Troubleshooting Flowcharts
Section 5-2
5-2 Troubleshooting Flowcharts
Main Flowchart
When an unknown error arises, the following troubleshooting flowchart can be
used to help locate the problem.
Main flowchart
NO
NO
YES
NO
NO
POWER indicator lit?
See Power Check Flowchart
See Fault Check Flowchart
See Error Check Flowchart
See I/O Check Flowchart
YES
RUN indicator lit?
YES
ALARM indicator
lit?
NO
I/O sequence
correct?
YES
Environment normal?
See Environment Check Flowchart
YES
Replace Unit
Note 1. Before replacing a Unit, be sure to turn off the power to the PC. The same
applies to when replacing the Expansion Data Memory Unit, batteries, wir
-
ing, and cables.
2. When replacing the CPU, start operation only after transferring the contents
of the data memory or holding bits that are required for resuming operation
to the replaced CPU.
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