Chapter 4 81
Intermittent Problems
Intermittent system hang problems can be caused by a variety of reasons that have nothing to do with a
hardware defect, such as: cosmic radiation, electrostatic discharge, or software errors. FRU replacement
should be considered only when a recurring problem exists.
When analyzing an intermittent problem, do the following:
1. Run the diagnostic test for several times to isolate the problem.
2. If no error is detected, do not replace any FRU.
3. If any error is detected, replace the FRU. Rerun the test to verify that there are no more errors.
If an error is detected by the main battery test, see “Check the Power Adapter” on page 72
If an error is detected by the display test, see “Index of Symptom-to-FRU Error Message” on page
78 .
If an error is detected by the floppy disk drive test, see “External Diskette Drive Check” on page 70.
If an error is detected by the keyboard test, see “Keyboard or Auxiliary Input Device Check” on
page 71.