FANUC Alarm OS-149 — Assert VMAIN … … …

Manufacturer wording — Assert VMAIN %d %d %s
The manual prints placeholders; your controller fills them in with the real group, axis or number.

FANUC OS-149 (“Assert VMAIN … … …”): An assert occurred on the VMAIN processor. First check: Record and report the parameters following the 'Assert MAIN' text to the FANUC or FANUC Robotics Help Hotline.

Updated 2026-09-17 · LogrobotLM reference

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 →