Robot mower displays E4 and stops; often near the boundary wire or when trying to dock.

Safety first: Turn OFF the mower and unplug the charging station from mains before touching any wiring.

• Check charging station LEDs: Most Hecht bases have an indicator LED for boundary signal. If it is off or flashing abnormally, there is a wire or base issue.
• Inspect boundary wire connections: Open the terminal cover on the charging station. Ensure both boundary wire ends are firmly clamped and not corroded. Trim and re‑strip the wire ends if necessary.
• Walk the perimeter: Follow the boundary wire around the garden. Look for cuts from gardening tools, animal damage, or exposed copper. Repair breaks using waterproof Hecht Boundary Wire Connectors.
• Check for shorts: Ensure the wire is not twisted together or touching itself in unintended places, which can short the loop.
• If E4 remains and LED indicates no signal: The Charging Station / Boundary Signal Board may be defective. Test with a spare loop of wire directly at the base; if still no signal, replace the charging station electronics.