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FANUC Alarm HOST-143WARN Comm port cannot be closed

FANUC HOST-143 (“WARN Comm port cannot be closed”): The selected hardware port defined for the Comm Tag could not be closed. First check: Power the controller OFF and then ON and try again.

Updated 2026-08-29 · LogrobotLM reference

Description

The selected hardware port defined for the Comm Tag could not be closed.

Remedy · Remède

Power the controller OFF and then ON and try again. If the error occurs again a cabling or hardware problem might exist with the port.

Frequently asked · Questions fréquentes

What does FANUC alarm HOST-143 mean?
FANUC HOST-143 (“WARN Comm port cannot be closed”): The selected hardware port defined for the Comm Tag could not be closed.
How do you troubleshoot FANUC alarm HOST-143?
Power the controller OFF and then ON and try again. If the error occurs again a cabling or hardware problem might exist with the port.

Related codes / Codes liés

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 →