FluidNC Error 9

FluidNCErrorPosition is kept

The controller is in an alarm or jog state, so it refused the G-code.

Position is kept. An error means the controller refused that one line or command, so nothing moved for it. (Hamrun's reading)
What to do
  1. Look for the alarm that came before this error: that's the real problem.
  2. Fix that, then unlock ($X) or home ($H).
What users reported CLAIMED · forum and issue reports, not official
  • Repeated Alarm 3 and Error 9 mid-cut on a 3018 Pro. First blamed on electrical noise; the real cause was the cable chain nudging the Z limit switch. (one owner's report) r/hobbycnc thread, Jul 2026
Official FluidNC message: “GCode cannot be executed in lock or alarm state” source

Got a different message?

Paste it into the decoder. Hamrun's editor checks your G-code before you run it, so a toolpath that leaves the machine's travel or a missing feed rate is caught before the machine stops.

Related codes

  • GRBL 1.1 Error 9: The controller is in an alarm or jog state, so it refused the G-code.
  • grblHAL Error 9: The controller is in an alarm or jog state, so it refused the G-code.

Official text copied from the FluidNC source on 2026-11-01. Steps and the position answer are Hamrun's reading unless marked “firmware says”. User reports are labelled CLAIMED.