Mower displays E11 and stops when encountering obstacles; bumper seems unresponsive or overly sensitive.

Safety first: Turn OFF the mower and disconnect the battery before working near the bumper or blades.

• Check bumper movement: Gently press the front bumper in and release. It should move freely and return to its original position without sticking.
• Clean debris: Remove grass, mud, or stones lodged between the bumper and chassis. Clean the sliding surfaces with a dry brush.
• Inspect springs and mounts: Look underneath the front edge for broken or missing bumper springs or mounting clips. Replace any damaged hardware.
• Test switches: If accessible, manually actuate the bumper microswitches and listen for a click. A multimeter can be used to verify continuity when pressed.
• Check wiring: Follow the bumper harness to the main board and ensure the connector is fully seated.

If E11 continues after mechanical and wiring checks, the bumper sensor assembly may need replacement.