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FANUC Alarm ARC-056Invalid sync (%s^4,%d^5)

FANUC ARC-056 (“Invalid sync (%s^4,%d^5)”): An Arc Start instruction specified synchronizing with an Equipment that is not also synchronized. First check: Check the synchronization equipment number specified in the Arc instruction or in the specified weld schedule SYNCDT detail menu.

Updated 2026-08-29 · LogrobotLM reference

Description

An Arc Start instruction specified synchronizing with an Equipment that is not also synchronized.

Remedy · Remède

Check the synchronization equipment number specified in the Arc instruction or in the specified weld schedule SYNCDT detail menu. Refer to the Arc Start Synchronization section in the FANUC ArcTool Operator's Manual.

Frequently asked · Questions fréquentes

What does FANUC alarm ARC-056 mean?
FANUC ARC-056 (“Invalid sync (%s^4,%d^5)”): An Arc Start instruction specified synchronizing with an Equipment that is not also synchronized.
How do you troubleshoot FANUC alarm ARC-056?
Check the synchronization equipment number specified in the Arc instruction or in the specified weld schedule SYNCDT detail menu. Refer to the Arc Start Synchronization section in the FANUC ArcTool Operator's Manual.

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 →