11 TROUBLESHOOTING

11.2.3 Flowchart for when the "MODE" LED is flickering

MELSEC-Q

The following shows the flowchart to be followed when the "MODE" LED of the CPU module flickers at PLC power-on, at operation start or during operation.

"MODE" LED is flickering

Did you make forced

YES

 

 

 

 

 

 

 

 

 

 

Cancel forced ON/OFF.

 

 

 

 

 

ON/OFF setting?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

NO

NO

 

 

YES

 

Is the "MODE" LED turned on?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Is the RESET/L.CLR

RESET position

 

 

 

 

 

 

 

 

Move the RESET/L.CLR switch to the

 

 

switch of the CPU module in

 

 

 

 

 

 

the neutral position?

 

 

 

 

neutral position.

 

 

 

Neutral position

NO

 

 

YES

 

Is the "MODE" LED turned on?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Hardware fault

Check operations in the order

starting from the minimum system.Completion If the module will not work,

please consult your local Mitsubishi service center or representative, explaining a detailed description of the problem.

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