Symptoms
- Charger light doesn't turn on or stays red/blinking indefinitely
- Battery shows no change in charge level after hours on the charger
- Charger gets warm but battery indicator doesn't move
- Battery was left fully drained for an extended period
Likely causes
- CommonDeeply discharged batteryLithium batteries left at zero charge for a long time can enter a protective state that resists normal charging.
- CommonDirty or corroded charging contactsDebris on the battery or charger contacts prevents proper current flow.
- PossibleFaulty chargerChargers can fail internally, especially after being exposed to moisture or heat.
- PossibleFailed battery cell or management circuitAfter several years, some cells inside the pack may no longer accept a charge.
What to do
- Clean the battery and charger contacts with a dry cloth to remove dirt or corrosion.
- Try a different power outlet to rule out a dead outlet.
- Let a deeply discharged battery sit on the charger for at least an hour, since some packs need time to wake up their protection circuit.
- Check the charger's own indicator light behavior against the manual to interpret error states.
- Test the same charger with a different compatible battery, if available, to isolate whether the charger or battery is at fault.
- Replace the battery or charger based on which one fails to work with a known-good counterpart.
Tools and parts
- Dry cloth
Replacement mower battery chargerSearch: “cordless mower battery charger replacement”
Replacement battery packSearch: “cordless mower battery pack”
When to call a pro
If both battery and charger seem fine individually but won't work together, a dealer can test the pack's internal cells.
Safety
Use caution
Never attempt to open or charge a battery that is visibly swollen, hot, or damaged; stop use and dispose of it at a battery recycling center.