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Light path diagnostics LEDs

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 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 IMM2 event log or the system-event log for additional information before you replace a FRU.
Table 1. Light path diagnostics panel LEDs.

A table with one spanned column at the top and three additional columns with headers. This table provides information about symptoms and user actions to solve light path diagnostic LED problems.

  • Follow the suggested actions in the order in which they are listed in the Action column until the problem is solved.
  • See Parts listing, Lenovo System x3750 M4 Type 8753 to determine which components are customer replaceable units (CRU) and which components are field replaceable units (FRU).
  • If a action step is preceded by (Trained service technician only), that step must be performed only by a trained service technician.
LEDDescriptionAction
None, but the system error LED is lit.An error has occurred and cannot be isolated. The error is not represented by a path.Use the Setup utility to check the system event log for information about the error (see Using the Setup utility).
PSA power supply 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.
OVER SPECThe server is using more power than the power supplies can output.
  1. Install an additional power supply or change the input power source from 110 V to 220 V.
  2. Remove any recently installed options.
  3. Restart the server to see whether the problem remains.
PCIAn error has occurred on a PCI bus on the system board or on the PCI riser-card. An additional LED might be lit on one of the PCI slots on the system board or the riser-card.
  1. Check the IMM2 event log for information about the error.
  2. Check the LEDs on the system board or PCI riser-card 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 IMM2 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 service technician only) Replace the system board.
NMIA nonmaskable interrupt has occurred.Check the IMM2 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 step 1 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 service technician only) Replace the incompatible microprocessor.
    3. Check the IMM2 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.
LINKReserved. 
CPUAn 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. See CONFIG LED action plan for more information.
  2. If the CPU LED is lit and the CONFIG LED is not lit, complete the following steps:
    1. (Trained service technician only) Make sure that the failing microprocessor, which is indicated by a lit LED on the system board or microprocessor and memory expansion tray, is installed correctly. See Replacing a microprocessor and heat sink for more information.
    2. If there is no microprocessor and memory expansion tray installed, remove the DIMM air baffle and check the LEDs on the system board to see which microprocessor LED is lit, then do the following:
      1. Check the IMM2 event logs for information about the error. Replace any components that are identified in the error log.
      2. (Trained service technician only) Replace the microprocessor.
    3. If the microprocessor and memory expansion tray is installed, do the following:
      1. Check the LEDs on the microprocessor and memory expansion tray. If one of the microprocessor LEDs is lit, do the following:
        1. (Trained service technician only) Replace the microprocessor.
      2. If the System board error LED is lit on the microprocessor and memory expansion tray, do the following:
        1. Turn off the server. Remove the top cover and the microprocessor and memory expansion tray; then, press the light path button on the system board to light the LEDs associated with the failed microprocessor (See System-board LEDs for the location of the light path button).
        2. (Trained service technician only) Replace the failing microprocessor, which is indicated by the lit LED on the system board.
MEMAn invalid memory configuration (both the MEM LED and CONFIG LED might be lit) or a memory error has occurred.
  1. If the MEM LED and the CONFIG LED are lit, the system issues an invalid memory configuration error. See the CONFIG LED action plan for more information.
  2. If the CONFIG LED is not lit, the system has detected a memory error. Complete the following steps to correct the problem:
    1. Turn off the server.
    2. Remove the top cover and press the light path button on the system board to light the LEDs (See System-board LEDs for the location of the light path button).
    3. Check the LEDs on the server and the microprocessor and memory expansion tray.
    4. If there is no microprocessor and memory expansion tray installed, remove the DIMM air baffle and check the LEDs on the system board to see which DIMM LED is lit, then do the following:
      1. Make sure that DIMM is seated correctly.
      2. Replace the DIMM.
    5. If the microprocessor and memory expansion tray is installed, do the following:
      1. Check the LEDs on the microprocessor and memory expansion tray. If one of the DIMM LEDs is lit, do the following:
        1. Make sure that DIMM is seated correctly.
        2. Replace the DIMM.
      2. If the System board error LED is lit on the microprocessor and memory expansion tray, do the following:
        1. Turn off the server and disconnect it from the power source. Remove the top cover and the microprocessor and memory expansion tray; then, press the light path button on the system board to light the LEDs associated with the failed DIMM (See System-board LEDs for the location of the light path button).
        2. Make sure that all DIMMs are seated correctly.
        3. Replace the failing DIMM, which is indicated by the lit DIMM latch on the system board (the DIMM LED is underneath the DIMM latch).
TEMPThe 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. Make sure that all fans are seated correctly.
  3. Determine whether a fan has failed (indicated by a lit LED on the fan). If it has, replace the fan.
  4. Make sure that the heat sink is seated correctly.
  5. Make sure that the room temperature is not too high. See Server features and specifications and Installation guidelines for the server temperature information.
FANA fan has failed, is operating too slowly, or has been removed. The TEMP LED might also be lit.
  1. Check the LEDs on the hot-swap fan.
  2. Reseat the failing fan, which is indicated by a lit LED on the fan.
  3. Replace the failing fan.
BOARDAn 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 many reasons, for example:
    • RAID cache card
    • Battery
    • Failed system board
  3. Check the IMM2 event log for information about the error.
  4. Replace any failed or missing replacement components, such as the battery.
  5. (Trained service technician only) replace the server system board.
HDDA 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.