LogrobotLM

LogrobotLM — AI fault diagnosis for ABB · KUKA · FANUC robots. It reads your robot backup in your browser (never uploaded) and pinpoints the fault. Try it free → · Le diagnostic IA qui lit la sauvegarde de votre robot, sans rien téléverser.

FANUC Alarm PRIO-021 — SYST Unknown I/O hardware

FANUC PRIO-021 (“SYST Unknown I/O hardware”): An unknown device is connected to the I/O Link connector. First check: Replace the device with a device that is compatible with the current software or install a version of software that recognizes the device.

Updated 2026-08-29 · LogrobotLM reference

Description

An unknown device is connected to the I/O Link connector. This device is not recognized by the current controller software version.

Remedy · Remède

Replace the device with a device that is compatible with the current software or install a version of software that recognizes the device.

Frequently asked · Questions fréquentes

What does FANUC alarm PRIO-021 mean?
FANUC PRIO-021 (“SYST Unknown I/O hardware”): An unknown device is connected to the I/O Link connector. This device is not recognized by the current controller software version.
How do you troubleshoot FANUC alarm PRIO-021?
Replace the device with a device that is compatible with the current software or install a version of software that recognizes the device.

Related codes / Codes liés

PRIO-017WARN I/O point not simulatedPRIO-020STOP I/O Link comm error %x, %x, %x, %x (hex)PRIO-022SYST Too much I/O data on I/O linkPRIO-023WARN No ports of this type

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. · Informations indicatives issues du terrain — le manuel du constructeur et ses procédures de sécurité font foi. Ne shuntez jamais un organe de sécurité ; consignez (LOTO) avant toute intervention physique. How this reference is built →