Robot mower displays E7 and does not charge when docked in the charging station.

Safety first: Unplug the charging station power adapter from the mains before cleaning contacts. Do not short the contacts.

• Clean contacts: Use a dry cloth or fine abrasive pad to clean the metal charging contacts on both the mower and the base station. Remove oxidation and grass sap.
• Check alignment: Place the mower manually into the base and ensure the contacts line up and press firmly together. Adjust the base position on the ground if necessary.
• Inspect power supply: Verify the Parkside power adapter is firmly plugged into the base and the wall socket. Check the output voltage with a multimeter; compare to the rating on the label.
• Check contact wiring: Open the mower housing and trace the wires from the charging contacts to the main PCB. Look for broken solder joints, loose connectors, or burnt marks.
• Battery status: If the battery is extremely discharged or defective, the mower may show E7. Inspect the battery pack for swelling or leakage and measure its voltage.

When to replace: Replace the charging contacts or wiring harness if physically damaged. Replace the power adapter if it has no output. If all hardware is good but E7 persists, the main PCB charging circuit may be faulty.