K3 Troubleshooting dead K3 via TTL (freezing after a few seconds?)

[pmdci]

First post (yay!)

So I have this dead K3 which I decided to try to revive (even though I have an Oasis).

So K3 would start and trying those reset commands holding home, etc wouldn't work most of the time. Is like it would freeze sporadically for no reason.

So I got a USB to TTL dongle and managed to get a steady connection to the UART pads using a strip of 3 serial Dupond wires, Kapton tape and a locking plier. The connection is very steady and I tested for continuity and shorts using a multimeter.

Using minicom (Fedora 41) I managed to connect to the K3 and see the boot output.

- There is no interference (gargabe) on the connection.
- I can get into the uboot prompt.

What I've noticed, however:
- uboot doesn't have a 'usb' command. Should it have it, so I can get the device in usb mode?
- The minicom session will always freeze after a little while. I noticed this whether I'm on the uboot prompt, if I'm letting the device start normally, or if I try to get into the RECOVERY mode by hitting enter at a given time.

Since the device seems to be freezing after 10-30 seconds (at least its UART interface is!) I wonder what can I try to salvage this device.

I am wary of trying to upload an image or anything like that, unless I can get a steady, continuous UART connection.

Any thoughts?

PS: The device has a new Amazon original battery from 2017. Seems to hold charge fine.