How To Tell If Your Car Battery Is Failing

Your battery provides electrical power to the starter motor when you turn your car on. It also provides power to the various electrical devices when the car is off.

The alternator charges it when you are driving. If it is failing, you will start noticing intermittent electrical issues. In the end, the car won’t have enough battery power to start.

What Are the Signs Of A Failing Car Battery?

A failing battery has several easy-to-spot symptoms. However, some of them are common to other electrical components, too. So, we need to double-check that the battery is causing the issues. Watch for these symptoms:

• The engine turns over slowly
• The ignition system clicks, but nothing else happens
• A battery warning light illuminates on your dashboard
• Your onboard electrical devices function erratically
• Headlights and/or taillights are dim or flicker

All the above symptoms can occur if your battery has a very low charge. This may be due to the battery or issues with your alternator or starter motor.

The alternator charges the battery when the car is running. If it fails, the battery will slowly lose charge and eventually go flat. A failing alternator can exhibit many of the same symptoms as a failing battery.

The starter motor is a powerful, small electric motor that helps turn the engine over when you start the car. It requires a few seconds of strong electrical current to operate. If the starter is damaged, it can wear out the battery and you may hear a clicking or whirring sound as you try to start the engine.

How To Ensure You Don’t Replace The Wrong Part

Faulty alternators and starter motors can also cause the symptoms of a failing battery, so we need to diagnose the source of the problem first.

Visual Inspection

Depending on your car’s make and model, the battery may be under the hood or in the trunk. If you aren’t sure, check the owner’s manual. Look out for the following signs: 

Corroded Terminals – a powdery residue can build up on the terminals over time, causing a bad connection. Remove each terminal, clean the connectors, and reconnect everything. Apply some grease to each connector to prevent further corrosion.

Bloated Battery  – This is a sure sign that the battery needs replacing. If it is bulging, the chemical reaction inside the casing has caused the cells to overheat, and the battery won’t be able to hold a charge. It can also leak corrosive battery acid onto the bodywork.

Battery Levels – Certain older batteries will have caps over each set of cells. These require topping up with distilled water periodically. If the levels are low, topping them up may solve the problem. If they have been low for too long, the battery may be ruined. Maintenance-free batteries are sealed and do not need topping up. GMB stocks a full range of advanced Absorbed Glass Mat (AGM) that do not need any maintenance.

Charge Test 

For this part, you will need access to a Multimeter. Set the voltage to 20. Always wait for an hour before testing voltages, as the results may be inaccurate otherwise. 

There are three tests you can run:

1. Turn the car off and switch off all auxiliary devices. Connect the red and black Multimeter connectors to the corresponding battery terminals. It should read at least 12.4 Volts.
2. Turn the key to the ignition position, but do not turn the car on. Switch on some auxiliary devices, such as the headlights, heater, and radio. Attach the Multimeter connectors to the battery terminals again. The voltage reading should not dip more than a few tenths.
3. If the car can still be started, turn it on while checking the voltage readings. They should not dip below 10 volts when the starter is engaged, and it should quickly return to normal once the engine is running.

Do all the above tests indicate a healthy battery, yet you are still experiencing erratic electrical issues? Then, the starter or alternator may be to blame. 

If the voltages are low and you have a battery charger, you can attempt to charge the battery and repeat the tests. If the fully charged battery performs well but is flat a few days later, the alternator may not be charging it when the car is on. Frequent starts with a failing starter motor will also drain the battery charge.

How Much Does A Car Battery Cost?

The following factors influence the cost of an automotive battery:

Stop/start Systems — Advanced onboard electrical devices and stop/start systems put an extra strain on the battery. This requires a more advanced design, which can increase the price.

Battery Type — Flooded or Lead-Acid batteries are more common on older cars and tend to cost less. Absorbed Glass Mat (AGM) batteries are maintenance-free and more common in modern vehicles but tend to cost more.

Battery Size — Each vehicle has a recommended battery size. Your subcompact hatchback’s battery will be smaller than a full-sized SUV.

At GMB, we stock a full range of OE-approved batteries in L2 to L6 sizes. A typical AGM-type automotive battery costs between $150 and $300.

Can I Replace The Battery Myself?

Replacing the battery on most cars is straightforward. You may need a ratchet set or screwdriver to loosen clamps and terminals. Wear protective gloves to avoid the battery acid burning your skin.

A battery is heavy, so be careful not to drop it while handling it. Make sure to connect the replacement battery in the exact same way. Match the black terminal to the black connector and the red terminal to the red connector.

Where Should I Buy A Replacement Battery?

GMB stocks a full range of batteries for most vehicle types. Check your owner’s manual to know exactly what size and type of battery you need. Follow this link to shop our popular replacement batteries.

Never settle for subpar or unproven battery brands. GMB has been an industry-leading OE and Aftermarket automotive product manufacturer since 1943. We have locations on both the east and west coasts of the US, in California and New Jersey. Look at our range of products and contact us to order your replacement battery today.