If you suspect your battery might be going bad, you're in the right place. We spoke to two automotive repair specialists about the earliest signs of a weak car battery, which include dim headlights, malfunctioning electrical components, and a slow-starting engine. In this article, we'll go through the full list of signs to look for to diagnose the issue. We'll also talk about what causes a weak car battery and how to tell the symptoms of a bad alternator from battery issues. Read on to learn more!
Signs of a Bad Battery
- Dim headlights, malfunctioning electrical components, and a slow-starting engine are some of the earliest signs of a weak car battery.
- Pop the hood and inspect the battery for additional symptoms like corrosion on the terminals or a swollen or damaged battery case.
- A bad alternator shares similar symptoms with a weak battery, but one tell-tale difference is that a bad alternator also causes rattling and grinding sounds.
Steps
Weak Battery Symptoms
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Dim headlights Headlights (and your car’s other electrical components) are powered directly by the battery. Sudden electrical issues, like dim or flickering headlights, are early signs that your vehicle’s battery is getting weak. [1] X Research source You may notice other electrical issues like:
- Dashboard controls and interior lights falter or stop working
- Power windows (and sunroof) stop working
- Devices won’t charge when you plug them into the port
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Slow-starting engine If you turn the key in the ignition and the engine’s startup is noticeably sluggish, you’re definitely dealing with a weak battery issue. [2] X Research source It might take several times for the engine to finally crank up, or your vehicle might make a low “rurrr rurrrr rurrr” sound and never turn over at all.Advertisement
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Ignition clicking sound If you try to crank your engine and nothing happens, or if you hear a clicking sound but the engine never turns over, it means your battery is already dead or incredibly weak. To get on the road again, change the battery yourself or jumpstart the car so you can get it to a mechanic. [3] X Research source
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Battery terminal corrosion Pop the hood and examine the battery's terminals (the positive and negative caps where it connects to your car). If you see a lot of blue-green powder or a crystal-like substance, you may need a new battery. A little bit of residue can usually be cleaned off , but a lot of corrosion means the battery is leaking acid and needs to be replaced as soon as possible. [4] X Research source
- Wear protective gloves and safety glasses when you’re dealing with battery corrosion. Automotive repair specialist Duston Maynes says, “the residue is battery acid and it can burn your skin. You can clean off the corrosion, but this is generally a sign that your car needs a new battery.”
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Swollen battery case While you have the hood popped, inspect the battery’s exterior casing. If you see any signs of swelling, cracking, or bulging, it means the battery is damaged and weakening, and it needs to be replaced as soon as possible. [5] X Research source
- Keep in mind that a car battery is typically a rectangular shape; if the rectangle looks irregular at all, there’s definitely a battery issue that needs attention.
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Sulfuric smell Leaking battery acid smells distinctly of sulfur. If you smell that infamous rotten egg smell when you’re near your vehicle, the battery is leaking and getting weak. It needs to be replaced fairly quickly so the acid doesn’t drip and corrode other parts of your engine. [6] X Research source
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Frequent jumpstarts If you’ve recently been relying on jumpstarts to get your vehicle on the road, the battery is low and probably can’t hold a charge anymore–it needs to be replaced. This is especially true if the battery is more than 3 years old. [7] X Research source
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Illuminated battery warning light If the battery light on your dashboard lights up, there’s something going on with your car’s electrical system, and one potential culprit is a weak or dying battery. If you see this light along with any of the above-mentioned symptoms, your battery may need to be replaced. [8] X Research source
Expert Q&A
Video
Tips
Expert Interview
Thanks for reading our article! If you’d like to learn more about car batteries, check out our in-depth interview with Duston Maynes .
References
- ↑ https://www.youtube.com/watch?v=Cqn9ax2JWSY&t=171s
- ↑ https://www.defensivedriving.org/dmv-handbook/how-long-do-car-batteries-last/
- ↑ https://www.thetechedvocate.org/diagnosing-a-dead-car-battery/
- ↑ https://www.defensivedriving.org/dmv-handbook/how-long-do-car-batteries-last/
- ↑ https://reliable-auto.com/top-signs-of-a-bad-alternator-and-dead-car-battery/
- ↑ https://www.defensivedriving.org/dmv-handbook/how-long-do-car-batteries-last/
- ↑ https://offroadingpro.com/weak-car-battery-symptoms/
- ↑ https://reliable-auto.com/top-signs-of-a-bad-alternator-and-dead-car-battery/
- ↑ https://offroadingpro.com/weak-car-battery-symptoms/
- ↑ https://www.kbb.com/battery-replacement/
- ↑ https://offroadingpro.com/weak-car-battery-symptoms/
- ↑ https://www.consumerreports.org/cars/car-batteries/how-hot-weather-affects-your-car-battery-what-to-do-about-it-a4527456418/
- ↑ https://www.carcare.org/2020/07/summer-heat-takes-a-toll-on-your-cars-battery/
- ↑ https://www.consumerreports.org/cars/car-batteries/how-hot-weather-affects-your-car-battery-what-to-do-about-it-a4527456418/
- ↑ https://www.consumerreports.org/cars/car-batteries/how-hot-weather-affects-your-car-battery-what-to-do-about-it-a4527456418/
- ↑ https://offroadingpro.com/weak-car-battery-symptoms/