Mitsubishi Electric · MELSEC System Q/L Series
This fault signifies a failure in the initial communication process between CPU modules in a multiple CPU system. It is triggered by a lack of response from a target CPU module or the presence of an incompatible CPU module within the system. The error occurs at power ON or reset, causing the multiple CPU system to stop.
Click steps to track your progress.
Reset the CPU module and attempt to transition it to RUN mode again.
Remove any CPU module identified as incompatible with the multiple CPU system from the main base unit.
Replace any CPU module incompatible with the multiple CPU system with a compatible one.
Verify all communication cabling between CPU modules for proper connection and integrity.