Have you ever tried to start your car only to hear a sluggish crank—or worse, complete silence? Your car battery powers everything from starting the engine to the headlights and stereo, so a dead or weak car battery can leave you stuck at the worst possible moment. But the good news is that checking, cleaning, and testing your battery is easy with Tyrepower.
How to Test Your Car Battery
Step 1 - Check Your Battery for Any Damage
Before checking your battery’s charge, take a moment to visually inspect it under the bonnet. Sometimes, obvious signs of damage can tell you immediately that your battery is on its way out.
- Check for swelling or bulging: If the battery case looks bloated, it may have been exposed to excessive heat, which can damage the internal structure. If your battery is misshapen, it’s best to replace it.
- Look for cracks or leaks: If you notice any liquid leaking from the battery, it could be highly corrosive acid. A leaking battery isn’t just a risk to your vehicle—it’s a safety hazard.
Step 2 - Check for Corrosion & Clean the Terminals
Corrosion is a common cause of battery problems. You’ll usually spot corrosion as a white, light blue, or greenish buildup on the battery terminals (the metal posts where the cables attach). Here’s how to check and clean your battery:
- Look at the terminals: Check the battery terminals for signs of corrosion or damage. These can weaken battery performance and affect your vehicle's ability to start.
- Clean the terminals: Wearing gloves and safety glasses, disconnect the battery and apply a paste comprising baking soda and water to the corroded areas with a brush. After the baking soda fizzes and neutralises the acid, gently scrub it away.
- Wipe and tighten the connections: Dry the terminals with a clean cloth before you secure the connections. Loose cables can cause electrical problems, so verify their secure attachment.
Step 3 - Test Your Battery Voltage with a Multimeter
A multimeter is a handy tool for measuring the voltage of your car battery. If you don’t already own one, they’re affordable and easy to find at most auto stores. Here's what to keep in mind when testing your battery’s voltage:
- You should perform battery tests when your vehicle engine has completely shut down.
- Set your multimeter to measure DC voltage (V) at 12 volts because this matches the standard operating voltage of car batteries.
- Connect the probes:
- The red probe goes to the positive (+) terminal.
- The black probe goes to the negative (-) terminal.
- Check the voltage reading: The proper reading of a healthy battery should be at least 12.6V.
- Your battery works normally at this time but requires charging in the near future if it stays between 12.4V and 12.6V.
- If it’s below 12.4V, your battery is likely weakening and could need replacing.
- Check the voltage once more after starting the engine to confirm its accuracy. A large voltage drop indicates that your alternator is failing to recharge the battery correctly.
Step 4 - Conduct a Load Test to Assess Performance
Even if your battery shows a decent voltage, that doesn’t necessarily mean it’s working properly when you try to start the car. A load test checks whether it can handle the demand of starting your car. You can perform a basic load test by doing these steps:
- Let your headlights run for two minutes straight without starting the engine. The battery usage during this test creates a minor power drain comparable to the battery consumption during car engine startup.
- Use a multimeter to check the voltage again while the lights remain switched on.
- Try starting the car. If the engine turns over sluggishly, struggles, or makes a slow cranking sound, it’s a strong sign that the battery is on its way out.
Step 5 - Visit Tyrepower for a Comprehensive Battery Check
DIY testing can give you a good idea of your battery’s condition, but if you're still wondering how you can test your car battery more accurately, bring your car to Tyrepower for a professional assessment. Our team can carry out a full battery and charging system test to ensure everything works as it should.
If a battery replacement is needed, Tyrepower offers high-quality batteries that are built to last. Don't wait until your battery is completely dead to contact us—book your free battery check with your nearest Tyrepower store today.
