Use this information to diagnose possible errors that are indicated by the light path diagnostics LEDs.
The following table describes the LEDs on the light path diagnostics panel and the light path diagnostics LEDs on the system board. See Viewing the light path diagnostics LEDs for information about lighting the LEDs.
| Lit light path diagnostics LED | Description |
|---|---|
| None | The compute node is not sufficiently charged to display the LEDs on the system board. |
| Battery error | The system CMOS battery is not installed or is not working. |
| DIMM error x | A memory error occurred. |
| I/O expansion unit (SEE EXP) | An error has occurred with the I/O expansion unit. Check for error LEDs on the I/O expansion unit. |
| Light path diagnostics (LP) | The power source for the light path diagnostics LEDs is charged. |
| Light path diagnostics (LP) only | No errors have occurred. |
| Memory (MEM) | A memory error has occurred. |
| Microprocessor x error (CPU X) | The IMM2 lights this LED when a microprocessor has failed or overheated or the start microprocessor (CPU 1) is missing. The fault LED on the front panel is also lit. |
| Mismatch (MIS) | The microprocessors are mismatched. If the Memory LED is also lit, the DIMMs are mismatched. |
| NMI | The system board has failed. |
| SAS backplane error (STOR BP) | A hard disk drive backplane error has occurred. |
| System board (SYS BRD) | The system board has failed. |
| Temperature (TEMP) | The system temperature has exceeded a threshold level. |