254

Invalid Function Code or Mode

Fanuc · Alpha i series AC Servo Motor

What does 254 mean?

An invalid function code or mode has been specified, preventing the system from performing the requested operation. This could be due to an incorrect command or an unsuitable operating mode.

Common Causes

  • Invalid function code specified.
  • Invalid operating mode selected.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Check the command code specified with a function code.

  2. 2

    Verify the currently selected operating mode.

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

Related Faults

090Reference Position Setting Error404Regenerative Discharge Unit Overheat405Reference Position Return Error
Source: Fanuc Alpha i series AC Servo Motor
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