Diagnose and Fix Error HMS_0300-4101-0001-0003 on Bambu Printers
When your 3D printer displays the code HMS_0300-4101-0001-0003, it is reporting a critical communication failure. The mainboard cannot establish a dialogue with the TMC controller chip that handles the extruder motor. This electronic silence stops any operation immediately. 🚨
Understand the Nature of the Failure
This issue does not arise because the TMC driver detects an internal anomaly, such as overtemperature or lost steps. It is a prior failure: the communication protocol, whether UART or SPI, is not working. The main board sends instructions but receives no confirmation or data from the extruder, generating the error.
Procedure to diagnose the cause:
- Completely disconnect the printer from the power grid and wait a few seconds.
- Access the rear electronics compartment to locate the flat cable that connects the mainboard to the extruder module.
- Thoroughly inspect that the connector is firmly inserted at both ends and check that no pin is bent or missing.
- Visually examine the extruder board for signs of physical damage, such as darkened, burned components, or corrosion.
A loose cable or one with damaged pins is one of the most common causes for this critical communication to fail.
Steps to Restore Communication
If during the review you find a loose connection, reconnect all cables firmly and power on the machine to test. Often, this simple step resolves the issue. If the error persists and the hardware appears intact, the next logical step is to update the software.
Sequence of actions to resolve the error:- Reconnect all cables related to the extruder and mainboard, ensuring optimal contact.
- Update the firmware of the printer to the latest stable version available. A software bug can simulate this communication failure.
- Perform a print test after each step to verify if the HMS_0300-4101-0001-0003 error disappears.
- If the problem continues after these actions, it is very likely that there is a hardware failure on the mainboard or extruder board.
When the Problem Persists
If you have followed all the diagnosis and solution steps without success, the failure points to a defective electronic component. At this point, you must contact Bambu Lab technical support. Provide them with all the details of what you have tried. They will evaluate the case and, if the printer is within the warranty period, handle the replacement of the affected part. Do not attempt to repair boards with SMD components without the proper equipment and knowledge, as you could void the warranty. 🛠️