Troubleshooting Light path diagnostics

Resolving The Problem

If the System Error light in the operator information panel on the front of the server is on, one or more LEDs inside the server may be on. Use the light path diagnostics to identify the type of error that occurred.

You can use the Light Path Diagnostics built into the server to quickly identify the type of system error that occurred. The Light Path Diagnostics panel is located on the system board just behind PCI adapter slot 1. When you press on the Light Path Diagnostics button the LED on the top right corner of the panel will illuminate. This shows that the diagnostic circuitry is working correctly.

The server is designed so that any LEDs that are illuminated can be re-illuminated without AC power after you remove the cover. This feature helps you isolate the problem if an error causes the server to shut down.

Note: You have up to 12 hours to use the Light Path Diagnostic LED's after AC power has been removed from the server. After 12 hours you must power the server up again to be able to use the Light Path Diagnostic LEDs to help locate system errors.

Viewing the LEDs on the system board

1. Turn off the server and any peripheral devices.
2. Remove the cables.
3. Remove the server from the rack and place it on a flat, non-conductive surface.
4. Remove the server cover.
5. Press and hold the Light Path Diagnostics (blue) button on the diagnostics panel.
6. The LEDs will illuminate while the switch is pressed.
   
   Note: You can illuminate the LEDs for a maximum of two minutes. After that time, the circuit that powers the LEDs is exhausted.

Diagnostics panel
The following illustration shows the LEDs on the diagnostics panel on the system board.

Light Path Diagnostics

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