IBM System x3750 M4 Installation And Service Manual page 195

Table 23. Light path diagnostics panel LEDs (continued)
v Follow the suggested actions in the order in which they are listed in the Action column until the problem is
solved.
v See Chapter 3, "Parts listing", to determine which components are customer replaceable units (CRU) and
which components are field replaceable units (FRU).
v If a action step is preceded by (Trained service technician only), that step must be performed only by a trained
service technician.
LED Description
MEM An invalid memory
configuration (both the MEM
LED and CONFIG LED
might be lit) or a memory
error has occurred .
Action
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 on page 1 on page 175 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:
a. Turn off the server.
b. Remove the top cover and press the light path button on the
system board to light the LEDs (See "System-board LEDs" on
page 33 for the location of the light path button).
c. Check the LEDs on the server and the microprocessor and
memory expansion tray.
d. 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.
e. 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:
a) Make sure that DIMM is seated correctly.
b) Replace the DIMM.
2) If the System board error LED is lit on the microprocessor
and memory expansion tray, do the following:
a) 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" on page 33 for the location of the light path
button).
b) Make sure that all DIMMs are seated correctly.
c) Replace the failing DIMM, which is indicated by the lit
DIMM latch on the system board (the DIMM LED is
underneath the DIMM latch).
Chapter 4. Troubleshooting
177