Essential Vehicle Maintenance: Batteries

The other day we discussed how to properly check all of the fluid levels in your vehicle. Keeping an eye on all of your fluids is extremely important in ensuring the proper functioning and longevity of your vehicle.  You don’t need to break down what an encoder motor  is, or exactly how diesel injection pumps work, but there are other maintenance tasks  that should not be overlooked. The first one we will talk about in this short series is the maintenance of your car battery.

Your car battery is usually located towards the front of your car. You will know if your car battery is critically low if your car is having trouble turning over. Checking the battery before problems occur is a good idea, but requires a trip to the local auto parts store, or a special piece of equipment – a handheld voltage meter. To check the battery life using a handheld voltage meter, touch the meter leads to the positive and negative battery terminals with the ignition key is OFF. A reading of 12.66 volts is a fully charged battery, 12.45 volts is 75% charged, 12.24 volts is 50% charged, and 12.06 volts is 25% charged. If you don’t own a voltage meter, you can always take your battery to a local auto parts store that sells batteries and ask them to test it for you. They can tell you how much charge your battery has left, and if you should change it. 

You should also check your battery for corrosion around the positive and negative terminals. If you have corrosive build up on your battery terminals, it’s important to clean them. To clean them you will need eye protection, gloves, a soft brush (like a toothbrush), distilled water, and baking soda. Keep in mind that adding baking soda to the acid build up on your battery terminals causes an exothermic reaction that produces heat – proceed slowly, adding the baking soda slowly and deliberately and do not get it anywhere but on the corrosion.

 Make sure to FIRST remove the battery cables from the battery terminals. Remove the negative one first, then the positive. If there is excess corrosion you may also need a pair of locking pliers to wiggle and lift upward until the clamp comes off the terminal post. Treat the corrosion like crystallized acid, because that’s what it is – don’t get it in your eyes or on your skin or clothing.

Examine the cables and clamps for excess wear or corrosion. If you find them severely eaten away, you should replace them. Secure the loose cables so they don’t accidentally flop over onto the terminals – you could get an electric shock. To remove the corrosion, pour baking soda directly onto the posts. Use a damp or wet toothbrush to scrub the baking soda into the terminal posts and cable clamps. If this isn’t doing much, use a battery terminal cleaner brush purchased at the auto parts store, or a plain wool pad. 

 Dry everything off with a clean rag. Apply grease or petroleum jelly onto the posts – this will slow down the formation of corrosive deposits. Replace the positive clamp and then the negative clamp. Use a proper sized wrench to tighten them down. Replace the rubber boot or plastic shield that covers the terminal. 

With your battery checked and cleaned, it should last several years and keep your vehicle turning over quickly, your headlights bright, and have you singing along to your favorite tunes on the radio.