File:Apple Hard Disk 20 Technical Procedures.pdf

Apple's Hard Disk 20 Technical Procedures, the Hard Disk 20 section of Apple Service Technical Procedures, Volume Six (Macintosh). 37 pages, sections revised October 1985 to November 1986. Contents: Section 1, Basics (setting up, switching on and off, initialising); Section 2, Diagnostics (Hard Disk Drive Diagnostic); Section 3, Troubleshooting ("things to remember", the troubleshooting flowchart and notes, startup problems and daisy-chaining problems); Section 4, Take-Apart (tools, top cover, controller board, bottom shield, fan, power supply, hard disk assembly); Section 5, Illustrated Parts List with Apple part numbers (rev. Feb and Mar 86). Described on Apple Hard Disk 20 Technical Procedures.

Module-level service only: no schematic, no power supply component values. Extracted from PDF pages 361 to 397 of the archive.org scan and converted to 150 dpi greyscale.

https://archive.org/details/apple-service-technical-procedures-volume-six (retrieved 2026-09-30)

Apple Computer, Inc.

Copyright Apple Computer, Inc., 1985, 1986. Hosted for preservation and repair reference.