Without a healthy battery, your car will go nowhere. Just like your complex body, your vehicle is a complex world of parts and mechanisms, and there are many reasons why the battery runs out.
How to Fix Car Battery Keeps Draining? While these jumper cables may be a quick fix, a dead or unhealthy car battery is annoying and can lead to troublesome and expensive repairs or replacements. But it can also be avoided with proper maintenance, and you know why your car’s battery keeps draining.
What happens if the battery is low?
The battery is a critical component. To maximize its lifespan and functionality and ensure a hassle-free driving experience, you need to make sure your car’s battery is properly charged. When your battery is low, the charging system (i.e. alternator) and starter motor draw too much voltage to compensate for the lack of battery power, so they overwork and fail over time.
Therefore, when the first signs of failure appear, you need to inspect and test the battery, charge or replace it in time. Otherwise, you may be replacing expensive electrical parts without warning.
Car Battery Running Low Guide: The Main Reason Why Your Car Battery Keeps Dying
Loose or corroded battery terminals
Your car’s battery will only work properly if the terminals are properly connected. All terminals must be free of contaminants and fit snugly so that you can’t swing them by hand (you have to be careful with the sidepost terminals, as you may be stripping off the threads and actually breaking into the housing, causing electrolyte leakage).
Battery cables and terminals are susceptible to corrosion over time. In addition, the terminal fittings may become loose. These can hinder the alternator’s ability to charge the battery and power the car, so you may not be able to start the vehicle. You may even turn off or damage your vehicle’s electronic components while driving.
But don’t worry. Corrosion is an unavoidable problem for all types of batteries. Corroded and loose terminals are not a serious problem and can be avoided with regular maintenance. Using a commercial solution and a soft-bristled brush to clean your car’s battery terminals (remember to wear protective gloves and goggles), a simple but effective tip to prevent corrosion is to add a little petroleum jelly to the terminals. Another simple solution is to use liquid electrical tape to create an airtight seal, but you will need to cut it off before removing the battery cable.
Your battery is too old and needs to be scrapped
How to Fix Car Battery Keeps Draining? Nothing lasts forever, including your car’s battery. Depending on how you drive and the climate where you live, a car battery will typically last three to five years. Once your battery has reached the three-year mark, it’s time to monitor it closely.
There are many factors that can negatively affect the lifespan of a battery, including extreme temperatures and frequent short trips. If your car’s battery drains quickly, even after starting, it’s a sign that your battery is old enough and needs to be replaced.
To track the health of your battery and know when you need to replace it with a new one, you’ll need a multimeter or a voltmeter, both of which measure the voltage stored in the battery at a specific time. The power that drives a car is stored in the battery and measured by voltage, and the voltage level in the battery is essentially its state of health.
The battery is fully charged when it is maintained at 12.6 volts or higher. When the battery voltage drops to 12.2, it is only charged at 50%, while when the voltage drops below 12 volts, the battery is “dead” and needs to be replaced.
Test the battery with a multimeter:
- Before testing a car battery with a multimeter, it is important to let the car sit for at least an hour or overnight. This is because the alternator generates electricity and charges the battery, and if the car is running all the time, the amount of charge from the alternator can produce a higher misleading number on the multimeter.
- Place the battery (usually installed in the engine compartment under the hood) on the side of the engine. Set the multimeter to 20 DC voltage by turning the knob on the “DCV” (DC voltage) range to 20, which will allow you to accurately measure batteries stored between 0 and 20 volts (you need to set the multimeter to a specific range every time you use it to test something). The multimeter reading should be 0.00.
- Connect the red (positive, marked with “+”) pen of the multimeter to the red (positive) battery terminals, and the black (negative, marked with “-“) pen” to the black (negative) battery terminals.
Tip – Know the age of your battery: Just like your car tires can age with age even when stored safely, your battery will lose strength as it ages, even without heavy use and proper care. Therefore, when buying batteries, you should always buy new batteries that have been manufactured within the last 6 months.
To find out how old your battery is, you can look at the four- or five-digit date code on the battery compartment lid. All you need is the first part of the code, which consists of a letter and a number, such as A20.
This letter is assigned to each month: A for January, B for February, and so on. The following numbers indicate the year: for example, 9 in 2009, 12 in 2012, 20 in 2020, and so on. Therefore, “A20” means that the battery was shipped from the factory to the local battery wholesale distributor in January 2020.
Car Low Battery Guide: The alternator is not charging the battery properly
Your car relies on batteries to start and run the engine. But while your vehicle is running, your battery relies on an alternator to help it stay charged. The alternator generates electricity from the car’s mechanical energy and uses this electrical energy to charge the battery and power a variety of electrical accessories such as lights, radios, and air conditioners.
If the alternator is working properly, i.e. if it provides an optional charge to the battery, the life of the battery will be maximized. But whether it is overcharging or undercharging, it will shorten the life of the battery. Additionally, if your alternator isn’t working properly, it won’t be able to charge the battery effectively, so you may not be able to start the car.
If the battery is in good condition, and if there is a slow start problem while the car is running, that is, when the engine is hot, the alternator may be the culprit.
Just like your battery, you must also test the alternator regularly or if you have problems with difficulty or not starting. They have to go hand in hand.
Please note that you must always test the battery before testing the alternator. This is because the battery ignites the engine, and once the engine is running, it spins the alternator and this rotation keeps the battery charged. If the battery is too weak, it won’t make the car run to test the alternator. You’ll need to test the alternator twice to check if it’s working properly at idle, not draining from electrical fittings, and working at a higher speed with heavy use.
- Test the no-load voltage of the alternator: Allow the engine to idle and turn off all electrical accessories that may be using electricity, including lights, dashboard and stereo. Repeat the above battery test with a multimeter. A healthy alternator should produce readings between 13.1V and 14.6V when the engine is running at normal idle. Anything outside of this range means that your alternator is undercharging or overcharging the battery, both of which can shorten the life of the battery.
- To test the load voltage of the alternator to see if it works properly with heavy use: Have your assistant keep the engine running at 2,000 RPM. Open all electrical accessories and reconnect the multimeter. A healthy and powerful alternator should read 13.0 volts and above. Anything below 13.0 volts indicates that the alternator is weak and should be checked by a professional.
Parasitic effects on the battery
How to Fix Car Battery Keeps Draining? While your engine is running, the alternator supplies power and charges the battery. However, when your car is turned off, the alternator can’t charge the battery, while your battery can still power a variety of accessories, including interior lights, clocks, and radios.
Most of these don’t usually drain your car’s battery, but there are still some electrical accidents that can drain your battery. Interior lights (including door lights) and damaged fuses can be potential sources of additional stress. To avoid this type of accident (often referred to as battery parasitism), you should make it a habit to turn off all lights and make sure all doors are fully closed and locked, including the trunk and glove compartment, before leaving the car.
A Guide to Running Low Batteries in Cars: Extreme Weather Conditions
Your vehicle’s battery is also sensitive to extreme temperatures, which is why drivers are more often experiencing problems with difficult start-up on cold winter mornings and very hot summer days. “Younger” batteries with a shorter life can better withstand extreme cold or heat, but older batteries weaken with age and are therefore less resistant to extreme temperatures and may even die altogether.
According to the AAA Center for Automotive Research, a car’s battery weakens by about 60% at 0°F, while at 32°F it loses 35% of its strength. Extreme temperatures can cause irreversible damage to your battery, and with them expensive replacement costs.
First, extreme heat evaporates the vital liquid in the battery, which weakens its ability to charge. It can also speed up the corrosion process, which can damage the internal structure of the battery and shorten its lifespan.
At the same time, severe cold weather can freeze the battery. This will cause the sides of the case to bulge, short-circuit the plates, and the battery will no longer be charged. Lead-acid and lithium-ion batteries are particularly vulnerable to extreme cold weather.
The battery has enough low temperature tolerance when charged at 100%, but this strength wanes as it wears out. At 50% charge, your battery may freeze overnight at a temperature of -10 F. During the winter months, the current used to start the engine is twice as high as it would be required in normal weather. That’s why on cold winter mornings, you’re more likely to have problems with difficulty starting.
Because temperature has a big impact on your car’s battery, you should choose a battery that is suitable for your local weather conditions. It’s best to consult your owner’s manual as well as a certified mechanic. Batteries specifically designed to withstand extreme heat are often labeled “S” or “South”, while cold-weather batteries are often labeled “N” or “North”. In some cases, if you live in a hot climate, you can replace your AGM battery with a traditional immersion battery to maximize its lifespan.
Frequent short trips with old batteries
As you may already know, generally the more times you drive on the highway at a sustained high speed, the better for your car, and driving a lot in stop-and-go traffic can wear out many car parts prematurely. The same goes for your car’s battery.
What happens when you’re on frequent short trips, when starting the engine draws a lot of power from the battery, and the alternator may not have enough time to properly charge the battery between drives. Over time, this can significantly weaken the battery and shorten its lifespan, especially if your battery is already old.
Tips: How to Fix Car Battery Keeps Draining
Choose the right battery type for your vehicle
First and foremost, to ensure optimal performance and longevity, you must equip your car with the right battery. Each car requires a different amount of power and a different size of battery, so each car needs a specific type of battery. Therefore, you need to consult your owner’s manual to find out which battery is suitable for your car, or ask the mechanic which battery is best for your car.
For example, if you often drive your vehicle for off-road travel, you’ll need a battery that can withstand constant vibrations in rough terrain. Many cars are equipped with AGM to support an increasing number of electrical components, and the charging system may be configured specifically for AGM batteries. In some cases, you can replace an AGM battery with a traditional flooded battery to extend its life in hot climates (although flooded batteries require more maintenance, as shown below).
Choose a battery that is easy to maintain
Car batteries require regular maintenance to stay healthy. Despite not being a handyman, one way to save time and better ensure the health of your battery is to buy a maintenance-free battery in the first place. If allowed, obtain a gel-type or AGM battery. Thanks to advanced technology, these batteries are leak-free and do not require the same special attention as flooded lead-acid batteries.
Flooded lead-acid batteries require more maintenance. They lose water during the charging cycle, so they only need to be replenished with distilled water every 2-4 weeks to function properly and stay healthy. In addition, they should be equalized occasionally to ensure that each battery is charged equally. You can do this by applying a controlled overcharge every 30-90 days.
Low Car Battery Guide: Perform regular load tests
While almost all car batteries today are said to be maintenance-free, regular inspection and maintenance are still crucial for any machine. It is recommended that you test the battery with the alternator (no-load and load test), preferably at least once a year, for 3 years in mild or cold climates, or once every 2 years if you live in a cold climate. Doing so tests the battery’s ability to maintain voltage while in use, and the results will tell you when it’s time to replace it.
Useful accessory: float/trickle charger
All types of batteries are prone to a problem called natural discharge or self-discharge. It is an unavoidable process in which an internal chemical reaction reduces the charge stored by the battery without any connection between the electrodes or any external circuits. Therefore, if you need to store your vehicle during the winter or other situations where it has been idle for long periods of time, you should invest in a float charge to keep your battery fully charged.
Also known as trickle chargers, storage chargers, or maintenance chargers, these floating chargers prevent excessive self-discharge of the battery when not in use for long periods of time. To prevent this, the charging rate of the float charge is equal to the battery’s natural self-discharge rate.
Most trickle chargers have built-in circuitry to prevent overcharging, so you can leave the charger running 24/7 without worrying about overcharging the battery, although some models don’t and can damage the battery through overcharging. Although the floating charger automatically monitors and charges the battery, it is always recommended that you check regularly to make sure everything is still in good working order.
When you’re using it, it’s a good idea to also get a portable battery starter and keep it in your vehicle as an emergency tool. These increasingly compact accessories allow you to easily and quickly start your vehicle without having to rely on another vehicle.
