Dell WHL, WHM manual = yellow = green = off, Diagnostic Light Codes Before Post

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Diagnostic Light Codes Before POST

Light Pattern					Problem Description	Suggested Resolution
				off	No electrical power is	Connect the computer to an electrical outlet. Ensure
				off	supplied to the computer.	that the front-panel power light is on. If the power light
						is off, ensure that the computer is connected to a
				off
A	B	C	D			working electrical outlet and then press the
				off		power button.
						If the problem is still not resolved, contact Dell for
						technical assistance.
				yellow	The computer is in a normal	Press the power button to turn the computer on.
				off	off condition; the computer	If the computer does not turn on, ensure that the front-
					is connected to an
A	B	C	D	off		panel power light is on. If the power light is off, ensure
					electrical outlet.
						that the computer is connected to a working electrical
				off
						outlet and then press the power button.
						If the problem is still not resolved, contact Dell for
						technical assistance.
				yellow	The computer is in a reduced	Use one of the appropriate methods to "wake up" the
				yellow	power or "sleep" state.	computer. See "Advanced Features" in the User’s Guide.
A	B	C	D	off		If the problem is not resolved and you are trying to wake
						the computer with a USB mouse or keyboard, substitute
				off
						the mouse or keyboard with a working PS/2 mouse or
						keyboard and then try to wake the computer.
				yellow	The BIOS is not executing.	Ensure that the processor is seated correctly and restart
				yellow		the computer.
A	B	C	D	yellow		If the problem is still not resolved, contact Dell for
						technical assistance.
				off
				off	A possible power supply or	Perform the procedure in "Power Problems" in the
				yellow	power cable failure	User’s Guide.
					has occurred.
A	B	C	D	off		If the problem is still not resolved, contact Dell for
						technical assistance.
				off
				off	A possible system board	Contact Dell for technical assistance.
				off	failure has occurred.
A	B	C	D	yellow
				off

= yellow = green = off

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