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Can You Jump Start a Car With a Bad Alternator? What You Need To Know!

man holding starter cable

Alternators on cars go bad all the time. Unfortunately, a bad alternator can become an expensive fix and one that is necessary for a car’s operation. A car with a bad alternator cannot charge its battery and generate power for the car to function properly. If you have a car that repeatedly goes dead or is experiencing low power, you could have a bad alternator. In order to get the car to a repair shop that can do the necessary repairs, you might need to jump the car to get it going.

Can you jump-start a car with a bad alternator? The quick answer is yes, but there are more things to iron out before you’re in the clear. Will jumping a car with a bad alternator work? Can jumping a car with a bad alternator harm the car’s engine in any way? This article will explore and answer all of these questions.

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What Does It Mean To Jump a Car?

Jumping a car is a process that takes power from a healthy battery and transfers it to a car with a bad battery. The energy transfer from one car to the other allows the ailing car to get started. Usually, once a car gets started the alternator kicks on and begins generating its own power to keep the car running.

Bad batteries are unable to store power, so jumping a car is normally a temporary fix. How does the alternator play into all of this?

car jump start
Image By: Kurbanov Vener, Shutterstock

Jumping On a Bad Alternator

Jumping a car whose alternator is out of commission will work just as well as jumping a car with a good alternator. The energy needed to get the car running will still transfer and unless something is also wrong with the starter, the car will turn over.

However, jumping a car on a bad alternator is only a temporary fix. Without an alternator, a car will slowly drain power from the battery. A car with a bad alternator and a bad battery will only run for a short period of time before running out of electricity yet again.

Jumping a car on a bad alternator will get the car to start but depending on the severity of the problem with the alternator and the battery, the car might not run for very long at all. It should be enough to get the car to a repair shop where a new alternator and battery can be installed thus fixing the problem permanently.

Are There Any Adverse Effects If You Jump a Car With a Bad Alternator?

No. There are no ill effects after jumping a car on a bad alternator. The only thing is the results will likely be temporary. However, no damage or further degradation of the alternator will occur. If you have a bad alternator and need to get your car started, there is no reason not to try and give it a jump to see if you can get the car started.

car engine
Image By: Room98, Shutterstock

How Many Times Can You Jump a Car On a Bad Alternator?

Theoretically, you can jump a car an unlimited number of times on a bad alternator. If the alternator is already dead, you won’t do any more harm by jumping it over and over again. Jumping a battery multiple times will put wear and tear on the battery and could lead to a shorter lifespan of the battery itself.

However, a car might not run very long with a bad alternator. Jumping a car continuously to try and avoid a repair is not a feasible option. Jumping a car with a bad alternator is best to do when you are planning on taking a car to the repair shop. Trying to trust a bad alternator and relying on multiple jumps puts you at greater risk of becoming stranded on the road if your car dies.

charging car battery
Image By: Noey smiley, Shutterstock

What Does The Alternator Do?

The alternator is the part of an engine that generates electricity for the car. A car’s battery provides limited jolts of power to things like the starter to get it going but batteries are not designed to run the engine full time (unless you have an electric car.) Once the car gets going, the alternator takes over and begins creating power for the rest of the electrical systems in the car. The alternator is powered by the combustion engine. A bad alternator cuts off that independent power supply to the car which causes it to lose power and stall.

How Can You Tell The Difference Between a Bad Battery and a Bad Alternator?

When a car goes dead it is hard to tell the difference between a bad battery and a bad alternator. If a battery is dead it simply will not hold a charge. The alternator might be working fine but the power being created by the alternator will not be stored by the battery. Running a car continuously on a bad battery can put wear on the alternator.

If a car won’t start but will start after a jump before going dead again, it is likely simply a bad battery. If a car starts, runs for a while, and then stalls out and loses power then it is probably a bad alternator.

car engine of an orange car
Image Credit: Photoman, Pixabay

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Yes, you can jump a car on a bad alternator. It will have no bad side effects except for possibly not lasting very long. Without an alternator, a car’s engine will not be able to run for very long unless repairs are made. You can jump a car multiple times on a bad alternator if necessary. So if you suspect that your alternator is failing, do not hesitate to give your car a jump so you can get it into the hands of a competent repair person.

Featured Image Credit: Syda Productions, Shutterstock


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