HP 14s-fq1010nm Black screen after BIOS update - cannot downgrade

[mitchw]

Just had a customer bring in a HP 14s-fq1010nm to do some maintenance.
After updating the BIOS to the latest (F.35) I get black screen (no backlight turning on). However the backlight turns on if I connect an external display to HDMI, but when booting to Windows, both displays remain black.
After disconnecting internal LCD, and plugging in external display via HDMI, it works on external.

I tried downgrading it using official method - using an USB drive with older BIOS version, but it fails, saying that the BIOS files are corrupted. I used about 5 different older BIOS versions with no avail.
It says: "The BIOS recovery files cannot be found or the files are corrupted.". If I use the same version BIOS it does recovery, but it does not solve the problem, as it just reflashes the same version.

Tried reading the bios with SOIC clip and always get bad reads, also the chip is 1.8V version. If I get a successful read, I will attach it here
Can anyone help?

Thanks

[SMDFlea]

Tried reading the bios with SOIC clip and always get bad reads, also the chip is 1.8V version. If I get a successful read, I will attach it here
Can anyone help?
Thanks

Desolder it and put it on/in an adapter. Why struggle with a clip

[mitchw]

I desoldered it, and of course I now got a good read.

I then flashed the blank (recovery) image as it was 16MB image with no branding data, and it updated the EC at startup.
And there was now image on display.
I then figured I should flash the original dump back and it worked!

So most likely the EC didn't get flashed and this is why there was no image on display...