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

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Chapter 5. Diagnostics
This chapter describes the diagnostic tools that are available to help you solve
problems that might occur in the server.
If you cannot locate and correct the problem using the information in this chapter,
see Appendix A, “Getting help and technical assistance,” on page 169 for more
information.
Diagnostic tools
The following tools are available to help you diagnose and solve hardware-related
problems:
v
POST beep codes, error messages, and error logs
The power-on self-test (POST) generates beep codes and messages to indicate
successful test completion or the detection of a problem. See “POST” for more
information.
v Troubleshooting tables
These tables list problem symptoms and actions to correct the problems. See
“Troubleshooting tables” on page 123.
v Light path diagnostics
Use the light path diagnostics to diagnose system errors quickly. See “Light path
diagnostics” on page 136 for more information.
v
Diagnostic programs, messages, and error messages
The diagnostic programs, which are stored in upgradeable read-only memory
(ROM) on the system board, are the primary method of testing the major
components of the server. See “Diagnostic programs, messages, and error
codes” on page 141 for more information.
POST
When you turn on the server, it performs a series of tests to check the operation of
the server components and some optional devices in the server. This series of tests
is called the power-on self-test, or POST.
If a power-on password is set, you must type the password and press Enter, when
prompted, for POST to run.
If POST detects a problem, one or more beeps might sound, or an error message
is displayed. See “POST beep codes” and “POST error codes” on page 108 for
more information.
POST beep codes
A beep code is a combination of short or long beeps or a series of short beeps that
are separated by pauses. For example, a “1-2-3” beep code is one short beep, a
pause, two short beeps, and pause, and three short beeps. A beep code indicates
that POST has detected a problem.
A single problem might cause more than one error message. When this occurs,
correct the cause of the first error message. The other error messages usually will
not occur the next time POST runs.
© Copyright IBM Corp. 2006, 2007
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