Bambu Lab HMS error code 0300-0D00-0001-0003 is an extrusion monitoring error within the 0300-0D00 subgroup, which covers nozzle flow and extrusion feedback. This error indicates the printer detected insufficient or abnormal extrusion — the most common interpretation being a partial or full nozzle clog that is preventing normal filament flow.

What the Error Means

Bambu Lab printers monitor extrusion via the extruder motor feedback and, in some models, a filament flow sensor. Suffix 0001-0003 in the 0300-0D00 extrusion subgroup indicates a flow anomaly during active printing — the extruder was commanded to push filament but the output did not match expectations. Heat creep (where the melt zone extends too far up the heat break), carbonized filament in the nozzle, or printing at a temperature too low for the loaded filament all contribute to this condition.

Step-by-Step Fix

1. Pause or end the current print job and allow the hotend to reach a safe cooling temperature before handling.
2. Heat the nozzle to 10–15 °C above the normal printing temperature for the loaded filament to try to soften any partial clog.
3. Perform a cold pull: heat to 90 °C, insert filament and push gently, then allow to cool to 90 °C and pull firmly. Repeat 2–3 times and inspect the pulled filament tip for debris.
4. If the cold pull does not clear the clog, heat to 250 °C and manually push filament through the nozzle with moderate hand pressure.
5. Check that you are printing at the correct temperature for the filament type — printing PLA with a nozzle set to 180 °C, for instance, will cause under-extrusion.
6. Inspect the PTFE tube in the heat break for burnt or carbonized filament residue and replace if it appears dark or deformed.
7. Replace the nozzle if repeated cold pulls do not restore normal flow.

Parts Required

• Replacement nozzle (appropriate size and material for your model)
• PTFE tube (if inspection reveals degradation)
• Filament for cold pull procedure

If the error appears immediately after a nozzle replacement or with a new filament type, contact Bambu Lab support to rule out a temperature calibration or sensor issue.