LogrobotLM

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FANUC Alarm PRIO-490 — Modbus TCP Server Error

FANUC PRIO-490 (“Modbus TCP Server Error”): The Modbus TCP Server running on the robot is enabled and has an error. First check: Alarm severity and last state behavior can be modified using the Modbus TCP Slave configuration screen.

Updated 2026-09-17 · LogrobotLM reference

Description

The Modbus TCP Server running on the robot is enabled and has an error. Refer to additional cause code text for further details.

Remedy

Alarm severity and last state behavior can be modified using the Modbus TCP Slave configuration screen. Refer to the Modbus Setup and Operations Manual for more information.

Related codes

PRIO-360EtherNet/IP Adp Not in Run ModePRIO-369EtherNet/IP System ErrorPRIO-493Modbus Socket ErrorPRIO-494Modbus Active Close

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 →