Solving Power Problems - Lenovo ThinkServer RD120 Hardware Maintenance 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 Chapter 3, "Parts listing, ThinkServer RD120 Machine Types 6444, 6445, 6446, and 6447," on page 25
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.
System event/error log message
CPU n non-critical over temperature warning
n = the microprocessor number
CPU n non-recoverable over temperature fault
VRD 1 critical over voltage fault
VRD 1 critical under voltage fault
VRD 2 critical over voltage fault
VRD 2 = VRM
VRD 2 critical under voltage fault
VRD 2 = VRM
Processor VTT Power Fault.

Solving power problems

Attention:
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.
Power problems can be difficult to solve. For example, a short circuit can exist
anywhere on any of the power distribution buses. Usually, a short circuit will cause
the power subsystem to shut down because of an overcurrent condition. To
diagnose a power problem, use the following general procedure:
1. Turn off the server and disconnect all power cords.
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ThinkServer RD120 server Machine Types 6444, 6445, 6446, and 6447: Hardware Maintenance Manual
Action
1. Make sure that the fans are operating, that there are no
obstructions to the airflow, that the air baffles are in place and
correctly installed, and that the server cover is installed and
completely closed.
2. Make sure that the heat sink for microprocessor n is installed
correctly.
1. Make sure that the fans are operating, that there are no
obstructions to the airflow, that the air baffles are in place and
correctly installed, and that the server cover is installed and
completely closed.
2. Make sure that the heat sink for microprocessor n is installed
correctly.
3. (Trained service technician only) Replace microprocessor n
4. (Trained service technician only) Replace the system board.
1. (Trained service technician only) Reseat microprocessor 1.
2. (Trained service technician only) Replace the system board.
1. (Trained service technician only) Reseat microprocessor 1.
2. (Trained service technician only) Replace the system board.
1. Reseat the VRM.
2. (Trained service technician only) Reseat microprocessor 2.
3. (Trained service technician only) Replace the system board.
1. Reseat the VRM.
2. (Trained service technician only) Reseat microprocessor 2.
3. (Trained service technician only) Replace the system board.
1. (Trained service technician only) Reseat microprocessor 1.
2. (Trained service technician only) Replace the system board.
In a dc power environment, only trained service personnel other than