- 3D printers
- 3D printer
0300-0200-0001-0003
Bambu Lab 0300-0200-0001-0003 on a 3D printer: heater fault
Risk level
High
Professional inspection is recommended.
Urgency
Medium
Quick answer
Bambu Lab HMS 0300-0200-0001-0003 appears when the nozzle heater runs at full power and does not reach temperature in time. Switch off, let it cool, check the silicone sock and, if it continues, open a ticket.
Safety first
Stop and check this first
- Do not disable or bypass the thermal protection or change the firmware to clear the alert: it is what cuts the heat when the temperature does not add up. Do not open the printer's power supply or mains board: anything at mains voltage is for the service team.
- The nozzle runs very hot: Bambu Lab asks you not to touch it and to switch off and unplug the printer before any maintenance. Wait for the toolhead to cool before putting your hands near it.
Safe checks you can perform
- Switch off and let the toolhead cool
- Hotend silicone sock
- Reconnect the NTC cable
- Support ticket with photo or video
Leave these tasks to a qualified professional
- Do not attempt this professional task: Heater and NTC measurement
- Do not attempt this professional task: Test with a complete new hotend
- Do not attempt this professional task: TH board 10 pin connector or FPC
What a technician must be able to justify
Technician visit
These are the steps they must carry out and show you. Tick them as they work: if steps are skipped, do not accept a part swap.
These are not instructions for opening or handling the equipment yourself. They are the checks that should support a technical conclusion.
Heater and NTC measurement
What they doThe technician measures resistance at room temperature with a multimeter. Bambu Lab gives typical values of about 12 ohms for the heater and 50 to 100 kilohms for the NTC on the X1, about 10 ohms and 100 kilohms on the P1, and about 7 ohms and 100 kilohms on the A1.
They must show youboth readings against Bambu Lab's values for your model.
In writingthe measurements and the part replaced.
Test with a complete new hotend
What they doBambu Lab suggests as a quick check fitting a complete new hotend and seeing whether the error goes away.
They must show youthat the error does not return with the new hotend.
In writingthe hotend reference and the result.
TH board 10 pin connector or FPC
What they doWith a V8 TH board, the technician replugs the 10 pin connector and looks for burn marks; with a V9 board, they reseat both ends of the FPC.
They must show youthe state of the connector.
In writingwhat was checked and whether the TH board was replaced.
Before accepting a part or repair
Nothing has been shown yet. Do not accept a part swap based on the code alone.
Follow these steps
Note: Follow the documented order. An error code identifies the affected system, but it does not prove by itself which part has failed.
Switch off and let the toolhead cool
- Who:
- you.
- How:
- switch the printer off and unplug it before touching anything, as Bambu Lab requires, and wait for the nozzle to be cold.
- Result that matters:
- the toolhead is cold and without power.
- If the screen still shows a high temperature:
- wait longer before getting close.
- If it is cold:
- you can look at the silicone sock.
- Evidence to keep:
- time of the alert and a photo of the screen.
Evidence: Bambu Lab Wiki: HMS_0300-0200-0001-0003: The nozzle temperature is abnormal, the heater is over temperature.
Hotend silicone sock
- Who:
- you.
- How:
- with the printer cold and off, check whether the silicone sock is missing, has fallen off or is badly damaged, as Bambu Lab describes.
- Result that matters:
- whether the sock is whole and held firmly.
- If it is missing or broken:
- it must be replaced before printing again.
- If it is whole and fitted:
- the cause is in the heater, the NTC or their connectors.
- Evidence to keep:
- photo of the sock.
Evidence: Bambu Lab Wiki: HMS_0300-0200-0001-0007: The nozzle temperature is abnormal, the sensor may be open circuit.
Reconnect the NTC cable
- Who:
- you, if you follow the guide for your model.
- How:
- with the printer off, remove the toolhead front cover (magnetic on the X1) and plug the NTC cable back in, as Bambu Lab describes. Do not pull on the wires.
- Result that matters:
- whether the alert disappears when you switch back on.
- If it disappears:
- it was a poor contact; note it.
- If it returns:
- do not take more apart; go to support.
- Evidence to keep:
- photo of the connector before and after.
Evidence: Bambu Lab Wiki: HMS_0300-0200-0001-0003: The nozzle temperature is abnormal, the heater is over temperature.
Support ticket with photo or video
- Who:
- you.
- How:
- if the alert stays, open a technical ticket with Bambu Lab and include a photo or video of the problem and the HMS code, as the article itself asks.
- Result that matters:
- support has the code and the evidence from the first message.
- If they ask for more data:
- add the printer log and the exact model.
- If they propose a spare part:
- ask which test justifies it.
- Evidence to keep:
- ticket number, photos and video.
Evidence: Bambu Lab Wiki: HMS_0300-0200-0001-0003: The nozzle temperature is abnormal, the heater is over temperature.
Still not solved
If the error persists, stop here. See what the technician must do and show you.
Where this code applies
A code is meaningful only inside the right product and version context.
Primary scope
- System
- 3D printers
- Brand
- Bambu Lab
- Product type
- 3D printer
Known code variants
- 0300 0200 0001 0003
- Bambu Lab boquilla sobretemperatura
- Bambu Lab nozzle heater over temperature
- HMS_0300-0200-0001-0003
What it means
Bambu Lab explains that nozzle control has a heater and an NTC sensor. When the heater runs at full power but does not bring the nozzle to the target temperature in time, the toolhead TH board triggers the over temperature error as a safety measure. The causes it lists are a broken or badly fitted silicone sock, a heater or NTC that is badly installed or faulty, connectors with poor contact or the TH board. The quick check it suggests is fitting a complete new hotend.
Warnings and stop conditions
- Criticaleditorial warning
Do not disable or bypass the thermal protection or change the firmware to clear the alert: it is what cuts the heat when the temperature does not add up. Do not open the printer's power supply or mains board: anything at mains voltage is for the service team.
Evidence: Bambu Lab Wiki: HMS_0300-0200-0001-0003: The nozzle temperature is abnormal, the heater is over temperature.
- Highsource verified
The nozzle runs very hot: Bambu Lab asks you not to touch it and to switch off and unplug the printer before any maintenance. Wait for the toolhead to cool before putting your hands near it.
Evidence: Bambu Lab Wiki: HMS_0300-0200-0001-0007: The nozzle temperature is abnormal, the sensor may be open circuit.
Symptoms and causes
Probable causes · in order
- Silicone sock broken or badly fittedPossible
If the silicone sock is missing, broken or badly fitted, Bambu Lab lists it as one of the situations that cause this error.
Evidence: Bambu Lab Wiki: HMS_0300-0200-0001-0003: The nozzle temperature is abnormal, the heater is over temperature.
- Heater or NTC sensor badly fitted or faultyPossible
If the heater or the NTC are not installed properly or fail, the nozzle does not reach temperature or the reading is wrong.
Evidence: Bambu Lab Wiki: HMS_0300-0200-0001-0003: The nozzle temperature is abnormal, the heater is over temperature.
- Heater or NTC connectors with poor contactPossible
Poor contact in the connectors makes the system misread the temperature and trigger the alert, according to Bambu Lab.
Evidence: Bambu Lab Wiki: HMS_0300-0200-0001-0003: The nozzle temperature is abnormal, the heater is over temperature.
- Toolhead TH boardLess common
If hotend, connectors and wires are fine, Bambu Lab leaves the TH board as the remaining cause.
Evidence: Bambu Lab Wiki: HMS_0300-0200-0001-0003: The nozzle temperature is abnormal, the heater is over temperature.
Virtual technician
Does 0300-0200-0001-0003 still appear after these checks?
Answer a few questions to narrow down the likely cause and the safest next action. Guidance only - it never replaces a professional.
Sources and technical references
- 1
Bambu Lab Wiki: HMS Home Page, List of Error Codes for Bambu Lab 3D Printers
Bambu Lab · 2026 · official_doc
- 2
Bambu Lab · 2026 · official_doc
- 3
Bambu Lab · 2026 · official_doc
Was this entry useful?