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6   INSPECTION AND MAINTENANCE 
 
(o)   When "RUN" LED is flickering 
If the "RUN" LED flickers, follow the steps below. 
When the programs or parameters are written into the Motion controller 
during STOP status and then the RUN/STOP/RESET switch is set from 
STOP to RUN, the RUN LED flickers. 
Although this status does not mean the Motion controller error, the Motion 
controller stops the operation. To set the Motion controller into RUN status, 
reset the Motion controller using the RUN/STOP/RESET switch or set the 
RUN/STOP/RESET switch from STOP to RUN again. 
With this setting, the RUN LED turns on. 
 
(p)   Flowchart for when "ERR." LED turns on/is flickering 
The following shows the flowchart for when "ERR." LED turns on or flickers 
at Motion controller’s power-on, at operation start or during operation. 
 
"ERR." LED turns on or is flickering.
NO
YES
A hardware fault
Explain the error symptom and get 
advice from our sales representative.
Hardware cause fault?
Set the RUN/STOP/RESET switch to
STOP.
Reset the Motion controller.
Set the RUN/STOP/RESET switch to
RUN.
YES
NO
Does "ERR." LED turn off?
END
Confirm details of error by
PC diagnostics of GX Works2.
Correct error contents while referring 
to the help of the GX Works2.