HP EliteBook 850 G8 - Error code / Caps Lock permanently on and blinks twice every 6 seconds

[Curtissimo]

Hi everyone.

I have a HP Elitebook 850 G8.
Serial: 5CG2324XM0
ProdID 6L8D5EC#ABA
It has a Winbond W25Q256JVEN Chip.

I need to remove BIOS Password.

I made a dump with an CHA341A programmer and NeoProgrammer 2.2.0.10.

Attached my dump.

I also used the HP Unlocker tool to create an unlocked file (I followed the guidelines)

I also downloaded latest HP BIOS Update (SP158137) which includes 3 .bin files. I found the Number T76 in my original dump, so I used: T76_01210000.bin

What I did:
1) Make dump of original
2) Erase IC, Write IC with Unlocked file from HP Unlocker v1 --> didn't work, CAPS Lock Error Code
3) Erase IC again, Write IC with T76_01210000.bin file from HP. This file has 32324 KB instead of 32768 like my dump or the unlocked file. Does this matter? --> didn't work, CAPS Lock Error Code, Black Screen, PC doesn't boot
4) Try to boot the Laptop without BIOS soldered at all. Of course, didn't work, I expected this, it seems like exactly the same Error code. I attached a short video.

I try to check the connections of the pins now. I assume there is a problem with a proper connection between bios and motherboard.
I don't assume the chip is broken, otherwise I wouldn't be able to read and write the IC with the programmer, right?

I would go ahead and reflash my original dump, just to make sure it's not the flashed data which is the source of the error (It could be possible that BIOS not recognized and BIOS corrupt bring up same Error code???)

Any thoughts?

Thanks.
Curtissimo

[Curtissimo]

Sorry, if I missed the edit function:

Short update: Flashing original dump back with all options checked in NeoProgrammer (Off-Protect, Erase, Blank-Check, Write and Verify) ended up that I don't see usual error code (permanent Caps Lock with twice blinking every 6-7 seconds). As soon as I hold the Power Button for 5-10secs and release it, Caps Lock lights for 3-5 seconds and goes off again. Nothing more happens.

Now I'm pretty lost....

[Curtissimo]

I took the chip out again and soldered it back just to make sure it's not a connection problem. Same behavior with current flash (original dump): I hold power button for 12 seconds, then CAPS LOCK and my battery LED are on for 5 seconds. Afterwards all lights go off. Nothing happens. Black screen.