If you’ve owned a car, you’ve had a dead battery. The inconvenience is virtually unavoidable throughout a lifetime of driving. Thankfully, it’s a simple problem to fix. If it’s bad, replace it, or if it’s simply weak, recharge it!
There are a few methods for charging a car battery. Some can be done at home, while others might require a trip to the local auto parts store. Some require an overnight charge, while others can be done in an hour. Obviously, there’s some variability.
With that in mind, Car Bibles has put together a useful guide for how to inspect, test, diagnose, and charge a battery that can help you get back on the road. Let’s get to it.
Common Car Battery Problems
A low charge is not the only issue that can affect the performance and functionality of a battery. Check for these common problems while the hood’s popped.
- Bad Battery Cables
Inspect all connections and retighten as necessary. Inspect the cables themselves for cuts, burns, degradation, or anything else that could affect performance and replace as necessary.
- Corroded Battery Terminals
Inspect the battery terminals for corrosion and clean as necessary. For more information, read How To Clean the Battery Terminals On a Car.
- Discharged Battery
If left sitting for long periods of time, a battery slowly discharges its energy and might not have the strength to start your vehicle. When it’s dead, it needs a charge or a replacement.
What Type of Charger Do I Need?
There are three main types of devices that can be used to funnel power into a battery. A battery minder or maintainer is typically used to keep a level state of charge while a vehicle is in storage or not in use. These are often known as trickle chargers.
A battery charger is similar to a minder but can provide more energy for a quicker charge. Some modern devices can do the job of both a maintainer and a charger. Additionally, they will automatically shut off when a battery is fully charged to prevent overcharging and damaging the battery.
The third type of charger is a fast charger. Most auto parts stores such as O’Reilly’s, Autozone, or Advanced Auto Parts will provide free charging with their on-site fast chargers. This typically takes 30-60 minutes. Once you’ve selected your charging method, it’s time to charge!
What You’ll Need To Charge A Car Battery
- New battery, if needed
Working on your car can be dangerous and messy, so here’s exactly what you’ll need to ensure you protect yourself from battery corrosion and prevent shocking yourself.
How To Charge A Car Battery
Follow these steps to diagnose and fix your car battery.
Check the Voltage
- With the vehicle off, pop the hood. The latch should be located underneath the driver’s side dashboard and steering column to the left of the wheel.
- Use a multimeter to check the voltage of the battery.
- If between 12.0-12.4 volts: Jump the car, if necessary, and drive around for 30-60 minutes. The car’s system should recharge the battery.
- If lower than 12 volts: Use a battery charger.
Charging the Battery
- Park the vehicle in an out-of-the-way position where the battery charger can easily connect to a plug without tension on the line. Do not connect the charger wires across high-traffic corridors.
- Turn the car off, pop the hood, and locate the battery.
- Use a socket wrench to disconnect the battery terminals and place them out of the way, separate from each other.
- With the charger plugged in and in the off position, connect the positive clamp to the positive terminal. Look for red caps and/or a “+” symbol.
- Connect the negative clamp to the negative terminal. Look for the black cap and/or a “-” symbol.
- Turn the charger on and set it to 12V.
- Charge the car for as long as necessary.
- Turn the charger off and remove the cables in reverse order.
- Use the multimeter to once again check the voltage of the battery. It should read 12.6 volts or above when the car is off and between 13.7-14.7 volts when the car is running.
- If the battery does not recharge, replace it.
Charge A Car Battery With Confidence
Over the years, Car Bibles’ editors have run into dozens of dead batteries. Here are a few tips to keep the lights on.
- A quick way to check your battery levels is through the headlights. If you flip the headlights on and they look dim, you likely need to replace your headlights.
- It’s more difficult, but it is possible to jump-start a car without cables. Car Bibles’ How To Effectively Jump Start a Car details how.
Car Battery Charging FAQs
You have the questions, Car Bibles has the answers!
Q: Can You Charge a Dead Car Battery?
A: All batteries have a point of no return that requires total replacement, but yes, a dead car battery can be recharged and brought back to life, depending on its condition and age.
Q: Can I Charge My Car Battery at Home?
A: Yes. With the correct charger and space, anybody can charge a struggling battery at the house.
Q: How Long Should You Run Your Car To Charge the Battery?
A: If you’re attempting to recharge your battery simply by driving it around, give it a solid 30-60 minutes.