LEDs on the floor nozzle flash and F4 appears, brushroll icon may be lit, brushroll may spin erratically.

Safety first: Turn OFF the vacuum, remove the battery, and detach the nozzle.

• Remove and inspect brushroll: Take out the brushroll and look for a small magnet or metal ring near one end. Clean any dust or hair around this area.
• Clean sensor area: Use a soft brush or dry cotton swab to clean the area on the nozzle where the sensor reads the magnet.
• Check for physical damage: If the magnet ring is cracked or missing, the brushroll should be replaced.
• Reassemble and test: Refit the brushroll and test. If F4 persists, the Hall sensor or nozzle PCB is likely faulty.
• Replace nozzle if needed: In most consumer models, the sensor is integrated into the nozzle PCB, so replacing the entire nozzle assembly is the practical repair.