Is your car battery dead? You may be able to jumpstart your car and get back on the road.
Imagine being stuck on the side of the road with a dead car battery, and the weather is getting colder as night approaches. This can leave you stranded and cause unnecessary stress. But knowing how to deal with a battery dead in a car is crucial for every driver.
This comprehensive guide will discuss the causes of dead car batteries, how to identify them, and how to fix them.
Signs of a Dead Car Battery
Before learning how to fix a dead car battery, it's essential to recognize the common signs that indicate a weak car battery.
Some of these signs include:
- The engine struggles to start or doesn't start at all
- Dimming headlights and interior lights
- Electrical systems malfunctioning (e.g., power windows, radio, etc.)
- Battery warning light on the dashboard
- Swollen battery case
- The battery smells like rotten eggs (sulfuric acid)
If you experience any of these signs, have your car's battery tested immediately to determine if you need a new car battery.
Possible Causes of a Dead Car Battery
There are several reasons why your car battery dies:
- Age. Car batteries have a limited lifespan, typically ranging from 3 to 5 years. As the battery ages, its internal components wear down, and its ability to hold a charge decreases. Eventually, it will no longer provide sufficient power to start the engine. For example, a 5-year-old battery struggles to start the car on cold mornings due to its diminished capacity.
- Extreme temperatures. Both extremely hot and cold temperatures can negatively affect battery life. High temperatures can cause the battery's electrolyte to evaporate, reducing its capacity, while low temperatures can slow down the chemical reactions within the battery, making it harder for the battery to provide enough power to start the engine. So, a car parked in direct sunlight during a heatwave may experience battery failure due to the evaporation of the electrolyte. On the other hand, a car left overnight in freezing temperatures might struggle to start in the morning.
- Parasitic drain. Parasitic drain occurs when electrical devices or systems continue drawing power from the battery even when the engine is off. This can be caused by faulty wiring, malfunctioning components, or simply by forgetting to turn off accessories like headlights or the radio. Keeping the dome light on overnight can completely drain the battery, making it impossible to start the car in the morning.
- Frequent short trips. Many short trips without giving the alternator enough time to recharge the battery can lead to a discharged battery. The battery provides the initial power to start the engine, and the alternator recharges the battery once the engine is running. If the engine doesn't run long enough, the battery won't have a chance to recharge fully. For example, driving only a few minutes to and from work daily may not allow the alternator enough time to recharge the battery, leading to a dead battery over time.
- Corroded battery terminals. Corrosion on the battery terminals can impede the flow of electrical current between the battery and the vehicle's electrical system. The buildup of sulfate crystals on the terminals can lead to poor connections and ultimately cause the battery to die. So, a car sitting unused for an extended period may develop corroded battery terminals, preventing it from starting even if the battery itself is still functional.
- Alternator issues. The alternator is responsible for recharging the battery while the engine runs. If the alternator is malfunctioning, it may not adequately charge the battery, causing it to lose power and eventually die. For instance, a car with a failing alternator might experience flickering headlights or other electrical issues before the battery dies.
How to Start a Car with a Dead Battery: Jump Starting
When your vehicle's battery is dead, jumpstarting is a quick and temporary solution to get your vehicle running again.
Here's how to do it:
- Find another car with a fully charged battery and park it close to your vehicle, ensuring both engines are off.
- Locate both car batteries' positive (+) and negative (-) terminals.
- Connect one end of the red jumper cable to the dead battery's positive terminal and the other to the charged battery's positive terminal.
- Connect one end of the black jumper cable to the negative terminal of the charged battery and the other end to an unpainted metal surface on your car's engine block (not the dead battery's negative terminal).
- Start the car's engine with the charged battery and let it run for a few minutes.
- Perform a battery test by starting your car. If it starts, let it run for at least 15-20 minutes to recharge the dead battery.
Remember to follow safety precautions during this process, such as wearing gloves and eye protection.
How to Charge a Dead Car Battery
If your dead battery car doesn't start after jump starting, the battery may be completely dead and require charging.
Consider the following steps:
- Remove the battery from your car, ensuring the engine is off and the ignition key is removed.
- Clean the battery terminals with baking soda and water to remove corrosion.
- Follow the instructions in your owner's manual to determine the appropriate voltage and amperage settings for your battery charger.
- Connect the charger's positive cable to the battery's positive terminal and the negative cable to the negative terminal.
- Plug the charger into an electrical outlet and turn it on.
- Monitor the charging process, ensuring the battery doesn't overheat or swell.
- Once the battery is fully charged, disconnect the charger and reinstall the battery in your car.
Replacing a Dead Car Battery
If your dead car battery doesn't hold a charge after being jump started or charged, it's time to replace it.
To replace a dead battery:
- Purchase a new battery that is compatible with your vehicle. Check your owner's manual for specifications.
- Remove the old battery from your car, disconnecting the negative cable first, followed by the positive cable.
- Clean the battery tray and terminals using a mixture of baking soda and water.
- Install the new battery, connecting the positive cable first, followed by the negative cable.
- Properly dispose of the old battery at an auto parts store or recycling center.
How to Test a Car Battery
Here are easy steps for testing a car battery using a multimeter:
- Park the vehicle and turn off the engine. Make sure your vehicle is parked on a level surface, the engine is turned off, and the ignition key is removed.
- Set up the multimeter. Turn on the multimeter and set it to the DC voltage setting (usually indicated by a "V" with a straight line). Ensure the voltage range is set to 20V or higher.
- Locate the battery terminals. Open the hood of your car and locate the battery. Identify the (+) positive and (-) negative battery terminals.
- Connect the multimeter to the battery terminals. Attach the red probe from the multimeter to the positive terminal and the black probe to the negative terminal. Make sure the probes have a secure connection to the terminals.
- Read the battery voltage. Once the probes are connected, the multimeter will display the battery's voltage. A fully charged car battery should read around 12.6 volts or higher. If the reading is below 12.4 volts, the battery may need charging or could be nearing the end of its life.
- Test the battery under load (optional). To test the battery under load, have someone start the engine while you observe the multimeter's reading. A healthy battery should maintain a voltage above 9.6 volts during the cranking process. If the voltage drops significantly below this level, the battery may be weak or faulty.
Interpreting the Results
- 12.6V or higher. The battery is fully charged and in good condition.
- 12.4V - 12.6V. The battery is partially charged and may need charging.
- Below 12.4V. The battery is discharged or potentially faulty and may require charging or replacement.
If you suspect your battery is not holding a charge or has other issues, it's advisable to consult a professional mechanic for further testing and potential replacement. Remember that these tests provide a basic assessment of your car battery's health. Consider using a dedicated battery tester or seeking professional assistance for a more comprehensive evaluation.
Preventing Dead Car Batteries
To avoid dealing with a battery dead on car situation, follow these tips:
- Regularly inspect your battery for signs of corrosion, swelling, or leaks.
- Clean the battery terminals periodically using a mixture of baking soda and water.
- Test your battery's voltage and performance at least twice a year.
- Avoid making frequent short trips that don't allow the alternator to recharge the battery fully.
- Replace your battery every 3-5 years, depending on its condition and performance.
Choosing the Right Car Battery
Choosing the right car battery ensures your vehicle's performance and reliability. It will provide the necessary power to start your engine and support your car's electrical systems.
Here's a detailed guide on how to choose the correct car battery:
1. Check Your Owner's Manual
Your vehicle's owner's manual contains specific information about the type of battery compatible with your car. This information includes the battery size, power specifications, and any other requirements related to the battery. Always refer to your owner's manual before purchasing a new battery to ensure compatibility.
2. Determine the Battery Size
Car batteries come in different sizes, which are referred to as "group sizes." The group size indicates the battery's physical dimensions (length, width, and height), as well as the position of the terminals. Choosing the correct group size ensures the battery will fit appropriately in your car's battery tray and connect securely to the terminals.
3. Consider the Cold Cranking Amps (CCA) and Cranking Amps (CA)
Cold Cranking Amps (CCA) measure the battery's ability to start the engine in cold temperatures (0°F or -18°C). A higher CCA rating means the battery can deliver more power during cold starts. Choosing a battery with a good CCA rating is essential if you live in a region with cold winters.
Cranking Amps (CA), also known as Marine Cranking Amps (MCA), measures the battery's starting power at 32°F (0°C). Like CCA, a higher CA rating means the battery can deliver more power during engine starts. While CA is not as critical as CCA, it's still important when choosing a battery.
4. Evaluate the Reserve Capacity (RC)
Reserve Capacity (RC) is how long a fully charged battery can power your vehicle's electrical systems if the alternator fails. A higher RC rating means the battery can support your car's electrical systems longer without the engine running. This is essential, especially if your vehicle has many power-hungry accessories.
5. Choose the Right Battery Type
There are several types of car batteries available in the market, including:
- Flooded (wet cell) batteries. These are the most common and affordable type of car battery. They contain liquid electrolytes and require occasional maintenance, such as topping the electrolyte levels and cleaning the terminals.
- Enhanced Flooded Batteries (EFB). EFB batteries are an improved version of flooded batteries, offering better performance, longer life, and lower maintenance requirements.
- Absorbent Glass Mat (AGM) batteries. AGM batteries use a glass mat separator to hold the electrolyte, making them more vibration-resistant and providing more consistent power delivery. They are maintenance-free, have a longer lifespan, and are suitable for vehicles with advanced electrical systems or start-stop technology.
- Lithium-ion (Li-ion) batteries. Li-ion batteries are lightweight, have a high energy density, and can be charged quickly. However, they are more expensive and less common in standard passenger vehicles.
Consider your driving habits, climate, and vehicle requirements when choosing the right battery type.
6. Check the Warranty
Choose a car battery with a good warranty covering both a free and prorated replacement period. A longer warranty period indicates the manufacturer's confidence in the battery's quality and performance.
7. Purchase from a Reputable Brand
Select a battery from a reputable brand that produces reliable and high-quality batteries. Some well-known car battery brands include Optima, Interstate, Exide, and Bosch.
Choosing the Best Mechanic for Changing Car Dead Batteries
If you are unsure about your skills in following these steps above to replace a dead car battery, it's best to hire a best professional mechanic.
In the past, you needed to tow your car to a local garage or auto shop for assistance with a dead battery. Nowadays, there are mobile mechanics who can provide on-site repair and maintenance services, including changing dead car batteries. If you don't know anyone, you can search "mobile mechanic near me." This is especially helpful if you're stuck in a place you are not familiar with.
When selecting a mobile mechanic for car battery replacement services, check reviews, ask whether they're insured, and clarify hidden charges. Mobile mechanics may charge for their services based on the time and difficulty of the job, as well as additional fees such as mileage and parts. If possible, ask them also about their experience and qualifications. You may not have enough time to compare prices, but you can easily find a trusted mechanic online who can provide excellent service and help get your car running in no time.
Final Thoughts
Knowing how to fix a dead car battery can save you time and money when stuck on the road. By recognizing the signs of a dead battery, understanding the causes, and learning how to jumpstart, charge, or replace a battery, you'll be better prepared to handle this common automotive issue. Remember to take preventive measures to prolong your battery life and avoid future dead battery situations.
Men pushing a dead vehicle / Photo by Peter Trones on Unsplash