Wrong Push Direction Right Extruder

Bambu Lab H2D
1

Hi,

I couldn’t find a similar issue on this forum, so I’m posting here.

I replaced the MC board because my H2D printer stopped powering on. After replacing the board, I performed a factory reset and tried to print something.

I have an AMS 2 PRO connected to the right extruder. However, when I tried to print, it failed to load the filament properly. The filament reaches the right extruder, but the motor that should push the filament into the nozzle is rotating in the wrong direction (counter-clockwise). As a result, the filament doesn’t enter the nozzle.

After several failed attempts, the printer gives me the error: “Filament buffer signal is abnormal.”

I then connected the AMS 2 PRO to the left extruder, and it prints perfectly. So I believe the issue is specific to the right extruder.

I also removed the right nozzle to check for jams, but there is no broken filament inside. I made a video showing that the filament drive wheel is spinning counter-clockwise when it should be pushing filament into the nozzle.

Any suggestions on how to fix this?

Video link: https://youtube.com/shorts/cU_khA11Jd8

Thanks in advance!

2

It’s turning the right way before it turns backwards. I know you said you removed the nozzle to see if there were any jams - but I suspect your jam would be above the nozzle / in the extruder gear area.

I would take it apart further than just the nozzle and look. I bet you find a jam in there somewhere.

3

I tried to insert the filament manually. If I push it gently, it doesn’t go in, but if I push it firmly, it goes down and comes out of the nozzle (preheated to 220°C).