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FANUC Alarm SRVO-239SERVO Chain 2 (SVON) abnormal

FANUC SRVO-239 (“SERVO Chain 2 (SVON) abnormal”): A single chain 2 (0V) failure occurred when a SVON (Servo ON/OFF switch) input was asserted. First check: Repair the circuit of the chain 2 (0V) on SVON the hardware.

Updated 2026-08-29 · LogrobotLM reference

Description

A single chain 2 (0V) failure occurred when a SVON (Servo ON/OFF switch) input was asserted.

Remedy · Remède

Repair the circuit of the chain 2 (0V) on SVON the hardware. Set CHAIN FAILURE detection to TRUE on the SYSTEM/CONFIG screen. Press RESET on the teach pendant.

Frequently asked · Questions fréquentes

What does FANUC alarm SRVO-239 mean?
FANUC SRVO-239 (“SERVO Chain 2 (SVON) abnormal”): A single chain 2 (0V) failure occurred when a SVON (Servo ON/OFF switch) input was asserted.
How do you troubleshoot FANUC alarm SRVO-239?
Repair the circuit of the chain 2 (0V) on SVON the hardware. Set CHAIN FAILURE detection to TRUE on the SYSTEM/CONFIG screen. Press RESET on the teach pendant.

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 →