The short answer is yes, your car battery can die while you are driving.
Getting stranded or having to jump your car is stressful.
Learn what steps to take if your car battery dies while you are driving, what causes this, and how you can avoid it in the future.
Dead Battery While Driving: Next Steps
You are driving and you notice a light pop up on your dashboard warning you about your battery.
If your car battery dies mid-trip but your alternator is functioning properly, your engine will keep running, but not for long.
At first sight of a battery warning light, pull over to a safe location off of the road.
To preserve energy on the way, turn off any components of your car that use a lot of electrical power—including the radio and air conditioning.
You should be able to reach a safe location easily because your car can function on the alternator alone.
However, the alternator works best solo when the car is moving.
Once you turn your car off, you likely won’t be able to start it again. At this point, you can try jumping the battery or calling roadside assistance.
Bad Battery and Alternator
In the event that your battery dies AND the alternator fails, your car will immediately stop running, likely after a few sputters.
This feels similar to stalling a stick-shift car.
In addition to the engine turning off, so will all other functions of your car that require electricity, including:
- Power steering.
- Dash cam.
In this event, set up the roadside flares—which often can be found in your emergency bag.
If you don’t have flares, it is important to exit your car and walk far away from it.
If it’s dark out, there is no way for passing cars to see you since your lights are off.
In addition to that, your airbags won’t go off if somebody does accidentally swipe your car. Once you are in a safe spot, call for roadside assistance.
You’ll need to tow your car and get it repaired. Find out how much towing costs per mile.
Top Causes of a Dead Battery While Running
Your car needs a properly functioning battery and alternator to generate enough power to run.
If your battery gets fully depleted mid-trip, that’s a sign the electrical system is malfunctioning.
This malfunction is most commonly caused by the alternator.
Your car’s alternator generates power for the electrical system by converting energy from the car’s crankshaft into electricity.
External and internal malfunctions of the alternator are possible.
External malfunctions are most common and can be easily diagnosed with a quick look at the alternator, as the drive belt would be loose or broken. This can be solved with the quick fix of a new drive belt.
On the other hand, if an inspection reveals the drive belt is not altered, there may be an issue with an internal piece of the alternator—for example, malfunctioning voltage regulators or grimy electrical connections.
Because this is a much more complex task than repairing an external component of the alternator, it is best to seek professional help.
Learn how much it can cost to replace a bad alternator.
Alternatively, if your car battery dies but the alternator is intact, that indicates an issue with the battery itself.
If your battery is damaged or faulty, the alternator will not be able to charge it.
A visual inspection of the battery and a battery test conducted by a professional can solve this.
Find out how much you can expect to pay for a new battery if yours is bad.
Prevent Your Battery Dying While Driving
The best way to avoid your car’s battery dying while you are driving is to keep a close watch on warning signs that it’s time to replace either the battery or the alternator.
Signs Your Need to Replace Your Car’s Battery
Pay attention to the following signs, because they indicate it’s time to get a new car battery:
- Your car won’t start.
- Your check engine light is on.
- Your car stalls.
- Your engine turns over 3+ times when you are starting your car.
- You need to jump start your car several times a week.
- Your engine has trouble starting when it’s cold outside.
- Your interior lights look more dim than usual, or don’t turn on at all.
- Your exterior lights flash, look more dim than usual, or don’t turn on at all.
- Your radio has weaker signal than usual or sometimes doesn’t turn on at all.
- Your battery 5+ years old.
Signs Your Need to Replace Your Car’s Alternator
If your battery appears to be healthy, yet it is frequently getting drained, this is likely because the alternator is unable to charge it.
This is important to diagnose because repeatedly jumping a good battery will damage it and repeatedly replacing good batteries is a waste of money.
The following signs indicate it is time to replace your car’s alternator:
- Your car’s engine turns repeatedly when you try to start it.
- Dim interior lights.
- Dim radio lights.
- Dim headlights.
- Dim tail lights.
- Accessory lights flash when you accelerate.
- Unusual smells.
- Odd sounds.
The battery relies on the alternator and charging system to maintain enough charge to start and power your vehicle. Learn more about how long it takes to charge a car battery.
If your car won’t start, a bad starter motor could also be the culprit.