Wyze robot vacuum shows C4 and refuses to start or stops shortly after starting; often associated with cliff or drop sensor issues.

Safety first: Power off the robot and remove it from the dock.

• Locate cliff sensors: Turn the robot over. The cliff sensors are small dark windows along the front and sides of the underside.
• Clean the sensors: Use a soft, dry microfiber cloth to gently wipe each sensor window. For stubborn grime, lightly dampen the cloth with water (no chemicals) and dry immediately.
• Check the environment: Very dark carpets, black rugs, or highly reflective floors can trigger false cliff readings. Move the robot to a lighter, non-reflective floor and test again.
• Reset and test: Power the robot back on and start a cleaning cycle in an open area away from stairs and edges.
• If C4 continues: The cliff sensor board or its wiring may be faulty. Internal access requires removing the bottom cover and sometimes the front bumper. If you are not experienced with electronics, seek professional service or contact Wyze support for repair options.