IBM x3550 - System - 7978, Problem Determination And Service Manual

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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, Type 7978 and 1913 server,” on page 29 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 Action
CPU n non-critical over temperature warning
n = the microprocessor number
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. (Trained service technician only) Make sure that the heat sink
for microprocessor n is installed correctly.
CPU n non-recoverable over temperature fault
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. (Trained service technician only) 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.
VRD 1 critical over voltage fault
1. (Trained service technician only) Reseat microprocessor 1.
2. (Trained service technician only) Replace the system board.
VRD 1 critical under voltage fault
1. (Trained service technician only) Reseat microprocessor 1.
2. (Trained service technician only) Replace the system board.
VRD 2 critical over voltage fault
1. (Trained service technician only) Reseat microprocessor 2.
2. (Trained service technician only) Replace the system board.
VRD 2 critical under voltage fault
1. (Trained service technician only) Reseat microprocessor 2.
2. (Trained service technician only) Replace the system board.
Microprocessor VTT Power Fault.
1. (Trained service technician only) Reseat microprocessor 1.
2. (Trained service technician only) Replace the system board.
Bus Uncorrectable Error (BUE). This error can be cause by a defective adapter, DIMM, or
microprocessor. Check the BMC log or system-error log for
additional errors (see “Error logs” on page 107).
Solving power problems
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 ac power cords.
2. Check the power-fault LEDs on the system board. See (“Power problems” on
page 132).
3. Check for loose cables in the power subsystem. Also check for short circuits, for
example, if a loose screw is causing a short circuit on a circuit board.
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IBM System x3550 Type 7978 and 1913: Problem Determination and Service Guide