5 Simple Ways to Tell if Your Car Battery is Really Dead

There comes a point in your vehicle's life when its battery gives out on you and then goes completely dead.

There are many reasons why this can happen. For one, it just might be old. Experts say that the average life span of a car battery can reach five years in an ideal setting. If your battery is older than that, then it just might be reaching it final stages before it croaks.

Other reasons why car batteries die may include the following:

• You left your car's audio system or interior lights on for a long time.
• Your alternator is malfunctioning.
• You bought low-quality batteries.
• You're an accessories hog.
• Your battery’s upper half lacks acid that causes it to drain faster. This happens when the electrolytes pool at the bottom.
• You charge it the wrong way.

There are signs that will tell you if your battery is dead; the trick here is to see if many--or all these "symptoms"--can be applied to your situation. The more checks you have, the stronger it indicates that your battery has gone to its final, resting place. Here are the signs to watch out for:

1. All the accessories are not working properly.

Check your radio, your power doors and windows, headlights, wipers, lights, and speakers. Are they all dead? These accessories need power from a car battery to function, so if they're not working (or they're dimmer and slower than normal), then the culprit might be a dead battery.

There are some cases where you might encounter some accessories that are working--and some that aren't. If that's the case, then chances are it's not a dead battery you're dealing with.

2. Focus on the car horn first, not the lights.

Speaking of accessories, look--and listen--closely at your car horn. They use a lot of power--much more than your vehicle's headlights.

When you're horn isn't working, then there's a good chance that your battery is about to die--or is already dead. So worry more when your horn's not working than when you encounter flickering headlights from time to time.

3. And then there’s that smell.

Can you smell something foul—like a burning, rotten egg near the hood? That smell is sulfuric acid. Most conventional acid-lead automotive batteries are filled with a blend of sulfuric acid and water. Once a battery nears its end, some of the acid and water evaporate, and cause the battery to overheat or boil down. This produces that malodorous "rotten egg" smell.

4. Listen for that "clicking" noise

You're probably familiar with the sound your car makes when you turn your ignition on. So chances are, you can notice subtle changes in sound that might indicate that there's something wrong with your vehicle.

Try turning the ignition on. You should hear the engine crank—or chime a bit. However, if the battery is dead, then you'll only hear a clicking noise. Once this happens, try jumpstarting your battery to see if you can revive it. If it dies on you again after the initial jump, then chances are it's reached its final end.

5. Your battery tester says it's dead.

When all else fails, the best and most reliable thing to do is to just use a good battery tester and see if it's dead. This is the most accurate way to know if there's still hope for your battery--or when it's time to throw in the towel and buy a new one for your vehicle, instead.