Robot vacuum reports E9 or bumper error; it keeps backing up or spinning even on open floor.

Safety first: Turn the robot OFF before manipulating the bumper.

Steps to try:

• 1. Check bumper movement: Gently press the front bumper at several points. It should move in and spring back freely. If it feels stuck, proceed to cleaning.
• 2. Clean bumper gap: Use a thin brush or compressed air to remove dust, hair, or debris from the gap between the bumper and the body.
• 3. Inspect for impact damage: Look for cracks or deformation that might cause the bumper to bind.
• 4. Test operation: Power ON and start a cleaning cycle on an open area. Lightly tap the bumper to confirm the robot reacts and changes direction.
• 5. Internal inspection (advanced): Remove the top or front cover to access the bumper switch board. Check that the micro‑switches or optical sensors are aligned and that the cable to the main PCB is secure.
• 6. Replace bumper sensor board: If E9 persists and the bumper moves freely, the collision sensor board may need replacement.