Nobody likes that sinking feeling of turning a key and getting no response. Whether you’re late for work or stranded in a dark parking lot at night, a dead car battery can ruin your entire day. But how can you tell if your car battery is dead or if something else is making your car not start up.
In this blog, we’re going to go over how to know if a car battery is dead, the most common dead car battery symptoms and how to diagnose your car battery before just replacing it. By the end, you’ll be able to spot the early warnings and take action before you get left in the lurch.
Why to Know Matters & How to Recognize a Dead Car Battery
Car batteries typically don’t die without one or more signs of trouble. In fact, many drivers could prevent sudden battery issues if they recognized the symptoms of a dead car battery. Knowing how to tell if your car battery is dead can also help you plan ahead to avoid towing fees — and can extend the life of your battery by catching the problem in time.
The first question that typically crops up when the car won’t start: Is the battery dead? Or could it be something else, such as the alternator or starter?
But before you make accusations, search for signs of a dead car battery. Some are obvious — like total power failure, and others are less so. It’s easier to prevent larger problems further down the road if you spot the symptoms early.
Common Signs Your Car Battery Is Dead
If you’re asking yourself, how do I know if my battery is dead, you’ll want to begin by knowing what the tell-tale signs are. The following are the most frequently-asked questions on how to tell if car battery is dead:
Engine Won’t Start
The clearest indicator your battery is dead is when you turn your key and the engine doesn’t start, or the engine doesn’t do anything altogether aside from hearing a fast clicking noise. This clicking occurs because the starter motor is not receiving power to crank the engine.
If you are asking yourself how do I know if my battery is dead, this is usually the first and most reliable indicator.
Dim or Flickering Lights
Your battery does more than just feed the engine; it also supplies juice for your lights and electronics. Dim headlights or dashboard lights that start to flicker when you turn the key is a strong indicator of this classic dead car battery symptom.
So if you’re wondering “how can you tell if a battery is dead?” — look at your headlights. If they tattle-taling barely light up, or fade to nothing when you crank the ignition, the battery is likely the culprit.
Electrical Accessories Not Working
Another method where you can tell if my car battery is dead, is if your power windows, stereo, or wipers are slow to operate. When the voltage in the battery gets too low, all of these systems go haywire.
Battery Warning Light
Dashboards typically have a warning light in the shape of a battery. If you notice this light lighting up while you’re driving or even when you’re trying to start your car, this means your battery doesn’t charge as intended or it has a serious fault.
How do you know if your car battery or the alternator is dead? If the car cranked up but the battery light is on, you may have an alternator problem. But if the car refuses to start entirely, the battery is likely completely depleted.
Swollen Battery Case
Overcharging and heat may cause the battery case to swell, or even bulge. If you lift the hood and find a battery that appears swollen, chances are it’s damaged beyond salvaging.
This is an extremely obvious dead car battery sign and it tells you that you’ve got to change your battery right away. It is not safe using an swollen battery.
Rotten Egg Smell
One of the bad smelling signs of a dead car battery is powerful sulfur smell. That occurs when battery acid leaks into the atmosphere and releases a hydrogen sulfide gas that could be reminiscent of a rotten egg.
If you smell this, don’t ignore it. It can also cause nearby parts to corrode and may even present a safety issue.
How to Check If Your Battery Is Truly Dead
If you recognize any of those more visible signs and are still asking yourself how to know if car battery is dead, then it’s time to test your battery. Here’s how:
Use a Multimeter
You can buy a multimeter from any auto parts store for a few dollars. Here’s how to measure your battery voltage:
- Take a multimeter and set it on the DC voltage mode.
- Place the red lead on the positive (+) side and the black lead on the negative (-) side.
- When fully charged, a good battery will read over 12.6 volts.
- If it’s below 12.4 volts, it is low.
- Less than 12 volts typically means the battery is heavily discharged or dead.
If you were asking how to determine if the battery is dead, a reading of less than 12 volts is the answer.
Try Jump-Starting
Another fast way to know how to tell if a car battery is dead is to try a jump start:
- Hook jumper cables to another running car.
- Let it charge for couple minutes.
- Try to start your car.
If it starts, your battery was running down, but there could be enough of a charge left to start your vehicle. If it doesn’t, you may have a dead battery, or another issue that is preventing the vehicle from starting, such as a faulty starter or alternator.
Professional Battery Testing
Battery testing is provided free at most auto parts stores. They’ll also use a load tester that subjects your battery to the stress of starting your engine in order to test that.
This is by far one the best methods to know your car battery is dead for sure.
Other Causes of Starting Problems (Not the Battery)
At times, what appears to be a dead battery is something else. If it is beyond the battery, consider these possibilities:
Bad Alternator: Without a charge from the alternator, even a new battery will die.
Bad Starter Motor: A clicking sound could also indicate a starter that has worn out.
Neglecting the Battery Terminals: Corroded or loose terminals will no longer allow electricity pass through them.
Parasitic Draw: Electronics can draw on the battery overnight if they are left on.
If you’re still left wondering, how do you know if car battery is dead vs. a different problem, a mechanic is able to diagnose the specific problem.
Conclusion
A dead car battery need not be the end of the world. Once you know the early warning signs — dim headlights, slow cranking and such, you can act before you end up getting stranded. From jump starts, to battery replacements, to even full roadside assistance, it’s always a great idea to have a reliable team at the ready.
If you have a dead car battery or you’re uncertain of whether it’s time to replace your car battery, we got you covered at All 4 One Transportation to ensure that you’re not ever stranded for long. Add to that the fast, professional service, and you can get back on the road quickly and safely. Proudly serving Allenhurst, GA and the surrounding area with 24/7 service.
FA
The average lifespan of most car batteries is 3–5 years, though the type and condition of the battery, the climate, and driving habits can all have an impact.
Sometimes, although deeply discharged batteries frequently should have lost capacity and be replaced.
My suggestion is to have a mechanic do the due diligence on the charging system and check for parasitic drains.
