How does the car battery charger know when the battery is dead?
How does the car battery charger know when the battery is dead? So the battery charger doesn’t really know when your battery is charged it just knows when current is no longer leaving the charger. What does it mean when a car battery is not charged? The battery is shot. The charger indicating a fully charged battery means one of two things: the battery is fully charged, or the battery is faulty and won’t take a charge. A battery that has sat for a month and then expended some energy trying to start the engine is not going to be...