251

Invalid Input Data 2

Fanuc · Alpha i series AC Servo Motor

What does 251 mean?

Input data 2 specified with a function code is invalid. This indicates an issue with the format or value of the second input data.

Common Causes

  • Invalid input data 2 specified via a function code.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Check the input data 2 value specified with a function code.

Browse all codes in this manual (60)
Verified technical data. Last updated: March 2026

Related Faults

Source: Fanuc Alpha i series AC Servo Motor