Apple J17 MLB schematic, drawing number 051-9884, for logic board 820-3478-A, delivered as a PDF inside a RAR archive. It shows the full circuit, including power sequencing, rail names, connector pinouts and signal paths. Repair work usually combines it with the boardview of the same board to measure voltages at the right points and track missing rails. Apple prints the 820 number on the PCB, so verify the number and revision letter match before following component references or values.
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 | 27 Oct 2021 | Open file on RM Schematics |
| @LaptopsBoardview | 13 Nov 2021 | Open file on RM Schematics |
| @pepeelectronica | 26 Apr 2022 | Open file on RM Schematics |
| @generalschematics | 19 Oct 2024 | Open file on RM Schematics |
| @cyberlanelectonik | 16 Jul 2026 | Open file on RM Schematics |
| @schematics_bios | 25 Jul 2026 | Open file on RM Schematics |
| @schematics_bios | 2 Aug 2026 | Open file on RM Schematics |
| @schematics_bios | 14 Aug 2026 | 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.