¶ What it is
There are several current sensors on the MC board of the printer to sample the current of the motor, when the printer is turned on each time, the resistance of the motor will be detected through the current sensor to determine whether the motor is broken. If the resistance of motor is abnormally high, it is considered that the motor has an open circuit error.
The error that Motor-A has an open-circuit may be caused by the following reasons:
- The cable of the motor is loose - This is the most common issue, and it is solved by simply reconnecting the cable
- The motor is broken - This issue is rare, and it is solved by replacing the motor
- The MC board is broken - This issue is rare, and it is solved by replacing the MC board
¶ Safety Warning
IMPORTANT!
It's crucial to power off the printer before conducting any maintenance work, including work on the printer's electronics and tool head wires. Performing tasks with the printer on can result in a short circuit, leading to electronic damage and safety hazards.
During maintenance or troubleshooting, you may need to disassemble parts, including the hotend. This exposes wires and electrical components that could short circuit if they contact each other, other metal, or electronic components while the printer is still on. This can result in damage to the printer's electronics and additional issues.
Therefore, it's crucial to turn off the printer and disconnect it from the power source before conducting any maintenance. This prevents short circuits or damage to the printer's electronics, ensuring safe and effective maintenance. For any concerns or questions about following this guide, open a new ticket in our Support Page and we will do our best to respond promptly and provide the assistance you need.
¶ Troubleshooting Steps
¶ 1. Check whether the cable of the motor is loose
Start by following this wiki article to remove the rear cover of the printer, to access the MC board.
¶ 2. Locate the motor wires
As shown in the image below, the MC board has 3 motor cables connected.
Motor Z - Bottom left side
Motor B - Bottom right side
Motor A - Middle right side
¶ 3. Try to re-connect each motor to determine the fault
When your printer reports the message that “Motor ___ has an open circuit” it's very probable that one of the motor cables is loose and can be solved by simply re-connecting the appropriate cable.
- If the error message reports that Motor A has an open circuit, you would need to try and re-connect the A motor cable (Motor A - Middle right side)
- If the error message reports that Motor B has an open circuit, you would need to try and re-connect the B motor cable (Motor B - Bottom right side)
- If the error message reports that Motor Z has an open circuit, you would need to try and re-connect the Z motor cable (Motor Z - Bottom left side)
It's recommended to follow these steps for accurate troubleshooting:
- Turn off the printer
- Remove the power cable and the back cover of the printer
- Disconnect and re-connect the motor cable shown in the error message
- Re-connect the Power Cable and confirm if the error message occurs again or not.
If the issue is solved, disconnect the power cable, then re-attach the back cover to the printer before using it.
If the issue persists, follow Step 2 and Step 3 again to try the other cables.
¶ 4. Further troubleshooting for less common faults
Please note that Motor A is the same as Motor B, but motor Z is different. If the HMS reports “Motor-A has an open-circuit”, follow these steps.
- Turn off the printer
- Remove the power cable and the back cover of the printer
- Swap the cable of Motor A and Motor B
- Re-connect the Power Cable, and turn on the printer
- If the HMS still reports that Motor A has an open-circuit, the MC board is broken and will need to be replaced.
If the HMS changes to Motor B has an open-circuit, motor A is broken.
If the HMS reports that “Motor-Z has an open-circuit”, please follow these steps:
- Turn off the printer
- Remove the power cable and the back cover of the printer
- Swap the cable of Motor Z and Motor A
- Re-connect the Power Cable, and turn on the printer
- Export the log file and share it with the Customer Support team so we can provide a solution
¶ Error message
HMS_0300-0600-0001-0001: Motor-A has an open-circuit. There may be a loose connection, or the motor may have failed.
0300-0600-0001-0001
0300-0700-0001-0001
0300-0800-0001-0001
¶ End Notes
We hope the detailed guide provided has been helpful and informative.
To ensure a safe and effective execution, if you have any concerns or questions about the process described in this article, we recommend submitting a Technical ticket regarding your issue. Please include a picture or video illustrating the problem, as well as any additional information related to your inquiry.