What are the reasons for the frequent battery drain in BYD Song MAX?
2 Answers
The reasons for the frequent battery drain in BYD Song MAX: Vehicle parked for a long time: During long-term parking, the battery's charge will continuously deplete. After prolonged parking, the battery may become undercharged, making it unable to start the car. If the headlights are not turned off after parking overnight, the battery may also run out of power. Car battery reaching its service life: Car batteries have a certain lifespan. If not replaced after prolonged use, they may frequently run out of power. The condition of the car battery can be judged by observing the color inside: green indicates normal, black indicates low voltage, and white means the battery has reached the end of its service life and needs to be replaced with a new one. Engine damage: If the car engine's belt becomes loose or breaks, it cannot drive the generator to work, leading to an open circuit. Broken generator wires or loose connections can also cause the battery to discharge without charging.
After repairing cars for so many years, I've frequently encountered cases where the BYD Song Max's battery keeps losing power, mainly due to several reasons. First, the battery itself may be aging or damaged. Typically, its lifespan is only three to five years, and heavy usage accelerates wear. Second, there could be an issue with the alternator, failing to charge the battery sufficiently while driving, leading to low voltage. I've also come across cases where short circuits occurred after modifications, such as improperly installed audio systems, causing power to drain unnoticed. Additionally, forgetting to turn off headlights or the AC after parking can drain the battery overnight. During inspections, I use a multimeter to check if the output voltage is normal—if it's below 13 volts, the alternator likely needs repair. Cold weather also reduces battery performance, so regular maintenance is advised, including cleaning the battery terminals to prevent corrosion. If all else fails, replacing the battery ensures driving safety—don’t wait until you’re stranded on the road to regret it.
