What happened?
The printer displays the message "Failed to home the X-axis. Make sure there is no obstacle on the X-axis".
Error name: Homing error X
Error code: #31304 (CORE One) #17304 (XL)
The error is most likely caused by a bad movement of the print head along the X-axis.
How to fix it?
Make sure the X-axis can move correctly
Make sure there are no obstructions in the path of the X-axis. For example, there might be a piece of filament stuck around the belt, or on a linear rail, from a previous print.
Check the belt tension
A loose or overtightened belt can cause inconsistent movement that can trigger the error. Check the belt tension, following the dedicated guide for your printer model.
Motor pulley
CORE One
To access the pulley attached to one of the XY motors, follow the below steps:
- Remove the side panel on the needed side.
- Left side: remove 11 rivets to release the panel.
- Right side: release the filament sensor by removing two screws from the handle, then remove 11 rivets to release the panel.
- Slightly loosen the belt tension, by slightly loosening by the same amount the two belt tensioner screws.
- Remove the four M3x35 screws securing the motor.
Corner view Bottom view - Slightly raise the motor to make the pulley visible. Note the different distance between pulley and motor on each motor, and that one of the pulley set screws is aligned with the flat part of the motor shaft.
X-motor (right) Y-motor (left)
XL
Without disassembly, inspect the pulley attached to each XY motor to conicide with the position in the below pictures, and at the same time with one of their set screws aligned with the flat part of the motor shaft.
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| Left-side XY motor | Right-side XY motor |