After Second Attempt - NCR PC4i Service Manual

BASIC TROUBLESHOOTING
b. If any other errors are indicated, go to step 2.
c. If the computer has been reconfigured for the
purpose of troubleshooting, it is necessary to
restore the machine step by step to full
configuration, retesting at each incremental
buildup to determine whether the addition of any
specific component causes any malfunction.
d. The computer has been reconfigured if any of the
following steps were performed:
1. Configuration switch settings were changed as
a result of the check in step 6 of "After the
First Attempt".
2. Expansion adapter boards were removed in step
2 "After Second Attempt".
3. Parallel or serial port devices were
disconnected in step 3 of After Second
Attempt.
4. Configuration switches were changed to
restrict the memory test to the minimum 256KB
in step 5 of "After Second Attempt".
e. If the computer was reconfigured, and has not
yet been restored and retested at full
configuration, go to step 1 in the Restore Full
Configuration section.
f. If the computer was not reconfigured, or has been
restored step by step to full configuration and
retested, go to step 3.
2. If the message
•Interrupt Failure•
is
displayed, a MPB failure is indicated. See (
"Service Diagnostics" to continue diagnosing
the condition.
3. If the message Error in
•Expansion Memory•
is
displayed on the screen, hardware parity must
be checked by removing the expansion memory
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