FANUC Alarm MARL-038 — WARN … Invalid field value
Manufacturer wording — WARN %s Invalid field value
The manual prints placeholders; your controller fills them in with the real group, axis or number.
FANUC MARL-038 (“WARN … Invalid field value”): This indicates that there is a problem with the serial line used for the active gripper device. First check: You must clear the serial line by changing it in the PORT I/O menu from No Use to Host Comm and then back to No Use.
Updated 2026-09-17 · LogrobotLM reference
Description
This indicates that there is a problem with the serial line used for the active gripper device.
Remedy
You must clear the serial line by changing it in the PORT I/O menu from No Use to Host Comm and then back to No Use. Follow these steps:
Related codes
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 →