Omron · CJ-series CJ2 CPU Unit
An error has occurred in the communication bus line between the CPU and I/O Units, or the End Cover is not correctly connected to the CPU Rack or an Expansion Rack. This is a fatal error, indicated by flag A401.14. Auxiliary Area A404 contains the error slot number (00 to 09, with '0F hex' for undetermined slot, '0B hex' for built-in EtherNet/IP port bus error) and rack number (00 to 03, with '0E hex' for missing End Cover).
Click steps to track your progress.
Cycle power OFF and ON again to the PLC system.
If the error persists, turn power OFF and physically check all cable connections between I/O Units and Racks, and verify End Covers are securely connected.
Inspect I/O bus cables and I/O Units for any signs of physical damage.
Cycle power OFF and ON again to the Rack's power supply.