Serial Port Problems - Lenovo ThinkServer RD120 Installation Manual

v Follow the suggested actions in the order in which they are listed in the Action column until the problem
is solved.
v See the parts listing in the Hardware Maintenance Manual to determine which components are customer
replaceable units (CRU) and which components are field replaceable units (FRU).
v If an action step is preceded by "(Trained service technician only)," that step must be performed only by a
trained service technician.
Symptom
The server does not turn off.
The OVER SPEC LED on the
Easy LED Diagnostics panel is
lit, and the one of the power
channel LEDs on the system
board is lit.
The server unexpectedly shuts
down, and the LEDs on the
operator information panel are
not lit.

Serial port problems

v Follow the suggested actions in the order in which they are listed in the Action column until the problem
is solved.
v See the parts listing in the Hardware Maintenance Manual to determine which components are customer
replaceable units (CRU) and which components are field replaceable units (FRU).
v If an action step is preceded by "(Trained service technician only)," that step must be performed only by a
trained service technician.
Symptom
The number of serial ports that
are identified by the operating
system is less than the number
of installed serial ports.
Action
1. Turn off the server by pressing the power-control button for 5 seconds.
2. Restart the server.
3. If the server fails POST and the power-control button does not work, disconnect
the power cord for 20 seconds; then, reconnect the power cord and restart the
server.
Attention: In a dc power environment, only trained service personnel other
than Lenovo service technicians are authorized to connect or disconnect power
to the dc power supply. See the documentation that comes with each dc power
supply.
4. If the problem remains, suspect the system board.
See the power troubleshooting table in the Hardware Maintenance Manual or call
for service.
See "Solving undetermined problems" in the Hardware Maintenance Manual.
Action
1. Make sure that:
v Each port is assigned a unique address in the Configuration/Setup Utility
program and none of the serial ports is disabled.
v The serial-port adapter (if one is present) is seated correctly.
2. Reseat the serial port adapter, if one is present.
3. Replace the serial port adapter, if one is present.
Chapter 5. Solving problems
61