LogrobotLM

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FANUC Alarm SYST-121 — WARN No decision input group defined

FANUC SYST-121 (“WARN No decision input group defined”): The decision code input group, which is required with the current program selection options, has not been defined. First check: Set up a decision code input group in the Cell Input I/O and Group I/O menus and restart the robot.

Updated 2026-09-17 · LogrobotLM reference

Description

The decision code input group, which is required with the current program selection options, has not been defined.

Remedy

Set up a decision code input group in the Cell Input I/O and Group I/O menus and restart the robot.

Related codes

SYST-119WARN No echo strobe output definedSYST-120WARN No style option input definedSYST-122WARN No style output group definedSYST-123WARN No option output defined

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 →