Viewing the light path diagnostics LEDs

Use this information to locate and identify the light path diagnostics LEDs.

Before you work inside the compute node to view light path diagnostics LEDs, read Safety and Installation guidelines.

If an error occurs, view the light path diagnostics LEDs in the following order:

  1. Look at the control panel on the front of the compute node.
    compute node control panel buttons and LEDs
    • If the check log LED is lit, it indicates that a condition that causes an event to log in the IMM event log has occurred.
    • If the fault LED is lit, it indicates that an error has occurred; view the light path diagnostics panel and LEDs to isolate the failing component.
    • If the I/O expansion unit fault LED is lit, it indicates that an error has occurred in an I/O expansion unit that is installed in the compute node; check the IMM or CMM event log and the light path diagnostics LEDs to isolate the failing component.
  2. To view the light path diagnostics LEDs, select one of the following procedures:
    • You can view the LEDs through the CMM led command, the CMM web interface and the Lenovo XClarity Administrator application (if installed) or Flex System Manager management software (if installed).
    • If you are in the same location as the compute node, you can complete the following steps:
      1. Remove the compute node from the Lenovo Flex System chassis, (see Removing a compute node from a chassis for instructions).
      2. Carefully lay the compute node on a flat, static-protective surface.
      3. Open the compute node cover (see Removing the compute node cover for instructions).
      4. Remove the air baffles installed over the DIMM connectors.
      5. Press and hold the power button. When you press the power button, LEDs on the light path diagnostics panel and the system board will be lit if there are any hardware-related issues.
        Note: The power source for light path diagnostics is designed only to last a short time. If you press the power button and the light path diagnostics LED lights, light path diagnostics is charged to light the LEDs.

The following illustration shows the LEDs on the light path diagnostics panel.


Graphic illustrating the LEDs on the light path panel.

The following illustration shows the locations of the light path diagnostics LEDs on the system board.


Graphic illustrating the light path only LEDs on the system board