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FANUC Alarm FXTL-035Unmatched BUILD_BEGIN or loop

FANUC FXTL-035 (“Unmatched BUILD_BEGIN or loop”): A BUILD_BEGIN did not have a BUILD_END, a LOOP_BEGIN did not have a LOOP_END, or there was some other error in matching looping statements. First check: Correct the model files and copy them to the controller.

Updated 2026-08-29 · LogrobotLM reference

Description

A BUILD_BEGIN did not have a BUILD_END, a LOOP_BEGIN did not have a LOOP_END, or there was some other error in matching looping statements.

Remedy · Remède

Correct the model files and copy them to the controller.

Frequently asked · Questions fréquentes

What does FANUC alarm FXTL-035 mean?
FANUC FXTL-035 (“Unmatched BUILD_BEGIN or loop”): A BUILD_BEGIN did not have a BUILD_END, a LOOP_BEGIN did not have a LOOP_END, or there was some other error in matching looping statements.
How do you troubleshoot FANUC alarm FXTL-035?
Correct the model files and copy them to the controller.

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 →