Mitsubishi MELSEC L Series User Manual page 86

(2) LED indication status
Checkbox
When an LED indication error is detected, perform troubleshooting according to the error location.
CPU module
Power supply module, I/O module
84
Is the MODE LED of the CPU module lit green?
Is the RUN LED of the CPU module lit green?
Is the ERR. LED of the CPU module off?
Is the USER LED of the CPU module off?
Is the BAT. LED of the CPU module off?
Is the I/O ERR. LED of the CPU module off?
When an input signal is on, are all the corresponding LEDs on?
When an output signal is on, are all the corresponding LEDs on?
Is the RUN LED for CC-Link lit green?
Is the ERR. LED for CC-Link off?
Is the L RUN LED for CC-Link lit green?
Is the L ERR. LED for CC-Link off?
Is the POWER LED of the power supply module lit green?
Are the indicators of the input module correctly lit when the input signal is on?
Are the indicators of the output module correctly lit when the output signal is on?
Error location
CPU (MODE, RUN, ERR., USER, and BAT.)
Built-in function (I/O ERR., X0 to XF, and Y0 to Y7)
CC-Link (RUN, ERR., L RUN, and L ERR.)
Reference
Page 90, CHAPTER 15
MELSEC-L CC-Link System Master/Local
Module User's Manual
Page 90, CHAPTER 15