Robot mower displays E19 and cannot detect rain; continues mowing in wet conditions or refuses to start when dry.

Safety first: Turn OFF the mower before working on the rain sensor or charging station.

• Identify sensor location: On many LawnMaster models, the rain sensor is on the charging station or on the mower top cover.
• Clean sensor: Gently clean the sensor surface with a damp cloth to remove dirt, pollen, and grass sap.
• Check cable: Inspect the rain sensor cable from the sensor to the charging station PCB or mower main board for damage.
• Adjust settings: Use the menu or app to verify rain sensor settings and sensitivity are correctly configured.

If E19 remains and the sensor does not respond to actual rain, replace the rain sensor module. If a new sensor does not resolve the error, the associated control board input may be defective.