IBM 5150 Hardware Maintenance Manual page 66

You have gone through the PICs without resolving your
problem. The following steps should help you to find
additional
audio
or
visual
symptoms.
1. Check the entire system for loose or damaged connectors.
2. Review PIC 010, "Start."
3. Select "Utilities" in the diagnostic menu, start an error
log, and select "Run tests multiple times." This will allow
you to exercise the machine thoroughly and identify the
failing symptom. When you have identified the symptom,
go to PIC 010 "Start" or the appropriate PIC for that
symptom.
If you have followed these procedures and still have an
unresolved problem, you should seek technical assistance.
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