Light path diagnostics LEDs

The following table describes the LEDs on the light path diagnostics panel and suggested actions to correct the detected problems.

For additional information, see Server controls, LEDs, and power and the System-board LEDs for the location of the system board LEDs.

Note: Check the IMM system-event log or system event log for additional information before replacing a FRU.
Table 1. Light path diagnostics panel LEDs
  • Follow the suggested actions in the order in which they are listed in the Action column until the problem is solved.
  • If a action step is preceded by "(Trained technician only)," that step must be performed only by a trained technician.
LED Description Action
None, but the Check Log LED is lit. An error has occurred and cannot be isolated. The error is not represented by a path.
  1. Check the IMM2 system even log and the system-error log for information about the error.
  2. Save the log if necessary and clear the log afterwards.
System Error LED An error occurred.
  1. Check the light path LEDs and follow the listed instruction.
  2. Check the IMM2 system even log and the system-error log for information about the error.
  3. Save the log if necessary and clear the log afterwards.
OVER SPEC The power supplies are using more power than their maximum rating. The system is drawing power incoherent to power supply specified ratings.
If the OVER SPEC LED is lit, use one of the following procedures:
  1. Turn off the server, disconnect the power from the server.
  2. Remove the optical drive, fans, hard disk drives, and hard disk drive backplanes.
  3. Restart the server to see whether the problem remains.
  4. Reinstall each device that was removed in step 2 one at a time, starting the server each time, to isolate the failing device.
  5. Replace any failing device.
  6. (Trained technician only) Replace the system board.
LINK Reserved.  
PS A power supply is not detected or has failed.
  1. Check the power-supply in the server that has an lit yellow LED (see Power-supply LEDs).
  2. Make sure that the power supplies are seated correctly.
  3. Remove one of the power supplies to isolate the failed power supply.
  4. Replace the failed power supply.
PCI An error has occurred on a PCI card, a PCI bus or on the system board. An additional LED is lit on one of the riser cards.
  1. Check the system-event log for information about the error.
  2. Check the LEDs on the PCI riser cards to identify the component that caused the error.
  3. If you cannot isolate the failing adapter by using the LEDs and the information in the system-event log, remove one adapter at a time from the failing PCI bus; and restart the server after each adapter is removed.
  4. Replace the following components, in the order shown, restarting the server each time:
    • PCI riser card
    • (Trained technician only) Replace the system board.
FAN A fan has failed, is operating too slowly, or has been removed. The TEMP LED might also be lit.
  1. Check the LEDs on the server.
  2. Reseat the failing fan, which is indicated by a lit LED on the fan.
  3. Replace the failing fan.
TEMP The system temperature has exceeded a threshold level. A failing fan can cause the TEMP LED to be lit.
  1. Make sure that the air vents are not blocked.
  2. Determine whether a fan has failed. If it has, replace it.
  3. Make sure that the heat sink is seated correctly.
  4. Make sure that the room temperature is not too high. See Server features and specifications and System reliability guidelines for the server temperature information.
MEM An invalid memory configuration (both the MEM LED and CONFIG LED might be lit) or a memory error has occurred .
Note: Each time you install or remove a DIMM, you must disconnect the server from the power source; then, wait 10 seconds before restarting the server.
  1. If the MEM LED and the CONFIG LED are lit, the system issues an invalid memory configuration error. Complete the following steps to correct the problem:
    1. Check the system-event log in the Setup utility or IMM error messages. Follow steps indicated in UEFI (POST) error codes and Integrated Management Module II (IMM2) error messages.
  2. If the CONFIG LED is not lit, the system has detected a memory error. Complete the following steps to correct the problem:
    1. Update the firmware to the latest level (see Updating the firmware).
    2. Reseat or swap the DIMMs.
    3. Check the system-event log in the Setup utility or IMM error messages. Follow steps indicated in UEFI (POST) error codes and Integrated Management Module II (IMM2) error messages.
NMI A nonmaskable interrupt has occurred, or the NMI button was pressed. Check the system-event log for information about the error.
CONFIG A hardware configuration error has occurred.
  1. If the CONFIG LED and the CPU LED are lit, complete the following steps to correct the problem:
    1. Check the microprocessors that were just installed to make sure that they are compatible with each other (see Replacing a microprocessor and heat sink for additional information about microprocessor requirements).
    2. (Trained technician only) Replace the incompatible microprocessor.
    3. Check the system-event logs for information about the error. Replace any components that are identified in the error log.
  2. If the CONFIG LED and the MEM LED are both lit, complete the following steps:
    1. Make sure that the DIMM configuration is supported (see Installing a memory module for DIMM requirements and installation sequence information).
    2. Replace the DIMMs with a supported configuration.
CPU An invalid microprocessor configuration or a microprocessor has failed (both the CPU LED and the CONFIG LED might be lit).
  1. If the CONFIG LED is lit, the system issues an invalid microprocessor configuration error. Complete the following steps to correct the problem:
    1. Check the microprocessors that were just installed to make sure that they are compatible with each other (see Replacing a microprocessor and heat sink for additional information about microprocessor requirements) and use the Setup utility and select System Information → System Summary → Processor to verify the microprocessors information.
    2. (Trained technician only) Replace the incompatible microprocessor.
    3. Check the system-event logs for information about the error. Replace any components that are identified in the error log.
  2. If the CPU LED is lit and the CONFIG LED is not lit, complete the following steps:
    1. (Trained technician only) Make sure that the failing microprocessor, which is indicated by a lit LED on the system board, is installed correctly. See Replacing a microprocessor and heat sink for information about installation and requirements.
When only the CPU LED is lit, a microprocessor has failed. If the CONFIG LED is not lit, a microprocessor failure occurs, complete the following steps to correct the problem:
  1. (Trained technician only) Make sure that the failing microprocessor and its heat sink, which are indicated by a lit LED on the system board, are installed correctly. See Replacing a microprocessor and heat sink for information about installation and requirements.
  2. (Trained technician only) Replace the failing microprocessor (see Removing a microprocessor and heat sink and Replacing a microprocessor and heat sink).
  3. For more information, go to the IBM Service website.
HDD A hard disk drive has failed or is missing.
  1. Check the LEDs on the hard disk drives for the drive with a lit status LED and reseat the hard disk drive.
  2. Make sure that the cables are correctly connected to the hard disk drive backplane.
  3. For more information, see Hard disk drive problems.
  4. If the error remains, replace the following components in the order listed, restarting the server after each:
    1. Replace the hard disk drive.
    2. Replace the hard disk drive backplane.
  5. If the error remains, replace the following components one at a time, in the order listed, restarting the server after each:
    1. Replace the hard disk drive.
    2. Replace the hard disk drive backplane.
  6. If the problem remains, go to the IBM Service website.
BOARD An error has occurred on the system board.
  1. Check the LEDs on the server.
  2. Check the LEDs on the system board to identify the component that caused the error. The BOARD LED can be lit due to any of the following reasons:
    • Battery
    • Missing PCI riser-card assembly
    • Failed firmware update
    • Failed system board
  3. Check the system-event log for information about the error.
  4. Replace any failed or missing replacement components, such as the battery or PCI riser-card assembly.
  5. (Trained technician only) replace the server system board.
Parent topic: Light path diagnostics