Same result as before, I left it for >30 minutes. Power LED stays on, CPU feels warm but nothing on screen or keyboard....

I tried it with and without the WWAN card installed. No luck.
The machine doesn't boot (nothing on screen, keyboard doesn't react to any combinations) but (as before) the backlight turns on and off when doing a power cycle....

My BIOS dump can be found here:
The S/N of my machine is MP1GVNSF, and it's a ThinkPad X380 Yoga type 20LJ. The model of my motherboard is LA-F421P rev. 1 date 2017-10-26....

I have a ThinkPad X380 Yoga that I tried to put a WWAN modem on (Fibocom L830-EB), this modem is supposed to be supported on the laptop (even the FRU P/N matches with Lenovo's part list), but the system wouldn't boot, saying there was an unauthorized network card installed. I tried patching the BIOS to remove the whitelist, but I just ended up bricking it.

Even after flashing my original dump, my machine refuses to boot. I know it's a valid dump because I've checked in UEFITool, and I've already tried replacing the BIOS region on the firwmare using ifdtool, the machine just doesn't...

Well. I'm a 18yo high school student from Mexico City, I study at UNAM (National Autonomous University of Mexico) and plan to major in compsci. I currently own an M1 MacBook Air, a ThinkPad X380 Yoga and a T460s.