Dell T7400 manual Diagnostic Lights, Diagnostic Light Codes During Post, Light Pattern

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 18). 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	Plug the computer into a working electrical
	a normal off	outlet and press the power button.
	condition or
	a possible pre-BIOS
	failure has occurred.

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

•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).

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