Robot Mower Not Charging? Here's How to Fix It

MA MowAutonomous Editorial Team · Updated 2026-06-23 · 10 min read

If your robot mower isn't charging, the problem is usually one of five things: dirty charging contacts, misaligned charging station, faulty power supply, battery failure, or software issues. This guide walks through each in order of likelihood.

1. Clean the Charging Contacts (Most Common)

Dirty charging contacts are the #1 cause of charging issues. The contacts on both the mower and the charging station can accumulate dirt, grass clippings, and corrosion over time. Fix: Unplug the charging station. Use a dry microfiber cloth to wipe the contacts on both the station and the mower. For stubborn corrosion, use a cotton swab with isopropyl alcohol. Don't use water or abrasive cleaners.

2. Check Charging Station Alignment

If the mower isn't docking correctly with the charging station, it won't charge. Fix: Watch the mower dock — it should approach the station straight on, not at an angle. If it's approaching at an angle, the station may be misaligned. Use a bubble level to ensure the station is perfectly level. The station should also be on a flat surface — even a slight slope can cause docking issues.

3. Verify Power to the Charging Station

Check that the charging station's power supply is plugged in and the outlet has power. The station should have an LED indicator that's lit when powered. If the LED isn't lit: (1) try a different outlet, (2) check your circuit breaker, (3) try a different power supply (if you have a spare). GFCI outlets (the kind with the test/reset buttons) sometimes trip — press the reset button.

4. Battery Failure

If the mower is docking correctly and the station has power but the battery still won't charge, the battery may have failed. Lithium-ion batteries typically last 5-8 years, but they can fail earlier if exposed to extreme temperatures or deep discharged. Fix: Contact the manufacturer for a replacement battery. Most cost $150-$400 depending on capacity.

5. Software/Firmware Issues

Sometimes charging issues are caused by software bugs. Fix: Update the mower's firmware via the app. If the firmware update fails, try a factory reset (check your mower's manual for the reset procedure). Note that a factory reset will erase your lawn map — you'll need to re-map your lawn.

6. Temperature Issues

Lithium-ion batteries won't charge below 32°F (0°C) or above 104°F (40°C). If your mower has been sitting in extreme temperatures, bring it indoors for a few hours to let it reach room temperature before attempting to charge. The charging station should also be in a shaded location — direct sun can overheat the battery during charging.

When to Replace the Battery

Replace the battery if: (1) it won't hold a charge at all, (2) runtime per charge has dropped to less than 50% of when new, (3) the battery is more than 7 years old, (4) the battery is visibly swollen or damaged. Order replacement batteries directly from the manufacturer — aftermarket batteries may not work correctly and can void your warranty.