Omron · CJ-series CJ2 CPU Unit
Writing to the built-in flash memory failed, indicated by A315.15. This non-fatal error means that critical backup data may not have been correctly saved, and proper operation may not be possible the next time power is restored after a power interruption due to loss of retained data.
Click steps to track your progress.
Replace the CPU Unit, as the built-in flash memory is likely faulty.