Macintosh HDI-20 1.4 MB Drive Service Source

The Macintosh HDI-20 1.4 MB Drive Service Source is Apple's 18-page service manual for the external 1.4 MB floppy drive with an HDI-20 connector. The PDF was produced on 22 November 1995. Like other Service Source volumes it works at module level: symptom charts and take-apart procedures, with no board-level detail. Page numbers below are the PDF's.

Contents

• Troubleshooting: General (p. 3), Symptom Charts (pp. 4-5)
• Take Apart: Case Top (pp. 7-9), Drive & Ribbon Cable (pp. 10-12), Cable Interface Board (pp. 13-14), HDI-20 External Cable (pp. 15-16)
• Exploded View (p. 18)

What it settles

Apple's symptom chart (pp. 4-5):

Symptom	Apple's cures, in order
Drive does not appear on the display	Attach the drive while the computer is shut down, not in sleep; replace drive mechanism; replace external drive cable
Drive reads but does not write	Replace drive mechanism; replace external drive cable
Drive does not read	Check the software is known-good; replace drive mechanism
Drive does not eject a disk	Replace drive mechanism
Drive does not read, write or format MS-DOS disks	Format all disks on the MS-DOS drive first
Many file transfer errors, or drive fails to format	Clean the floppy drive; replace drive mechanism

The take-apart procedures show the drive's modules: case top (with the door and its retainer pins), drive mechanism and ribbon cable, cable interface board, and the HDI-20 external cable, which plugs into the cable interface board (pp. 7-16).

What this manual does not contain

There is no Basics or Specifications chapter: no capacity, data rate, current draw or mechanism model is printed. The exploded view names the four modules but gives no part numbers. There is no schematic and no component list.

Pages that cite this document

• Apple SuperDrive
• Apple SuperDrive/HDI-20 Service Source
• Macintosh Floppy Drive Maintenance
• Floppy Drive Repair

Download: Hdi20_1.4_drive.pdf (202 KB)