Robot lawnmower displays E07 No Charge; mower cannot charge when docked on the NAC charging station.

Safety first: Unplug the NAC power supply from the mains before cleaning contacts or opening the charging station.

• Check power supply: Confirm the wall outlet works by testing with another device. Ensure the NAC power adapter LED (if present) is lit.
• Inspect charging contacts: Clean the metal contacts on both the mower and the charging station with a dry cloth. For heavy corrosion, use fine sandpaper or a contact cleaner, then wipe dry.
• Check alignment: Manually guide the mower into the base. Ensure it sits fully against the charging stops and that both contacts touch firmly.
• Measure output (advanced): With a multimeter and the power supply plugged in, carefully measure DC voltage at the base contacts (refer to NAC specs). No voltage indicates a faulty power adapter or base board.
• Inspect internal charging board: If the base has correct voltage but the mower does not charge, the internal charging PCB or battery management board inside the mower may be defective.

Warning: Do not short the charging contacts with tools. If you are not comfortable with electrical measurements, seek professional service.