Main logic board schematic for the Apple iMac 27-inch, model A1312, identified in the name by the K23 project code and MLB designation. The PDF, about 1.6 MB, covers the desktop's motherboard circuits, useful for tracing standby and main power rails, checking the SMC-related signals and locating parts around a short. Apple numbers its boards with 820- part numbers, so compare the number on your logic board against the schematic pages before trusting values, as A1312 machines were built in more than one generation.
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 (11)
The same file was posted more than once. If one link is dead, try the next.
| Channel | Posted | |
|---|---|---|
| @schematicslaptop | 26 Dec 2017 | Open file on RM Schematics |
| @LaptopsBoardview | 4 Jun 2019 | Open file on RM Schematics |
| @freeschematicdiagram | 9 Jun 2019 | Open file on RM Schematics |
| @hrtechno | 4 Feb 2020 | Open file on RM Schematics |
| @alischematics | 13 Sept 2021 | Open file on RM Schematics |
| @alischematics | 6 Jan 2023 | Open file on RM Schematics |
| @generalbios | 8 Oct 2023 | Open file on RM Schematics |
| @generalschematics | 19 Oct 2024 | Open file on RM Schematics |
| @boardviewsandachematics | 1 Sept 2025 | Open file on RM Schematics |
| @cyberlanelectonik | 14 Jul 2026 | Open file on RM Schematics |
| @schematics_bios | 13 Aug 2026 | Open file on RM Schematics |
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.