I’m a novice to this experience but in short, I performed a backlash from the latest and final bios firmware BHCN45WW to BHCN26WW hoping that would solve an issue with keyboard functionality failing after an update. Ended up hanging during flash process and then system would no longer POST on reboot.
USB recovery process didn’t seem to take. So today I successfully managed to get the BIOS dump from my machine with the Ch143a mini programmer or whatever it’s called. I read the file twice, saved 2 versions, used hex editor to compare both files, it came back they were identical. I understand that before I can flash the stock bios from the Lenovo site which I extracted from the .exe and then pulled the 16mb bios region from that initial 17.6mb BIOS.fd file, I have to have the DMI information injected into the stock image.
At any rate, could anyone please help me with this?
Legion Y540-15IRH Laptop (Lenovo) - Type 81SX
S/N
PF261FGM
MTM
81SX012TUS
The untouched bios dump:
Thank you so much for this … Good news is that I managed to see my windows sign in screen and everything also with my info shows in the bios menu. Only thing is that the bios and the ec are mismatchednow…
It’s bios bhcn45ww but ec is bhcn27ww… Which is giving me a bit of problems…
I’m trying to see if I can I run the bios update utility for version 45 to take care of the mismatch as it flashes them together but I’m seeing users suggest not to…
I’m not sure what to do… Is there a way to do that?
Do you remember what the EC version was before you did the bios backflash? The BIOS version does not always have to be the same as the EC version!
If you want, you can trying running the BIOS updater. Worst case scenario if your laptop hangs again and the BIOS corrupts, you can just flash this BIOS I gave you again with your CH341A. Personally I’ve never heard of anyone having problems after running the BIOS updater but that just might be my inexperience.
Hello same happened to my Legion Y545, tryed to downgrade the Bios and ended in a back screen, it uses the same Bios file BHCN45WW, my keyboard is not working, thats why I try to downgrade the BIOS.. only the keys lightining work … but I think no other key, also tryed the flash USB format FAT 32 with the bin file you share and nothing happened. I try holding th Windoys key + R - nothing, and also tryed windows key + B… nothing. I just dont know what else to do… Thanks for the help
Is there any way to get do it with a USB in Fat32 format, some forum says to press Fn + R, other Fn + B, … also I can see this model has the Novo hole to pin with a paperclip, What do you think about it? thanks!!
after trying so many fixes and non-working
i have reverse engineered the firmware update and fixed it
you can download the fix and see my progress from my github : https://github.com/AMIRSRAD/Legion-Y540-Keyboard-Fix