Power sequence document for Apple logic board 820-01598, a 241 KB PDF. Apple uses the 820-xxxxx format for its logic board part numbers, printed on the PCB itself. The sheet shows the order in which rails and enable signals come up, from the always-on supplies through to the main rails, helping you find where a board stalls when it draws low current or will not boot. Use a multimeter or oscilloscope to check each step, and confirm the 820 number on your board matches.
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 @notebookschematic. Enginerys does not host this file.
All sources (2)
The same file was posted more than once. If one link is dead, try the next.
| Channel | Posted | |
|---|---|---|
| @notebookschematic | 20 Jan 2023 | Open file on RM Schematics |
| @schematiclaptopramkushwaha | 13 Sept 2025 | Open file on RM Schematics |
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.