Dell U3525 manual Diagnostic Lights, Error Messages

Code	Cause
4-2-1	No timer tick
4-2-2	Shutdown failure
4-2-3	Gate A20 failure
4-2-4	Unexpected interrupt in protected mode
4-3-1	Memory failure above address 0FFFFh
4-3-3	Timer-chip counter 2 failure
4-3-4	Time-of-day clock stopped
4-4-1	Serial or parallel port test failure
4-4-2	Failure to decompress code to shadowed memory
4-4-3	Math-coprocessor test failure
4-4-4	Cache test failure

Error Messages

NOTE: If the message is not listed, see the documentation for either the operating system or the program that was running when the message appeared.

If an error occurs during start-up, a message may be displayed on the monitor identifying the problem. See "Error Messages" in the User’s Guide for suggestions on resolving any problems.

Diagnostic Lights

CAUTION: Before you begin any of the procedures in this section, follow the safety instructions

located in the Product Information Guide.

To help you troubleshoot a problem, your computer has four lights labeled "A," "B," "C," and "D" on the front or back panel. The lights can be yellow or green. When the computer starts normally, the lights flash. After the computer starts, all four lights display solid green. If the computer malfunctions, the color and sequence of the lights identify the problem.

Quick Reference Guide

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