# Is there a way to reset a filament motion sensor after it triggers? **URL:** \ **Category:** General Discussion\ **Created:** [August 8, 2022, 1:55am UTC](https://klipper.discourse.group/t/is-there-a-way-to-reset-a-filament-motion-sensor-after-it-triggers/3763 "2022-08-08T01:55:53Z")\ **Posts on this page:** 1\ **Showing post:** 19
**Author:** ![azab2c](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/azab2c/32/5430_2.png) [@azab2c](https://klipper.discourse.group/u/azab2c)\ **Post date:** [June 22, 2023, 2:16am UTC](https://klipper.discourse.group/t/is-there-a-way-to-reset-a-filament-motion-sensor-after-it-triggers/3763/19 "2023-06-22T02:16:28Z")
Thank you for the helpful info @gabe.mi, please correct/confirm my new understanding… The BTT Smart Motion Sensor can only detect motion, the sensor is **not** able to detect whether filament is present or not. So, Klipper infers whether filament has run out when the extruder is pulling filament through, but [no motion is detected by the sensor for some number of millimeters](https://github.com/Klipper3d/klipper/blob/d32a83345518f4bb632bef9ca2de669b35f0e555/klippy/extras/filament_motion_sensor.py#L66). This is why, when no active printing job is running (i.e no extruder movement), the dashboard can only detect motion has occurred since reboot, but has no idea if filament is present or not. Started asking these questions because I’m trying to verify sensor is configured and behaving correctly before printing on my [V1 Engineering MP3DP v4](https://forum.v1e.com/t/mp3dp-v4-azas-build/37251/194?u=azab2c) build. Ironically, looks like I need to print something to verify the motion based runout sensor config/hardware is working 🙂 Update: Did tear down, device can only detect filament motion, not presence, shame… --- _[View the full topic](https://klipper.discourse.group/t/is-there-a-way-to-reset-a-filament-motion-sensor-after-it-triggers/3763)._