Robot mower will not start mowing; display shows E001 immediately after power-on or when START is pressed.

Safety first: Remove the mower from the lawn, place it on a flat surface, and switch the main power OFF. Keep hands away from the blades.

• Check emergency stop button: On many Greenworks robot mowers there is a red STOP or emergency button on the top cover. Make sure it is fully released. Press it down and then twist or pull (depending on model) to reset.
• Verify main power switch: Turn the main power switch OFF and back ON. Inspect the switch area for damage or water ingress. If the switch feels loose or does not click, it may be faulty.
• Inspect docking station safety loop: Ensure the charging station is powered (LED on the station should be lit). Check that the low-voltage power supply is firmly plugged into the station and the wall outlet. If the station has a safety loop or key switch, make sure it is in the ON position.
• Check low-voltage cable and connectors: Inspect the cable from the power supply to the charging station and the contacts on the front of the mower for corrosion, bent pins, or broken insulation. Clean contacts with a dry cloth.
• Power cycle the mower: After checks, turn the main switch ON, place the mower in the charging station, let it wake up and clear the error. Try starting a manual mow.

If E001 persists after these steps, the internal safety relay or wiring harness may be defective. Contact a Greenworks service center.