VAXstation 3100 Model 76 Maintenance Guide

This document, "Order Number EK-VS31M-MG.002," published by Digital Equipment Corporation in May 1991, is a technical service guide for the VAXstation 3100 Model 76 (VS43A-xx) system.

It provides detailed instructions for troubleshooting, adjusting, and repairing the system down to the Field Replaceable Unit (FRU) level. The manual is specifically intended for Digital Customer Services personnel and self-maintenance customers.

Key areas covered include:

• Testing Procedures: Running power-up tests, self-tests, and system exerciser diagnostics.
• Troubleshooting: Steps to diagnose and isolate problems to specific FRUs, with dedicated sections for memory (DSIMM) and SCSI components.
• System Utilities: Descriptions and usage of tools like the diskette formatter, special diagnostic key creation, RX33 formatting, and console password features.
• FRU Removal and Replacement: Comprehensive procedures for servicing various system components, including disk drives, memory modules, graphics coprocessors, and the power supply.

The document also includes extensive appendices with recommended spare parts lists, detailed self-test and system test error codes, and diagnostic LED definitions.