn't, another common failure with this device is that the flex cable fucks up after a while, so you either replace it or add something to make pressure to the board and charging/USB module, I did the latter, applied black tape to both ends like 3 years ago or so, quick and normal charge worked since then, so I assumed USB data transfers failing me months ago was a symptom of my workaround giving up... Turns out it wasn't.

Then after months I lost IMEIs, so no data transfers, I said, oh, I could use my phone as an iPod or something, but as this is my main device yet, I decided to look up for solutions, and playing around with QFIL, TWRP and lots of things (do note I had efs partitions backed up prior, which did nothing to help me), I was left without WiFi, so this one really hurts lol.

I forgot to say that when IMEI started to fail I detected that my phone USB data transfer worked for a while, so it was like a trade lol, that essentially gave me the opportunity to play around with it and flash something else.

Anyway, I said to myself, ok so be it, it would be a dumb phone (a very dumb one) no internet access whatsoever and USB data transfers gave up as well... I could load emulators or something (through BT perhaps) but as the partition image responsible of Wifi connection wasn't loaded properly from the kernel it started to hinder the performance of the device with some wifi process (detected with FKM) if I try to kill it then it is replaced by a kernel binder process which I can't kill (well I can but it auto starts), so yeah, having a phone that can't deep sleep and is always wasting resources on that doesn't seem smart...

Luckily the hairdryer and that Termux command (with quick charge) gave me everything back... Not all the times I get back USB data transfers (it seems like it is the 1st one to go when it loses connection) but I appreciate I can still milk this device that I got in November 2020 and somehow still can get 8 hrs of SOT from it (no gaming and with Wifi only).