Firmware archive for the Apple A1502 MacBook Pro on logic board 820-3476, revision A, with cln in the name likely meaning a cleaned image, in a large 100 MB RAR. The 820-xxxx number is Apple's own logic board numbering and must match the board. The size suggests the archive holds more than a single EFI dump, so review it first. Technicians reprogram the EFI flash with a programmer to clear locks or corruption. Back up the original chip, which holds the serial number.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @bios_laptop. Enginerys does not host this file.
All sources (2)
The same file was posted more than once. If one link is dead, try the next.
| Channel | Posted | |
|---|---|---|
| @bios_laptop | 15 Jun 2022 | Open file on RM Schematics |
| @Satale_bios_esquemas_Laptop | 27 May 2023 | Open file on RM Schematics |
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →