Bambu Lab P2S – Extruder Filament Sensor

Replacement extruder filament sensor for the Bambu Lab P2S 3D printer. This sensor is located directly in the extruder and is used to detect:

presence of filament in the extruder
position of the filament cutter lever

Proper functioning of the sensor is key for automatic filament loading and unloading, detection of the end or missing material, and for preventing errors where the printer reports filament where there is none – or vice versa.

Key features

Filament presence detection The sensor recognizes whether filament is loaded in the extruder and helps manage the process of loading, unloading, and pausing when the filament breaks or runs out.
Monitoring the position of the filament cutter lever Thanks to the detection of the filament cutter lever, the printer can correctly evaluate the state of the filament after cutting and follow up with further operations without errors.
Stable and accurate sensing The design of the sensor with Hall/current sensing and precise mechanics ensures long-term stable function in the dynamic environment of the extruder.
Easy replacement according to the official guide Installation follows the guide on the Bambu Lab Wiki. The replacement can be handled even by an advanced user at home – no special service tool is required.
Compact dimensions, low weight The small dimensions of the sensor easily fit into the extruder space without affecting the print head movement.

Typical symptoms of a faulty sensor

Consider replacing this sensor if your Bambu Lab P2S shows, for example:

the printer reports filament in the extruder even when it is completely unloaded
fails to load new filament – the printer behaves as if it were already loaded
repeated error messages related to filament detection at the extruder
problems with correct switching between filaments via the cutter system

In these cases, the extruder filament sensor is usually faulty or mechanically worn.

Compatibility

Compatible devices: Bambu Lab P2S (P2S extruder)
Designed exclusively as a spare part for the P2S extruder, do not use in other models without verification.

Package contents

Approximate according to similar Bambu Lab sensors (P1 / H2S). Actual content may vary slightly depending on the production batch.

1× Extruder Filament Sensor for Bambu Lab P2S
2× mounting screw (type BT2)
possibly a self-adhesive / fixing element according to the manufacturer

Materials and processing

Sensor material: plastic + metal elements
Color: Black (possibly black-metallic)

Compact design matches the design of original Bambu Lab parts and maintains the appearance and functionality of the original printer.

Installation recommendations

Before replacement, turn off the printer and disconnect the power supply.
Follow the official Bambu Lab Wiki guide step-by-step for replacing the extruder filament sensor on the P2S.
During assembly, ensure correct insertion of the connector and placement of the wiring so that it does not restrict the movement of the print head.
After replacement, perform a filament loading and unloading test and check if the printer correctly recognizes the filament state.

Who the product is for

Owners of the Bambu Lab P2S 3D printer who:
- are solving filament detection issues in the extruder
- want to have a spare sensor in stock to minimize downtime

Thanks to this sensor, you will restore full filament management functionality on the Bambu Lab P2S and minimize the risk of print errors caused by poor material detection.

Key features:

Filament presence detection and filament cutter lever position
Key element for correct filament loading and unloading in the extruder
Helps prevent filament detection errors and "empty" printing
Compact and lightweight design made of plastic and metal
Suitable as a spare part in case of failure or wear of the original sensor
Easy assembly according to the instructions on the Bambu Lab Wiki