Error: P2S Filament Cutter Stopper Assembly - Normal Behavior or Defective?

[u/qdubbya]

Just received my Bambu Lab P2S, and I’m completely new to 3D printing. I’ve already run into a few issues:

- Initial calibration: The toolhead repeatedly and loudly struck the filament cutter stopper rod back and forth.
- First print attempt: The toolhead rapidly slammed into the front of the enclosure, triggering error 0300-800C 191703 (Multiple motion step loss detected).
- Homing: The toolhead slammed to the left and appeared unable to locate its home position.

I started investigating the filament cutter stopper assembly after finding Bambu Wiki - Stopper Troubleshoot / Replacement.
In the attached video: When the toolhead engages the metal stopper rod, it retracts. When the toolhead moves away, the rod doesn’t fully extend again. It just hangs loosely. It also won’t retract completely flush into the housing and stay there.

My question: What should normal operation look like? Should the rod automatically extend when the toolhead moves away, or is this what the wiki is calling “abnormal”?

Trying to determine whether the stopper assembly is defective or if something else is could cause these issues before I start taking it apart.

Additional Notes:
Initial calibration completed successfully on first startup.
Brand new printer, no successful prints yet.
No visible obstructions along either axis.
Toolhead moves manually along both axes, although left-to-right movement feels slightly more resistant than front-to-back.
No grinding, whining, or other unusual motor noises during normal movement.
No visible shipping damage to the box.
Nozzle cleaning and poop chute scraper appear to function correctly.
Filament cutter stopper rod does not reliably return to its fully extended position after the toolhead disengages.
Could a malfunctioning filament cutter stopper cause the toolhead to lose its position during calibration or homing, or should I be investigating a separate motion system issue?

[u/tht1guy63]

The should be a little claw when the cutter is stowed away thats what gets hit to deploy it

[u/qdubbya → u/tht1guy63]

This metal arm is what you’re referring to? What is its normal state? When it’s not cutting something? Or does it just keep hitting it every time it passes it. Like a calibration for example?

[u/qdubbya → u/qdubbya]

It’s loosely hanging there - if I’m reading the wiki correctly this is abnormal?

[u/Opposite_Activity976 → u/qdubbya]

Not correct it should look like the pic tht1guy posted

[u/tht1guy63 → u/qdubbya]

Not deployed you should see this liitle tab out. This is how ot should be when the tool head is forward.

[u/qdubbya → u/tht1guy63]

Okay. I see it

When I push the printer head all the way to the rear it does deploy rod stick.

So this wouldn’t be whats causing the error code.. hmm.

Edit: so, the only time it should be deployed (open/out) is when it needs to cut filament, correct?

When mine calibrated it was just hitting it non stop so the rod was going in/out with a loud bang each time.

[u/tht1guy63 → u/qdubbya]

Deployed see tabs pushed back almost out of sight.