Robot lawnmower displays E5 and stops; often after hitting an obstacle or boundary.

Safety first: Turn OFF the main power and disconnect the charging station power.

• Check bumper movement: Press the front bumper in and release it several times. It should move freely and return fully. If it feels stuck, inspect for trapped grass, twigs, or stones and remove them.
• Clean bumper gap: Use a thin brush or compressed air to clean the gap between the bumper and the mower body. Do not use water directly into the gap.
• Inspect bumper switches: If accessible, open the front cover and locate the bumper microswitches or sensor bar. Check for broken plastic mounts or disconnected wires.
• Test operation: After cleaning, power the mower ON and gently press the bumper while it is in test mode (if available) to see if the error reappears.
• Replace components if needed: If the bumper does not trigger correctly or E5 remains, the bumper switch assembly or associated wiring harness may need replacement.