Diagnostic Lights

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

To help troubleshoot a problem, your computer has four lights labeled 1, 2, 3, and 4 on the front panel (see "Front View (Tower Orientation)" on page 11 or "Front View (Desktop Orientation)" on page 15). When the computer starts normally, the lights flash, and then turn off. If the computer malfunctions, use the sequence of the lights to help identify the problem.

NOTE: After the computer completes POST, all four lights turn off before booting to the operating system.

Diagnostic Light Codes During POST

Light Pattern

Problem Description Suggested Resolution

The computer is in a normal off condition or a possible pre-BIOS failure has occurred.

A possible BIOS failure has occurred; the computer is in the recovery mode.

Plug the computer into a working electrical outlet and press the power button.

•Run the BIOS Recovery utility, wait for recovery completion, and then restart the computer.

•If the problem persists, contact Dell (see "Contacting Dell" in your User’s Guide).

A possible processor

• Reseat the processor (see "Processor"

failure has occurred.

in your User’s Guide).

 

• If the problem persists, contact Dell

 

(see "Contacting Dell" in your User’s

 

Guide).

Quick Reference Guide

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