820-3437-B SPI Bios chip replacacing

[air_chair256]

Hello everyone

I got a macbook air 820-3437-B with some liquid damage around U6100 and U1900, when you connect it to the charger the fans spin and green/orange light turn on and it light up USB mouse i tried to clean all the corrosion around U6100 and replaced U1900 but no luck then i replaced U6100 from another board same model then the device turns on, chime and showed apple logo but it stuck on apple logo i read some where i need to copy ME region from old Bios chip to the new one so i used programmer and copy and write ME Region from old to new chip and when i soldered the chip back on the board the device start acting like before ( fan spins orange light turns on and black screen ) i tried to reprogram the new chip using the same file that was on it from the beginning and once i put the original file for the new chip and soldered it back the device turns on and stuck on apple logo again, i tried third chip from different board tried to move ME region from old Bios to this chip too and once i move it the macbook stops turning on only fan spins and orange light. anyone have any idea what's going on? any help will be appreciated and sorry it's confusing couldn't explain it any better

Thanks

 

[dukefawks]

Upload the working BIOS and give me the serial number of the original board.

 

[air_chair256]

Thanks for your reply
here is the working Bios File link

https://www.4shared.com/file/ke0hsur8fi/820-3437-B-Good.html

and here is the Password for not working macbook air : C1MNQ370G086

 

[dukefawks]

BIOS with clean ME, your serial number, checksum corrected and PRAM cleared.

https://drive.google.com/open?id=1kPdGMPHkHwwIFRwPFelnEHyYC1IOE-Bu

 

[air_chair256]

Thanks heaps i programmed the Bios with this file and it worked, thanks so much for your help, i would appreciate if you answer one more question please: so in next time if i face same problem do i need to create a clean ME and write the serial in a working Bios and install it and it will work?

thanks

 

[dukefawks]

The way to create a clean ME as found on various websites is completely wrong, they have no idea what they are doing. It will break many things including webcam, LAN, etc. Just editing the serial number will give an error when you run a hardware test as the checksum on the Fsys block is no longer correct.
Explaining how this all works is way too complicated for the few times you may need this. The easy solution is to buy a "Medusa" from Chipmunk so you can mess around with it yourself. They are not cheap though! It will however fix the ME, correct Fsys checksum and remove EFI lock, etc.

http://www.cmizapper.com