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FANUC Alarm PRIO-621 — PNIO(D) device is not running

FANUC PRIO-621 (“PNIO(D) device is not running”): The start up of I/O Device has not completed or was terminated by an error. First check: "Disable the I/O Device if the I/O Device function is not used.

Updated 2026-09-17 · LogrobotLM reference

Description

The start up of I/O Device has not completed or was terminated by an error.

Remedy

"Disable the I/O Device if the I/O Device function is not used. If the I/O Device function is used, check if there are any error related to the I/O Device. Check if I/O Controller used to communicate with the robot controller is running. This error will be eliminated when the setting of the I/O Device is correct and communication to the I/O Controller is established.

Related codes

PRIO-619PNIO(C) mismatch st … slot … …PRIO-620PNIO(C) station … deactivatedPRIO-622PNIO(C) controller is not runningPRIO-623PNIO(C) not in operation mode

Indicative field information — the robot manufacturer's manual and safety procedures always prevail. Never bypass a safety device; apply lockout/tagout (LOTO) before any physical intervention. How this reference is built →