What is the method to check the battery level of a vehicle?

[SanThomas]

To check the battery level of a vehicle, you can: 1. Observe the color of the battery indicator to understand its status; 2. Use a multimeter to measure the battery voltage; 3. Check the remaining battery level on the car's dashboard. Methods for battery maintenance include: 1. Charge the battery promptly when the ammeter shows insufficient power; 2. Adjust the electrolyte density according to standards based on different regions and seasons; 3. Add distilled water or special replenishing fluid when the electrolyte is low; 4. Limit each engine start to no more than 5 seconds; 5. Start the car periodically if the battery is unused for a long time; 6. Regularly check if the small holes on the battery cover are ventilated; 7. Inspect the battery terminals for oxidation; 8. Examine all parts of the circuit for signs of aging or short circuits.

[DelNicole]

Last time my car had difficulty starting, so I specifically learned how to check the battery status. The simple method is to first turn off the engine and wait half an hour for the voltage to stabilize. Use a multimeter set to the 20V DC range, touch the red probe to the battery's positive terminal (+) and the black probe to the negative terminal (-). A healthy battery's no-load voltage should be around 12.6V; if it drops below 12.2V, it means the battery is almost dead. Nowadays, many cars come with battery monitoring systems, and a battery icon on the dashboard will turn yellow as a warning. Some high-end cars can even display the specific health status on the central control screen. Pay special attention in winter, as low temperatures are particularly draining on the battery. If the voltage drops below 11.8V, the car will basically be unable to start.

[StCharlie]

I've used three methods to check battery levels: the most accurate is the specialized battery tester at repair shops, which directly reads capacity and lifespan percentage; next is purchasing a charger with a battery level display myself—just plug it into 220V to see the remaining capacity; for temporary emergencies, there's the car key method—after turning off the engine, turn on the headlights and honk the horn twice. If the lights noticeably dim or the horn sounds muffled, there's an 80% chance the battery is low. Regular batteries typically last 2-5 years, so if you notice slower starts after three years, it's time to prepare for a replacement.

[LeonardoFitz]

Most new cars nowadays can check the battery status themselves. For example, in my car, when the ignition is on but the engine is not started, pressing the CAR button on the steering wheel twice and selecting 'Vehicle Status' on the central display will show the real-time battery voltage. The key is to check the value after the car has been stationary for 30 minutes: if it's below 12.4V before a cold start in the morning, it's best to drive for half an hour to recharge that day. Owners who have modified their dash cams should pay extra attention, as excessive standby current can easily lead to chronic battery discharge. It's also important to regularly open the hood and check the electrodes for white crystalline deposits.