I suggest you remove the battery, unplug the button battery, wait a minute, and then plug the button battery and main battery back. Now you should be able to post. That's how I solve similar situation today....

I have a T480s running Windows 11, everything is working, but the BIOS is locked. So I purchased a CH341A programmer, read the chip 3 times to make sure it's right, and then patched it with the auto-patch tool. Unfortunately, the laptop refused to boot and played a melody. I had to write the original bin into the chip; otherwise, I can not use my laptop.
Would like to know why and how to patch it properly, files provided.

Model: T480s
Type: 20L8-S62100
SN: PC-11AMW1...

Hi, everyone, my name is Holstein, I was a reviewer on PC motherboards, and a big fan of ThinkPad laptops. I like hiking if I have the time, but I am really busy now since I am taking an MBA course.