This usually indicates that during the unloading process of the CFS lite, both the printer and feeder have executed the unloading action, but the Filament Sensor in the Toolhead still detects filament. Common causes include:
Abnormal resistance in the PTFE tube, making filament retraction difficult;
The filament was not cut, preventing it from exiting the Toolhead;
The extruder is clogged, causing the filament to get stuck;
The Filament Sensor is faulty and continuously detects filament.
Check the PTFE tube Inspect whether the PTFE tube is excessively bent, kinked, or too long, which may cause high resistance during unloading. Refer to: CFS Lite Filament Tube Installation and Placement Guidelines
Inspect the extruder Open the Extruder Lever on the right side of the Toolhead. Observe the filament condition at the Extruder Gear:
If there is a clear clog, remove the front cover of the extruder and clean the Extrusion Assembly. Refer to: SPARKX i7 Extruder Cleaning and Maintenance Guide
Manually remove filament (if no clog is found)
Keep the Extruder Lever open (do not reinstall it yet);
Locate the corresponding slot in the CFS lite;
Press and hold the button above that slot while pulling the filament outward;
It is recommended to fully remove the filament, cut off the tip, then reload it into the CFS lite.
Note: After completing the process, remember to reinstall the Extruder Lever.
Check filament detection status
Check whether the filament detection indicator on the Toolhead turns off:
If it turns off → the printer has returned to normal;
If it remains on → the filament detection system may be faulty.
In this case, refer to Filament Detection Abnormal Troubleshooting to determine which component needs replacement, or contact after-sales support for further assistance.