My Car Battery Won’t Hold a Charge. What Do I Do?

Reviewed by

William Guzenski, ASE Certified Master Automobile Technician

Contact Center Manager and Technical Reviewer at CarParts.com

Written by CarParts.com Research Team - Updated on September 4th, 2023

Reading Time: 3 minutes
Summary
  • Your car battery won’t hold a charge if it’s old, corroded, or your car has a damaged alternator.
  • If your battery won’t hold a charge, check the battery condition, the voltage, and the state of charge before charging the battery.
  • It’s a good practice to replace your car battery every three years, but keep an eye out for corrosion as it can wear out a battery faster than usual.

Attempting to start a vehicle and failing is aggravating. That’s what happens when you have a dead car battery. The car battery allows your vehicle’s starter to start the engine and power its electronics. You can get stranded in the middle of nowhere if your car battery is faulty or depleted.

Why your Battery Won’t Hold a Charge

Here are some possible reasons why your battery won’t hold a charge:

Old Battery

Old car batteries are likely to lose their ability to hold a charge. If you’re not sure about your car battery’s age, you can use the alphanumeric code on the date sticker to determine its age. These codes are sometimes engraved on the battery itself. The first two characters in the code should tell when the battery was made. The first character contains a number from zero to nine that corresponds to the year in which the battery was made. The second character is a letter from A to L that corresponds to the month in which the battery was made. For example, the code 6B means the battery was made in February 2016. Some manufacturers might write the code in reverse, but it means the same.

Severe corrosion can affect your car battery’s performance and prevent it from holding a charge.

Faulty Alternator

A dead battery can be the result of a malfunctioning alternator. A faulty alternator won’t be able to charge your battery while the engine is running and cause the charge in the battery to deplete much faster. If your vehicle shuts down seconds after jumpstarting the battery, you might have a problem with your vehicle’s alternator.

Corrosion

Battery corrosion looks like white or blue residue sitting on the terminals. Severe corrosion can affect a battery’s performance and prevent it from holding a charge. If you have corroded battery terminals, you might want to take your car to a mechanic and have your battery thoroughly cleaned.

Parasitic Drain

If your battery is good but continually goes dead after the vehicle has been sitting for a while, you might be dealing with a parasitic drain. A parasitic drain occurs when one of the car’s electrical devices (i.e., the dome light, one of the onboard computers, etc.) stays powered up when the ignition key is turned off.

If the voltmeter reads anything much below 12.65 volts, it is not fully charged.

What to Do When Your Battery Won’t Hold a Charge

Not all batteries are built the same way. You could end up doing more damage to your vehicle if you attempt to fix its battery without the necessary automotive skills or knowledge. We recommend taking your vehicle to a licensed mechanic for an inspection. They could run tests to determine what is causing your car battery to fail. Here are some of the things that a mechanic might do:

Inspect Battery Condition

Factors such as age and corrosion can affect a battery’s ability to hold a charge. A mechanic will inspect your car battery’s condition to determine if it needs to be cleaned or replaced.

Check Battery Voltage and State of Charge

The mechanic might attach a voltmeter to the positive and negative battery terminals to gauge the state of charge of the battery. If the voltmeter reads anything much below 12.65 volts, it is not fully charged. Since the state of charge doesn’t necessarily tell you the condition of the battery, professionals will also test the health of the battery using a load tester or digital analyzer.

Charge Battery

Batteries can also lose charge when they’re not being used. Once the mechanic has ruled out a bad battery or other electrical problems, they might use a charger to charge the battery.

When to Replace Car Battery

Some car batteries can last up to five or six years with proper maintenance. However, corrosion, inactivity, and extreme temperature changes can shorten a car battery’s life. Generally, you should replace your car battery every three years to avoid problems.

How Much Do Car Batteries Cost?

Depending on the brand, warranty, dimensions, product fit, and type, a battery replacement will usually cost anywhere from $50 to $300. Additional labor costs could range from $30 to $100. The price may vary depending on local rates.

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.

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Published by
CarParts.com Research Team and William Guzenski, ASE Certified Master Automobile Technician
Tags: battery