820-01958 a2179 efi/bios question

yianaki

New member
Hello everyone!
I am new to this forum :)

I have a Macbook Air 820-01958 board. The logic board is actually ticking. (
) same as this.
So I am pretty sure the CPU is dead.

I have a question. I am going to swap boards with another macbook air 820-01958 (the only difference is the ssd size 256 vs 512).
I want to try and keep the same serial number, would swapping the efi/bios chip work in this case?

Thank you in advance!
 

2informaticos

Administrator
Staff member
First of all, welcome to the forum!

The serial number is inside U4770 (SoC ROM).
Read the chip, change the serial with any hex editor, then solder back U4770 on ITS board.
Do NOT forget to save the backup of your chip; before changing any data.

Be aware, this is 1.8V SPI chip.
 

yianaki

New member
Thank you so much!
I figured it would be easier to program it then to swap it.
I'll make sure to make multiple back ups. :)

Again thanks for the help!
 
Sorry to hijack this tread, not sure if its allowed but i have a question regarding this particular topic and it might help in future to have all in the same spot..

I just did exactly that - change the sn in the eprom, however now i am no longer able to restore the os, i am getting weird errors (-2003f, -2004f) after the connection and some time it goes as far as loading in to the installer but then it fail saying "was dont able toconnect to the server to retreview lock status" or something like that..
Any advises?
 

2informaticos

Administrator
Staff member
Put back the backup and check what happens.
If still the same, something else was affected by the heat applied to desolder/resolder U4770.
Check for knocked off components.
 
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