Robot vacuum displays E5 and refuses to start cleaning, often after being moved or dropped

Safety first: Turn OFF the robot and remove it from the charging base.

• 1. Locate cliff sensors: Turn the robot upside down. Identify the downward-facing sensors near the front edge (usually 3–4 small windows).
• 2. Clean sensor windows: Use a soft, dry microfiber cloth or cotton swab to gently wipe each sensor window. If there is sticky residue, lightly dampen the cloth with water and dry immediately.
• 3. Check for physical damage: Inspect the sensor windows for cracks, deep scratches, or missing plastic. Damaged windows can distort the infrared signal.
• 4. Test on a light surface: Place the robot on a flat, light-colored floor away from edges. Power it ON and start a cleaning cycle. Avoid dark carpets or black mats during testing, as they can be interpreted as a drop.
• 5. Internal harness check (advanced): If the error persists, remove the bottom cover and verify that the cliff sensor harness is firmly connected to both the sensor board and the main PCB.

Warning: Do not cover the cliff sensors with tape or stickers to bypass them; this can cause the robot to fall down stairs. If cleaning and harness checks do not clear E5, the cliff sensor board should be replaced by a qualified technician.