F3 error appears, vacuum stops shortly after starting, no obvious blockage

Safety: Remove the battery and do not continue to run the vacuum if it repeatedly stops with F3.

• Rule out airflow issues: Ensure filters are clean and there are no blockages, as these can cause motor strain.
• Listen for abnormal sounds: When it runs briefly, note any grinding, squealing, or surging sounds from the motor area, which indicate internal motor wear.
• Check for burning smell: A hot, electrical smell suggests motor failure.
• Service or replace motor unit: The tachometer sensor and motor driver are typically integrated with the main motor assembly or PCB. Replacement requires disassembly of the handheld body and should be done by a qualified technician.