Have you asked yourself if can you jumpstart a car with a bad alternator? Well, if this is the case, and supposedly you have this problem, we would be happy to answer all of your questions and help you overcome it.
- Car Battery
- Bad Battery Symptoms
- Bad Alternator Symptoms
- How To Test Them?
- How To Jump?
Having a problem like this can be a real pain to deal with. Imagine that your battery is all empty and the alternator doesn’t charge. What can you do in these situations? I bet that there will be a ton of questions that will come to your mind and ideas about what you can do in these cases.
Some of them will be good and some of them will be bad. The important thing is that you are here because we are going to share with you all the essentials when it comes to the question of can you jumpstart a car with a bad alternator.
First, we are going to learn what is a car battery and what is an alternator. Knowing this stuff is key for beginners especially to help them understand how these two components work. Then we are going to cover the bad battery symptoms and bad alternator symptoms.
Later on, we are going to discuss more on how to diagnose a dead alternator and lastly, we will cover if can you jumpstart a car with a bad alternator (otherwise, do you need to learn how to know if alternator is bad). So, if you want to learn more, follow along.
What Is A Car Battery (And Can You Jumpstart A Car With A Bad Alternator)?
Now before we dive into explaining if can you jumpstart a car with a bad alternator. Let’s learn more about what is a car battery in general. Knowing what this component is and what is its method of action is really important when it comes to tackling problems like these. This is why we need to explain how this component works and what is its method of action.
So, what is a car battery? A car battery, in simple words, is storage for electricity that will store enough power for you to power the accessories in your car for a while and also help you start the engine.
Modern car batteries are not that modern. Even though there are modern designs such as lithium-ion batteries and AGM batteries. Most of the batteries used out there is the flooded type of batteries.
These batteries are also known as lead-acid batteries. They basically have lead plates that are submerged in sulfuric acid. And then through a chemical process, the battery is recharged. And this design along with some other components such as the spark plugs, and starter motor has not changed a lot during all these years.
A good battery with a good alternator should produce about 12.6 volts. When charged a battery should have between 13.7 to 14.7 volts. But can you jumpstart a car with a bad alternator? We will get to that in a bit.
What Is An Alternator (And Can You Jumpstart A Car With A Bad Alternator)?
Now before we jump into the topic of whether can you jumpstart a car with a bad alternator, let’s first learn more about what an alternator really is. Knowing this will be really useful when it comes to the diagnosing process and determining whether the alternator or the battery is bad. So, let’s begin.
An alternator in simple words is an electric generator. This generator is creating electricity, more precisely alternating current known as AC current. Then this current is converted and the alternator is outputting a direct current known as DC current.
So, whenever you try to measure the voltage on something like a car battery or another component, you always measure DC volts.
This alternator generates enough electricity to power up all the accessories and also run the engine as it should. And a lot of components need a constant power supply in order so the engine keeps working. More precisely the ignition coils and spark plugs.
If the alternator is not in the best shape, the spark plugs will start to draw current from the battery. And you will be left with an empty battery really fast. But more on this, we are going to elaborate later on when we are going to answer the question of whether can you jumpstart a car battery with a bad alternator.
What is important for you is to learn if this alternator is producing enough power. A good output when the alternator is working should be somewhere between 13.7 and 14.7 volts.
Also, later on, we are going to learn how you can measure the output of the alternator. Now let’s move on to the bad battery symptoms and then we will see if can you jumpstart a car with a bad alternator.
Bad Battery Symptoms
Now before we learn if can you jumpstart a car with a bad alternator, let’s take a look at the bad battery symptoms. What could indicate that you have a bad battery in your vehicle?
Knowing these symptoms will help you to tell if you are dealing with a bad car battery or a bad alternator. So, let’s begin covering them.
1. Battery Light On In Car
The first symptom of a bad battery that we are going to cover before we dive into the topic if can you jumpstart a car with a bad alternator is the battery light (or, the Honda Odyssey battery light).
Whenever you are dealing with a bad battery or a bad alternator, you will notice the battery light on the cluster (aka the battery symbol on your car). This light is an indication that you have a problem with the battery holding charge or the alternator not being able to charge the battery. Now let’s move on to the next symptom.
2. Car Doesn’t Want To Start
The next symptom of a bad car battery that we would want to cover before we learn if can you jumpstart a car with a bad alternator is the inability of the car to start.
This symptom will be noticeable when the battery doesn’t have enough charge. In most cases, it will crank but will not be able to start. And in extreme cases, the battery will not be able to crank the engine at all.
In these situations, you will notice a clicking sound from the starter and that would be it. A clear sign of an empty battery or a bad starter (which you can verify if you learn how to tell if starter is bad, and get your car going again by learning how to jump a starter).
3. Car Struggles To Start But Runs Fine
The next symptom that we are going to cover before we learn if can you jumpstart a car with a bad alternator is the situation when the car struggles to start but runs fine.
This problem is mostly caused by a battery that has at least one dead cell. There are six cells in total that can hold 2v of power. So, if you have a situation like this you have maybe 1 dead cell and your battery level is low but enough to start the engine.
This is clear information that you need to inspect the battery and see how much charge it holds. If it holds about 10v it means that one cell is dead.
4. Car Won’t Start But Radio Works
Another symptom that we are going to cover is when a car won’t start but the radio works. This is also a good example of a weak battery. Especially if the battery has two dead cells in it. In this case, you might be asking the question of if can you jumpstart a car with a bad alternator. But problems sometimes lie in the battery itself.
If there are two dead cells, it means that the battery has 8v of power. Enough to power the radio but not enough to start the engine. Now let’s move on to the bad alternator symptoms.
Bad Alternator Symptoms
Now as we covered the bad car battery symptoms. We think that now it is time to cover the bad alternator symptoms as well. They are also crucial to know when it comes to the question if can you jumpstart a car with a bad alternator.
You need to learn these symptoms before you move on to understand the problem and if can you jumpstart a car with a bad alternator. The first symptom is the battery light we are not going to cover since we elaborated more on this in the previous chapters. Now let’s get into the symptoms.
1. Bad Alternator Sound
Now let’s cover the first symptom in our list of bad alternator symptoms. Before we dive into answering the question of whether can you jumpstart a car with a bad alternator.
This symptom is audible information that you have a problem with your alternator. Whenever this component is going bad, it will start to produce strange sounds. These sounds can resemble whining when the engine starts or even grinding in worst cases.
The development of these sounds is mostly connected to the bad bearings inside of the alternator. Inside there is a shaft and bearings. These bearings wear out and the shaft starts to lose balance. Once this is the case, the shaft will wobble around and produce bad alternator noises.
2. Car Dies While Driving
Another in our list of bad alternator symptoms is the symptom when the car dies while driving. This symptom will make you question if can you jumpstart a car with a bad alternator that’s for sure.
Nobody wants this situation happening to them but sometimes it can happen. The alternator could die and once the alternator is dead, your engine will simply shut off completely.
Then you will not be able to start this vehicle unless you jump start it or switch a new battery to it. And performing this in the middle of nowhere is really difficult. Unless you find someone to help you jump start your engine with their car.
And later on in the article, we are going to cover precisely this where we will learn more about how can you jumpstart a car with a bad alternator. But for now, let’s move to the next symptom.
3. Car Battery Keeps Dying
Another sign that could indicate a bad alternator is the situation when the car battery keeps dying. The car battery will keep dying unless you learn if can you jumpstart a car with a bad alternator.
The alternator needs to produce enough voltage to keep the battery charged and that is about 13.7 volts on idle. So, if the voltage is below this, the alternator will not charge the battery enough to meet the threshold value of about 12.6v.
In this case, the battery will lose juice and you will end up with a completely empty battery and a dead car in the process. So, you understand why you need to learn if can you jumpstart a car with a bad alternator.
4. Car Won’t Start With Jump Due To A Bad Alternator
The next symptom of a bad alternator is when the car won’t start with a jump. We are going to explain later on if can you jumpstart a car with a bad alternator. This is possible.
But whenever you cannot start a car with a jump, it means that you are doing something wrong and you are not following some of the steps involved in this work.
Later on, we will dive into all of the steps necessary for you to understand how you can jumpstart a car with a bad alternator. So, you don’t want to miss that. Now let’s move on to the next symptom.
5. Car Turns Off While Driving But Turns Back On
Another symptom in our list of bad alternator symptoms is when the car turns off while driving but turns back on. So, why is this the case?
Well, this could be the case because your alternator could not produce enough energy to meet the demand.
So, the engine could simply shut itself down, and then when you crank it to start as if nothing happened. This is not a good thing because you may once be lucky and your car will start. But eventually, the car will die completely and the only way to start it will be to learn if can you jumpstart a car with a bad alternator. But more on this in a bit.
6. Car Won’t Start With New Battery
And the last symptom that we are going to cover is when the car won’t start with a new battery. This should not be the case actually if the battery is full and it is the first time that you are connecting it to the car.
But if you ran the new battery for a while and the alternator is not charging it. The battery will get empty eventually and will prevent your car from starting. So, be aware of this because no matter how strong of a battery you have, if the alternator is not charging, you will lose the ability to start the car.
But how you can test a battery and an alternator to determine what could be wrong? This is also a very important thing to note before you learn if can you jumpstart a car with a bad alternator. And that’s what we are going to cover next.
How Can You Test Them (And Can You Jumpstart A Car With A Bad Alternator)?
Now as we learned what are the battery and the alternator. As well as the symptoms that they produce. We think that now it is time to cover how can you test an alternator. Knowing this will help you diagnose a bad alternator. Then we are going to cover how you can jumpstart a car with a bad battery and how is this possible. So, follow along.
How you can test a battery and an alternator? Well, it is really easy. The only tool you will need is a multimeter. With the multimeter, you will be able to measure some of the properties of the car battery. Which in our case is the voltage.
So, you will need to tweak the multimeter to DC volts and then put the black probe to the ground wire and the red probe to the positive terminal.
A good reading for a healthy battery should be 12.6 volts. Anything below this could indicate bad charging ability of the alternator or possibly a dead cell of the battery if you are missing 2v let’s say. These measurements like 8v or 10v can easily tell you that one or two cells of the battery are dead and this battery needs to be replaced.
Then to check the alternator, you need to start the car and leave the probes on. A good charging alternator should be producing between 13.7 and 14.7 volts. If this voltage is higher than 15 volts your alternator probably has a faulty voltage regulator. Driving like this is really dangerous because this could cause a fire. So, beware of this.
Overall, that’s all when it comes to diagnosing a bad alternator. But how can you jumpstart a car with a bad alternator? Let’s see more about that next.
Can You Jumpstart A Car With A Bad Alternator
Now let’s get to business and learn more about how can you jumpstart a car with a bad alternator. Is this possible and how it is done?
To answer this short, yes it is possible to do. But it is worth noting that will not take long before your car shuts off again. This is the case because the car needs constant energy generation. The battery is a limited supply source of power.
You need an alternator in good working order so your car does not shut off after half an hour or so. But how this procedure is done? Let’s explain.
In order to jumpstart a car with a bad alternator, you will need another car with a healthy battery. Then you will need to connect the jumper cables with your terminals and the terminals from the other car. Attach the red cable to the positive terminals and the black cable to the negative terminals.
Then start the engine and let the car charge the battery that you want to jump. Wait between 10 to 15 minutes until the empty battery is fully charged.
The last step will be to start the engine on the car with a bad alternator. The engine should run fine, even with a dead alternator. But as we said, the car will run until the battery gets empty. This could last for 5, 10, or 15 minutes.
Then if the alternator is dead and is not charging, the car again will shut down the engine. Now let’s conclude this article.
Conclusion To Can You Jumpstart A Car With A Bad Alternator
In this article, we have covered quite a bit when it comes to the problem with starting up your car. First, we learned what the battery and the alternator are and how they work.
Then we have covered both battery and alternator and the symptoms they produce when they go bad. After that, we learned how you can diagnose a bad alternator and also if can you jumpstart a car with a bad alternator. Which is yes but driving like this is not recommended.
F.A.Q To Can You Jumpstart A Car With A Bad Alternator
Now let’s answer some frequently asked questions.
Why Does My Car Battery Keep Dying
The car battery keeps dying because of a faulty alternator. The alternator is a key component that serves the purpose to charge the car battery. So, whenever this component fails to deliver the demanded charge. Your battery will be empty all the time. Sometimes it will eventually die and you will not be able to start the car. Unless, if you can jump-start a car with a bad alternator.
How To Jumpstart A Car
In order to do this, you will need another car and a set of jumper cables. Then you just connect the black cable to the negative terminals and the red one to the positive terminals. Start the car and then you will be able to jump-start the other car with the dead battery.
How Long Does It Take To Jump A Car
Usually takes between 10 to 15 minutes depending much on how experienced you are with using jumper cables. The more you understand this procedure the quicker you will be able to finish it and hopefully sort out your problem.
What Causes An Alternator To Go Bad
Usually, the bearings inside of the alternator fail. The bearings fail and the shaft is losing the balance. Once the balance is lost the alternator is not performing as it should and has to be rebuilt in order to resume the work.
How To Test Alternator
You can test an alternator with a multimeter. Get a multimeter and turn it to measure DC voltage. Then place the black probe on the negative and the red probe on the positive terminal. Then start the engine. A good alternator should produce a voltage in the range of 13.7 to 14.7 volts.
How Much Is A New Alternator
A new alternator usually costs about $250 for most cars. This price is only for the part. The labor is also extra and could cost you about $100. So, a new alternator could cost you about $350 in total.