Compaq 386 manual POWER-ON SELF-TEST POST/PROBLEM Isolation, POWER-ON SELF-TEST Post

Chapter 2

POWER-ON SELF-TEST (POST)/PROBLEM ISOLATION

Maintenance and Service Guide 2-1

2.1 INTRODUCTION

This chapter provides a list of the subassemblies that are tested by the Power-On Self-Test (POST), a list of steps that you should perform prior to going through the problem isolation procedures, and a problem isolation flowchart for quick reference.

2.2POWER-ON

SELF-TEST (POST)

A series of diagnostics tests automatically runs on every COMPAQ personal computer system when you turn on the system. These tests are called Power-On Self-Tests (POST).

POST checks the following subassemblies to see if the computer system is functioning properly:

□Power supply

□System board

□Memory

□Keyboard

□Controller boards

Turning on the computer automatically activates POST. If POST finds an error in the system, error codes (in the form of beeps) are heard or error codes (numbers) are visible on the monitor. See Chapter 5, ERROR MESSAGES AND CODES, for definitions of the error codes.