Dell T5500 Power Button Light Codes, Diagnostic Light Codes, Pre-POST Diagnostic Light Patterns

2.If a problem is encountered during a test, a message appears with an error code and a description of the problem. Write down the error code and problem description and follow the instructions on the screen.

3.If you run a test from the Custom Test or Symptom Tree option, click the applicable tab described in the following table for more information.

Tab	Function
Results	Displays the results of the test and any error conditions encountered.
Errors	Displays error conditions encountered, error codes, and the problem description.
Help	Describes the test and may indicate requirements for running the test.
Configuration	Displays your hardware configuration for the selected device.
	The Dell Diagnostics obtains configuration information for all devices from system setup, memory, and various internal tests, and it displays
	the information in the device list in the left pane of the screen. The device list may not display the names of all the components installed on
	your computer or all devices attached to your computer.
Parameters	Allows you to customize the test by changing the test settings.

4.When the tests are completed, if you are running the Dell Diagnostics from the Drivers and Utilities disc, remove the disc.

5.Close the test screen to return to the Main Menu screen. To exit the Dell Diagnostics and restart the computer, close the Main Menu screen.

Power Button Light Codes

The diagnostic lights give much more information about the system state, but legacy power light states are also supported in your computer. The power light states are shown in following table.

Power Light	Description
State
Off
	Power is off, light is blank.
Blinking Amber Initial state of light at power up.
	Indicates system has power, but the POWER_GOOD signal is not yet active.
	If the Hard Drive light is off, it is probable that the power supply needs to be replaced.
	If the Hard Drive light on, it is probable that an onboard regulator or VRM has failed. Look at the diagnostic lights for further information.
Solid Amber	Second state of the light at power up. Indicates the POWER_GOOD signal is active and it is probable that the power supply is fine. Look at
	the diagnostic lights for further information.

Blinking Green

System is in a low power state, either S1 or S3. Look at the diagnostic lights to determine which state the system is in.

Solid Green

System is in S0 state, the normal power state of a functioning machine.

The BIOS will turn the light to this state to indicate it has started fetching opcodes.

Diagnostic Light Codes

Four (4) single color lights are incorporated on the front control panel to serve as a diagnostic aid for troubleshooting systems exhibiting No Post/No Video symptoms. The lights do NOT report runtime errors.

Each light has two possible states of OFF or ON. The most significant bit is labeled with the number 1, and the other three are labeled 2, 3, and 4, as you go down or across the LED stack. The normal operating condition after POST is for all four lights to be ON and then turn off as the BIOS hands over control to the operating system.

Pre-POST Diagnostic Light Patterns

State	Light Pattern	Light	Power	State Assignment	State Description
	( 1 2 3 4 )	Description	Light
		1- Off
Pb0a		2- Off		System	System is not plugged into AC, PSU is not plugged into system board, or control
		3- Off		Unplugged	panel not connected to system board.
		4- Off
		1- Off
Pb0b		2- Off		ACPI S0; Normal	System is on with no failures detected. This is actually a BIOS controlled state and is
		3- Off		Operation	also S0e.
		4- Off
		1- Off
Pb0c		2- Off		ACPI S1	Windows Standby State.
		3- Off
		4- Off
		1- Off
Pb1		2- Off		ACPI S4 or S5	Hibernate or Soft off. System plugged in, but either turned off or in Windows
		3- Off			Hibernation State.
		4- Off