Firmware dump for the Apple MacBook Pro 15-inch A1286, Mid 2009 model, logic board 820-2523 revision B, project code K19. The RAR archive is 1.39 MB and should contain the EFI boot ROM image used when a board will not chime or show video after a corrupted flash. Technicians write it to the SPI chip with an external programmer such as a CH341A or RT809. Read and save the original chip contents first, confirm the 820 number on the PCB, and check that the image size matches the flash capacity before writing.
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 @biosarchive. Enginerys does not host this file.
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 →