How to Change a Car Battery

Changing a Car Battery Tips

If you’re noticing that your car is a little slow to start or it’s been seven years since you last replaced your battery, it might be time to get a new one. However, since your car’s electrical system is more complicated than just the battery, it’s important to check other components as well and do some self-diagnosis of other areas before determining the battery needs replacing.

Please watch the following video and then read the rest of the article.


Make Sure The Problem Is Really the Battery

First, look for sulfate buildup around the battery terminals, which will appear as a white-blue powder. When you clean this with some battery terminal cleaner, it may help your battery work again because the buildup of that residue is preventing it from receiving a clean electrical signal. The residue adds resistance.

Here are a few signs the battery is dead:

  • When you try to start the car, the engine doesn’t turn over, and instead there’s a low whining sound (or you hear nothing at all)
  • If you’re successful at jumpstarting the car, but once you park and turn it off, it won’t start again, the problem is likely caused by a dead battery. The alternator, in this case, is helping it hold a charge while the car is running, but the battery can’t hold a charge once the alternator is off.

Check the Alternator

The alternator is responsible for maintaining the battery’s charge while the car is running. It should maintain a charge close to 13.8 – 14.2 volts in a charging system that’s functioning properly. The battery, on the other hand, should be hovering somewhere around 12 volts (12.4 – 12.8) when the car’s not running and with no accessory load.

Signs the alternator has failed include:

  • A growling sound is often heard before the alternator goes out.
  • If it’s overheating, you can smell burning rubber or hot electronics
  • Headlights may dim, flicker, or get extra bright when the car is moving fast.
  • Gauges on the dashboard are behaving strangely
  • If the car is jump started and it does start, but then the engine dies again right after the jump, it’s likely the alternator that’s the problem.

Once you’ve determined the battery is actually the problem, you can go about replacing it. You’ll need to know the kind of battery you’re replacing as well as your car’s make, model and engine size. You want to buy one that’s going to be compatible with the battery tray in your vehicle.

Replacing the Battery

First, make sure your car is parked on a level surface, away from any sources of spark or flame. Use gloves to protect yourself from sulfuric acid potentially getting on your skin. Open the hood of your vehicle, and remove the old battery.

Identify the positive and negative cables first—the positive cable is typically red and will have a plus sign (+) printed on it, while the negative cable is usually black and will have a minus sign (-) printed on it.

Disconnect the negative cable first, by loosening the bolt with a wrench or socket wrench. A typical size is 8mm or 10mm, depending on the make and model of the vehicle. Then, disconnect the positive cable. Make sure the positive cable and negative cable don’t touch, or it could potentially short out the electrical system.

Now, remove the old battery from the vehicle’s tray. Batteries are heavy, and can weigh between 30 and 60 pounds, so you might need some help lifting it.

Before installing the new battery, you’ll want to clean the battery terminal clamps. A wire brush and baking soda solution should do the trick. Now, install the new battery, making sure the positive and negative terminals are on the correct sides. Reconnect the positive terminal first, using the same wrench you used earlier to tighten the clamp. Now, reconnect the negative terminal and tighten that too.

Use lithium grease to spray the battery terminals once you’ve finished installing it. This will help prevent future corrosion. Attempt to start your car with the new battery, and make sure that all electronic gadgets work properly.

Proper Disposal

You’ll want to dispose of your old battery using the right methods. Many local auto shops will take your old battery and recycle it, as well as other retail stores that sell batteries. They may charge you a small fee for the service, but this is to cover the cost of proper disposal. You should never put a battery in the garbage, this is environmentally dangerous and irresponsible.

Hopefully this guide was helpful so you can replace your battery safely. Your new battery should last anywhere between 5-7 years as long as corrosion doesn’t build up excessively. Check the terminals from time to time, such as when you change your oil.

Leave a Reply

Your email address will not be published.