Error Codes & Klipper Messages
The Neptune 4 Pro runs Klipper directly, so errors appear as Klipper messages on the screen and in the web interface console:
| Message | What it means | What to do |
|---|---|---|
| Heater extruder not heating at expected rate | The hotend is not warming up as fast as expected | Check the heater cartridge and thermistor connectors; replace a torn silicone sock |
| ADC out of range | A thermistor reading is impossible — usually a broken wire or loose plug | Power off and reseat or replace the thermistor |
| Move out of range | The G-code asked for a position outside the printer's limits | Use the correct printer profile in the slicer and re-home |
| MCU shutdown / lost communication with MCU | The mainboard or toolhead board stopped responding | Power-cycle; if it repeats, check the toolhead cable |
| Probing failed / probe triggered prior to movement | Leveling sensor problem or something on the bed | Clean the nozzle and bed, retry leveling |
Neptune specific
- Bed temperature errors can come from either zone of the dual-zone bed. Check both bed connectors under the bed.
- After a Klipper error, use Firmware Restart in the web interface before printing again.