There’s nothing more frustrating than having a dead car battery while you’re running late. If you’re wondering what can drain your car battery overnight, here are the possible culprits:
The great news is that you can prevent them and keep your battery ready to power your ride.
There are many reasons a car battery loses charge overnight. Not all of them are obvious, but most are preventable.
While newer vehicle models will turn the lights off automatically, older units don’t have this feature. If your ride falls in the latter category, failing to switch the lights off after exiting can potentially waste a lot of battery power.
Illuminated headlights drain energy quickly, however, leaving your interior light on will lead to the same problem. If your vehicle is malfunctioning, it could struggle to register when a car door has been closed, resulting in the interior light staying on overnight.
Lights that are left on overnight will drain the car’s battery until there’s no power left.
Give your vehicle a look-over after closing its doors. Just a quick check to make sure all the lights are off can save you a lot of power. It’s a good habit to develop since you can improve the overall longevity of your car by minimizing battery drain.
Most newer vehicles make checking over them a lot easier. Some have alert systems that let drivers know if they’ve left any part of the car on.
Lights aren’t the only parts that drain power. Essential dashboard parts like the clock, radio, and sound system all drain energy from the car battery.
This normally wouldn’t be a problem because cars tend to charge their batteries whenever they’re in motion.
However, a damaged relay could cause cars to use up power even when the vehicle is parked and the engine is off. This parasitic draw can drain the battery if left unresolved.
Keeping an eye out for any accessories that are still active after shutting the door can increase your car battery’s longevity. Don’t leave things like chargers and other plugged accessories, as they’ll continuously drain power from the battery even if your car isn’t running. Unplug and remove them before leaving your vehicle.
Older car batteries are sensitive to sharp changes in temperature. Whether it’s due to the severe heat or the cold, you might notice performance issues with your car battery in extreme temperatures.
Fortunately, newer batteries are more resistant to weather conditions.
Protect your car from the elements. Blanketing your vehicle with a car cover could work for sedans and SUVs, but your best bet would be to park it in your garage. Garages are perfect for keeping your vehicle out of extreme temperatures and inclement weather.
If your car battery keeps draining overnight, the battery connections could be either loose or damaged. Sometimes the positive and negative terminals connected to the car battery corrode or come loose, making it difficult for the battery to transmit power.
If your car battery is already damaged, your best bet would be to replace it with a new one. Driving with damaged battery connections is dangerous because you run the risk of stalling out in the middle of the road. You could also put your vehicle’s electric components in jeopardy.
The alternator is responsible for charging the car battery while you drive. So if it takes any damage, it might affect the output of energy, leaving the battery with less power to work with.
If your vehicle consumes more electricity than it generates, your car battery will inevitably drain and run out of power. On average, an alternator should generate 13.5 to 14.5 volts. If your alternator is underperforming, it could be responsible for your drained battery.
Like with most car parts, proper maintenance is key, so regularly check on your alternator. If it’s old or too damaged, it might be time to replace it.
Make sure to double-check it for any damage in the diodes as well. An alternator with damaged diodes is going to gradually lose power as electricity leaks—even when the car is off.
Though the alternator generates energy for your car battery while you drive, it takes time to do so. This means short drives can cause you to waste a lot of power. The power used up starting the car will eventually overtake the power generated by the alternator.
In addition, short trips put tremendous strain on your car’s battery. In other words, making short trips too frequently can shorten the lifespan of your car battery.
If you have to use your vehicle for a short time, you can leave it running. Letting it run for even 10 minutes can help improve the overall longevity of your battery, preventing it from draining itself overnight.
If your car battery loses charge overnight, it could be a sign that it’s on its last legs.
Bear in mind that some car batteries can expire earlier than anticipated due to harsh weather conditions, extreme temperatures, and bad driving habits.
On average, a car battery lasts 4-5 years. If the one in your vehicle is older than that, it might be time to consider getting a replacement. Driving with an old battery isn’t dangerous, but it is incredibly inconvenient.
A car that’s been sitting in the garage for too long can lead to a dead battery. In most modern vehicles, electronic systems continue to use power even when the engine is off. This is why your car might refuse to start after leaving it parked for a few weeks.
A brief 15-minute drive every week should be enough to help maintain your car battery’s state of charge. This also helps keep the alternator and electronic systems in good condition.
Be sure to drive for at least 15 minutes because quick drives can also harm your car battery.
With so many possible causes, figuring out why your car battery keeps dying can take some time. Here are some tips on how to diagnose what’s draining your car battery:
Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.