FluidNC Alarm 12

FluidNCAlarmPosition isn't set yet: home first

A limit switch is active, but FluidNC can't tell which way to move to clear it.

Position isn't set yet: home first. Homing can't start. (Hamrun's reading)
What to do
  1. Jog the machine off the switch by hand or with a jog command.
  2. If switches share one input, check the config file says which axis each belongs to.
Official FluidNC message: “Ambiguous Switch” 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.

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.