Repair sequence
Work from top to bottom. Stop when the failure is resolved, verify it with a small test and record the successful setup.
- Unload filament and clean the sensor using the approved method.
- Check the inlet, outlet, PTFE tube, and sensor mount are aligned.
- Inspect the cable and connector while gently moving the harness.
- Test the sensor state in printer diagnostics if available.
- Try a straight piece of known-good standard filament.
- Confirm the configured sensor type and active-high/active-low logic.
- Use manufacturer-supported debounce or sensitivity settings only.
- Complete a monitored runout test before relying on the feature.
Safety and accuracyStay within the printer, material, resin, hotend, build-surface, electrical, ventilation, and personal-protection limits published by the manufacturers. Stop immediately for heater errors, smoke, electrical damage, severe binding, uncontrolled motion, or resin exposure.