A car’s battery not only starts the engine but also powers electrical components, like headlights. When these lights start to dim or flicker, it could be a sign that the battery is dying.
White or bluish corrosion around the battery terminals restricts power flow and signals internal degradation. A sulfur smell — akin to rotten eggs — is another clear indicator that your battery is leaking.
1. Your Engine Won’t Start
It’s never convenient when your car refuses to start. It’s even worse when you’re stranded with a dead battery and nobody nearby to jump your vehicle. You should always keep a set of jumper cables in your trunk and a portable car battery charger. Alternatively, you can also flag down a friend or fellow driver willing to lend you their battery.
There are several reasons why your engine may crank but not start. It could be an issue with the ignition, your alternator, or a bad battery. If you open the hood of your car and notice that the battery seems swollen, it could be leaking battery acid. The acid creates a smell like rotten eggs, which isn’t pleasant to be around. A new battery should fix this problem.
2. Your Headlights Don’t Illuminate
If your headlights aren’t as bright as they used to be, this could be a sign that your battery is starting to fail. This is because a weak battery wreaks havoc on other electrical components of your car, including your headlights.
Another reason why your headlights might not be as bright is because the bulbs are burning out. This can happen if you drive for Uber or Lyft, or if you frequently use your vehicle for delivery work. You can test this by taking a known-good ignitor module and connecting it to the socket of the headlight that’s burned out. If this fixes the problem, it means that the original ignitor module is bad. A mechanic can help you replace it. They may also recommend a new wiring harness or a replacement fuse.
3. Your Radio Doesn’t Work
If your radio isn’t working, this could be a sign of a dead battery. Batteries don’t last forever, and as they start to wear down, they produce hydrogen sulfide gas which smells somewhere between rotten eggs and sewer water. This sulfide is a surefire way to know your battery is dying, and a bulge or swell in the case can also indicate it’s about to die.
If you feel jolts or hitches when driving that fade away within a minute, it could be a sign of a weak battery. Your car is designed with specific demands in mind, and your battery should be able to meet them. When it can’t, it’s time to replace it. You might notice general electrical problems as your battery dies, including a sunroof that suddenly doesn’t open or dashboard lights that flicker.
4. Your Tires Don’t Shine
If your car’s tires don’t shine or seem to lose their brightness, it could be a sign that your battery isn’t charging properly. A dying lead battery produces hydrogen sulfide gas, which has a distinct odor that’s somewhere between rotten eggs and sewer water. If your battery is leaking sulfur or you’re noticing the smell, it’s time to replace it.
A new battery will last longer than an old one, but every battery has a finite lifespan and even the best batteries have a limit. A quick test at a local auto parts store should tell you without a doubt if your battery is dead or on its way out.
5. Your Alternator Isn’t Working
Every battery has a finite lifespan, and while proper maintenance, avoiding temperature extremes and short trips, and using less electronics can extend it, you’re bound to have to replace your battery eventually. It’s important to recognize the signs of a bad battery or alternator so you can get it replaced before it runs out and leaves you stranded in a dangerous place.
A dead battery will have a distinct, rotten egg smell, stemming from sulfuric acid that vented out as the battery died. You might also notice that your battery appears swollen, which is caused by liquid leaking from the terminals. A professional inspection can pinpoint the issue and help you choose a replacement. It’s worth it to avoid being stranded without a working car.
6. Your Tires Are Worn Out
Although proper maintenance and avoiding driving on rough roads can extend battery life, every standard car battery will die at some point. A dying battery will not only fail to start your engine, but it may also prevent other vital electrical components from working correctly. When a vehicle’s lights flicker or appear dimmer than usual, it could be a sign that the battery isn’t holding a charge anymore.
Abrupt turns, quick lane changes and accelerating too quickly can all cause premature wear on your tires. In addition, if you’re constantly jumping your car, that can cause the batteries and starter to wear out faster than they should. Recognizing these warning signs and addressing them sooner rather than later can save you time, money and unnecessary stress.
7. You’re Not Getting Any Power
Many people don’t know that their battery’s dying until they try to start their car and it doesn’t turn over. That’s because warm temperatures, routine driving and a healthy engine can mask a weak battery’s gradual decline.
The way a battery’s strength is measured is in cold cranking amps (CCA). Every car needs a specific CCA to start. If your battery is low on CCA or its label shows it’s not delivering that power anymore, it’s time to get a new one.
Getting your battery tested regularly is just as important as getting your oil changed or having your brakes checked. It can help you avoid being surprised by a dead battery when it’s least convenient. To test your battery, use a voltmeter and leave everything off that might draw power. A healthy battery should show about 12.6 Volts.
