Robot mower displays E07 and refuses to start; often after rain or washing the mower.
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety first: Ensure the mower is on a flat surface, power OFF, and battery disconnected before opening the housing.
- Confirm mower is on ground: Make sure all wheels are firmly on the ground and the mower is not resting on an obstacle.
- Clean underside: Grass buildup can hold the chassis in a lifted position relative to the wheels. Clean around the wheel arms and chassis supports.
- Locate lift sensor: On many LawnMaster models, the lift sensor is near the front or rear axle, often a small switch or Hall sensor that detects chassis movement. Check that it moves freely.
- Dry the mower: If the mower was recently wet, allow it to dry in a sheltered, ventilated area for 24 hours. Do not use high-pressure water on the mower.
- Inspect wiring: Check the lift sensor harness and connector at the main control board for corrosion or loose pins.
If E07 remains after cleaning and drying, the lift sensor module may need replacement. If replacing the sensor does not help, the main control board lift input could be faulty and should be evaluated by a technician.