Lenovo System x3550 M4 Installation And Service Manual page 141

Table 14. Light path diagnostics panel LEDs (continued)
• Follow the suggested actions in the order in which they are listed in the Action column until the problem is
solved.
• If an action step is preceded by "(trained technician only)," that step must be performed only by a trained
technician.
Description
LED
CPU When only the CPU LED is lit, a
microprocessor has failed.
CPU + CONFIG When both the
CPU LED and the CONFIG LED
are lit, the microprocessor
configuration is invalid.
MEM When only the MEM LED is lit, a
memory error has occurred.
Action
If the CONFIG LED is not lit, a microprocessor failure occurs,
complete the following steps:
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" on page 288
for information about installation and requirements.
2. (Trained technician only) Replace the failing
microprocessor (see "Removing a microprocessor and
heat sink" on page 283 and "Replacing a microprocessor
and heat sink" on page 288).
3. For more information, go to
entry/portal/docdisplay? lndocid=SERV-CALL
If the CONFIG LED and the CPU LED are 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" on page 288
for additional information about microprocessor
requirements).
2. (Trained technician only) Replace the incompatible
microprocessor.
3. Check the system-error logs for information about the
error. Replace any component that is identified in the error
log.
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.
If the CONFIG LED is not lit, the system might detect a memory
error. Complete the following steps to correct the problem:
1. Update the server firmware to the latest level (see
"Updating the firmware" on page 91).
2. Reseat or swap the DIMMs with lit LED.
3. Check the system-event log in the Setup utility or IMM
error messages. Follow steps indicated in Appendix B
"UEFI/POST diagnostic codes" on page 715 and Appendix
A "Integrated management module II (IMM2) error
messages" on page 305.
4. Replace the failing DIMM (see "Removing a memory
module" on page 216 and "Installing a memory module"
on page 45).
http://www.ibm.com/support/
.
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Chapter 4 Troubleshooting
127