Apple schematic diagram in PDF for logic board 820-2494, listed with the LB# prefix in the name. Apple numbers its logic boards in the 820- series, and the same number is usually printed near the board edge, so match it before relying on the drawings. No model or revision is stated in the name. The schematic shows power rails, the SMC and power sequencing circuits and signal paths between chips, making it the reference for diagnosing no-power faults, finding shorts and checking component values, ideally paired with the boardview.
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 @alischematics. Enginerys does not host this file.
All sources (3)
The same file was posted more than once. If one link is dead, try the next.
| Channel | Posted | |
|---|---|---|
| @alischematics | 13 Sept 2021 | Open file on RM Schematics |
| @pepeelectronica | 28 Apr 2022 | Open file on RM Schematics |
| @schematics_bios | 3 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.