Mitsubishi A1SJH(S8) User Manual page 63

4. CPU MODULE
REMARK
(1) As to the LED indication, the order of priority of the LED indication can
be changed if CPU module is in the operation mode. (Error codes are
stored in the special register.)
(2) When the special relay M9084 is ON, checking on fuse blown, I/O
verification and the battery are not performed. (Error codes are not
stored in the special register.)
(3) The "Error indication of peripheral device" in the table of self-diagnostics
functions are messages that is indicated by the PLC diagnosis of
peripheral devices.
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