Archive for the Apple A1419 iMac logic board 820-4652-A, project code J78, marked MLB CTX, compressed into an 11.3 MB ZIP. CTX usually denotes a configure-to-order build, though the archive contents are not listed, so check whether it holds firmware, schematic or boardview files. Apple numbers its logic boards 820-xxxx with a revision letter. Confirm the number on your board matches exactly, and if reflashing the boot ROM, back up the original chip first and verify the image size.
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 @schematicslaptop. Enginerys does not host this file.
All sources (8)
The same file was posted more than once. If one link is dead, try the next.
| Channel | Posted | |
|---|---|---|
| @schematicslaptop | 30 Mar 2021 | Open file on RM Schematics |
| @LaptopsBoardview | 29 Apr 2021 | Open file on RM Schematics |
| @pepeelectronica | 24 Apr 2022 | Open file on RM Schematics |
| @generalschematics | 19 Oct 2024 | Open file on RM Schematics |
| @boardviewsandachematics | 2 Sept 2025 | Open file on RM Schematics |
| @schematics_bios | 24 Jul 2026 | Open file on RM Schematics |
| @schematics_bios | 1 Aug 2026 | Open file on RM Schematics |
| @schematics_bios | 14 Aug 2026 | Open file on RM Schematics |
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