How to Remove Broken Filament Stuck in the AMS 2 Pro Feeder or Internal Hub
If brittle or damp filament snaps inside the AMS 2 Pro (often indicated by clicking noises or a steady red LED when the feeder slot is empty), first unlock the rear PTFE tube and push a 250 mm+ piece of stiff filament through the feeder to force the broken piece out. If the piece is jammed inside the 4-into-1 internal filament hub, you must unscrew the three hub screws, clean the path, and verify the internal Hall sensor magnet rebounds smoothly. Last checked October 25, 2026.
In our AMS 2 Pro red LED troubleshooting guide, a steady red LED means the feeder sees no filament, but the internal filament hub still detects filament inside[cite: 4]. This companion guide walks through Bambu Lab’s official procedure for physically removing broken filament from the feeder tubes and internal hub as of October 25, 2026.
Tools needed (from Bambu’s wiki)
- H2.0 and H1.5 Hex Keys (Allen wrenches)
- A scrap piece of strong filament longer than 250 mm
Method 1: Push the broken piece through the feeder tube (No teardown)
If the filament broke inside the first-stage feeder or visible PTFE tube, try clearing it without opening the shell:
- Unlock the PTFE tube: Press the black pneumatic release button with one hand and pull the PTFE tube out with the other hand.
- Push with a 250 mm+ filament strand: Insert the scrap piece of filament into the feeder inlet and gently push it all the way through until the broken remnant exits the PTFE tube opening. Repeat gently to make sure no small fragments remain.
- Reconnect the PTFE tube: Push the tube firmly back into its original slot until seated.
Method 2: Clean the Internal Filament Hub & check the magnet
If the filament broke deep inside the 4-into-1 internal filament hub (or the steady red LED stays on even after clearing the tubes), Bambu Lab’s wiki specifies inspecting the hub:
- Disassemble the AMS 2 Pro to access the internal filament hub at the rear merge point.
- Remove the internal hub: Unscrew the three screws holding the internal filament hub in place and lift it out. Important: Carefully set aside the shock-proof silicone strip attached to the filament hub so you do not lose it, then remove the hub motor.
- Clear debris and check the Hall sensor magnet: Remove any snapped filament pieces. If no filament is inside the hub yet the slot LED stays steady red, Bambu notes that the internal magnet may not be rebounding smoothly or may be oriented incorrectly. Check that the magnet moves freely and faces the right direction before reassembling.
- Test the slot: Reassemble the unit, power on the printer, go to the Filament screen, select a slot, and tap Load to confirm smooth feeding.