The internal filament hub is the material selection device (4-in 1-out) of the AMS, which is responsible for sending the specified filament to the printer, and pulling the filament that has been sent to the printer back to the AMS.
Filament is stuck in the filament hub, all the PTFE tubes check OK and are well connected.
New filament hub, H2.0 & H1.5 allen keys
Turn power OFF to the printer and disconnect the AMS connection with the printer.
Open the AMS cover, press the button on the filament hub and pull out the PTFE tube.
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Remove 2 screws, and then flip the middle frame upward.
Disconnect the bambu bus cable and the power cable, and remove the middle frame module.
Depress the plastic couplers to disconnect the 4 PTFE tubes.
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Remove 4 screws, and turn the filament hub assembly over.
Disconnect the motor cable, the hall cable and the speed measuring cable, and then remove the filament hub assembly.
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Remove 2 screws, and then remove the motor unit.
Install the motor unit to the filaments hub according to the positioning post and screw holes.
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Lock the motor unit with 2 screws.
Connect the motor cable, the hall cable and the speed cable.
Install the filament hub assembly to the middle frame, and lock in 4 screws.
Arrange the cables, and connect the 4 PTFE tubes.
Place the middle frame into the AMS shell, connect the bambu bus cable and power cable.
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Install the middle frame in place, and lock with 2 screws.
Check the tube bracket, and insert the PTFE tube, try to pull it out to make sure that the tube is well connected.
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Connect the AMS to the printer and turn power ON. Load filament to all slots of the AMS and click "Load" on the screen to start loading the filament.
After the filament in slot 1 loads, choose AMS slot 2 to load the filament in slot 2, and then load filament in slot 3 & slot 4.
If all the loading process functions OK, the replacement is complete and successful.
Otherwise, check the connections of all the cables and PTFE tubes. If no errors are found and malfunction continues, contact the Bambu Lab service team for further assistance.