How to Check if the Car Battery Has Power?

[DelLillian]

Methods to check if the car battery has power are: 1. Observe the inspection window on the battery—green indicates normal, black means it needs charging, and white signifies damage; 2. Check the indicator window on the battery—blue or green color indicates normal, while white means no power; 3. Press the horn—a loud sound indicates power, while a weak sound suggests low power; 4. Observe the battery warning light on the dashboard—if it stays lit, it means the battery is out of power. Function of the battery: It stores electrical energy to supply power for car starting, ignition, lighting, signals, and audio-visual equipment. Working principle of the battery: Car batteries use lead-acid batteries based on the primary cell principle. When the load is connected, the lead on the negative plate reacts with sulfuric acid to form lead sulfate and lose electrons, while the lead oxide on the positive plate reacts with sulfuric acid to form lead and water, gaining electrons, thus generating electric current.