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So if you were wondering what a car alternator is, and how a car alternator works? and what are its functions etc. then this is a right place to get a quick overview of everything.

The car is not just a mode of locomotion from one place to another. It is also a place of comfort while you travel. So there are a lot of other electric auto parts and accessories functioning apart from the wheels and the engine. 

The electrical parts have an important role in any car. Now, with the cars of the new generation the dependability of cars on electronic parts has increased significantly.

The battery does provide the support to the electrical system in the car but it is insufficient. And moreover the circular (motion) energy which moves the vehicle from one place to another could be further utilised to generate electricity.

This is where the alternator comes into play. The alternator of the car is used to generate electricity and provide electricity to the complete electrical and electronics parts in the car such as the headlights, tail lights, the Air condition, the radio and other such appliances. The electrical energy generated is also used to recharge the battery of the car.

In this article you will learn about the alternator of the car and its impact on the electrical and electronic systems, along with working and the signs of bad alternator and ways to increase the life of an alternator.


A Brief History about the Car Alternator

The first ever alternator was invented by French scientist Hippolyte Pixii in 1832. But this was the very basic design of the alternator. It was not convenient to use this alternator in the car, because of some problems. One of the problems was the management of the electric current that reversed its direction. This was temporarily resolved by creating a commutator. The commutator only produced direct current (DC), so there was no question about the reverse current.

Until the 1960s, cars just used DC dynamo generators with commutators.

The alternators were first used in cars produced by Chrysler corporation. Ford and general motors were late in adapting the alternators in their car designing and planning.

Function of a car alternator

The car alternator is responsible for generating electricity and distributing it to the different electrical and electronic systems inside the car. The car alternator also recharges the electric battery.

How Does a Car Alternator Work?

The working of an alternator is based around the idea of conversion of mechanical energy into electrical energy. When the engine is working, it creates a rotatory (circular) motion. This circular motions mainly helps the power train of the car but this also powers the drive belt which is attached to the alternator. 

Inside the alternator there is a set of magnets around a stationary coil. The belt rotates the rotor shaft of the alternator which is connected with the magnets. When there is interaction between magnets and the coils the electricity is generated.

Signs of a faulty alternator

signs of a faulty alternator

Here are some of the signs  of a faulty alternator.

1. Dim Lights As a Sign Of a faulty alternator

If your alternator is not in a proper working condition the impact will be on all the electrical appliances in your car. The headlights and the tail lights of the car will be Dim. So the Dim lights are one of the clear signs that there is a problem in the alternator.

2. Problems or malfunction in electronic accessories

If the alternator is not in working condition it means that the electricity generated will not be sufficient enough. As mentioned above this has an overall impact on the completed electrical and electronic appliances in your car.

3. Hearing Whining noises from the bonnet

If the alternator is not in working condition it means that the electricity generated will not be sufficient enough. As mentioned above this has an overall impact on the completed electrical and electronic appliances in your car.

4. Dead Battery

The alternator is responsible for recharging the electrical battery. If your battery is dead it could mean one of the two things, either the alternator is not producing enough current to recharge the battery or there is some kind of problem with your car battery.

Just in case you want to know  –> How to increase the life of your car battery

5. Trouble in self starting of the car

If your car battery is not working properly, this has a direct impact on the self starting system of the car. If there is a problem in self-starting the car, it is one of the signs of a bad alternator.

6. Burning odour from the car

If there is a problem in the alternator of the car. The excess heat will result in a burning smell in your car. The alternator already has to work in a very high temperature environment. When there is a problem this immediately results in a burning smell.

7. Battery warning light on the engine dashboard

When there is a warning light on the dashboard of the engine, against the battery light it means there is some problem with either the battery of the alternator. If you see the battery warning light is on it could be a sign of an alternator problem.

How long does an alternator normally last?

Normally the lifespan of an alternator is around four to eight years. This depends on how long the car is driven. It also depends on the internal hygiene of the engine system and the regular operations. It also depends on the quality of auto spare parts used. It also depends on the electrical system and use in a particular car.

How to extend the life of an alternator?

how to increase the life of the alternator

1. Reduce the unnecessary use of Appliances in your car

It is very common to have electric appliances in operating condition even in idle condition of the car. This causes overload on the alternator. Make sure to add only necessary aftermarket electrical appliances to the car.

2. Check for fluid leaks

Check if there are any gasket leaks in the car. If there are leaks, it will cause accumulation of dirt and moreover, it will cause disturbance in the system. This might overall reduce the life of the alternator.

3. Check the belt alignment

As we discussed above, there is a belt connecting the drive with the alternator. If the belt alignment is not accurate, this will cause unnecessary overload on the alternator.

4. Always jump start properly

If there is a problem in connecting the jumper cables while jump starting the car, this will directly cause a major problem with the alternator. It might cause a short-circuit. When such a problem occurs, you might have to directly replace the alternator.

5. Clean battery terminals

The battery terminals, if not cleaned and maintained properly, are prone to rust and corrosion. Having clean battery terminals will smoothen the process of recharging of the battery. This will help in preventing the alternator from overloading.

6. Have proper airflow and clean engine bay

When the alternator is in working condition, this causes high temperature. This happens because of two reasons, one of them is because of close proximity with the engine and its own working operations. So having proper airflow and clean engine bay is helpful in increasing the life of the alternator.

Here are some tips on your car engine maintenance

7. Prevent and check if the bearings are worn out

Busted bearings are the most common problem that causes alternator breakdown. If the bearings are not good, this makes the alternator useless. Because, the magnetic poles interact with the bearings and generate electricity. So please check if the bearings are worn out.

Wrap Up: How does a car alternator work and what you need to know

Alternators play an important role in any car. If you make sure to take proper care of your alternator. The life span will be high. 

In a nutshell, do not overload the alternator and keep the engine bay clean. Make sure that you follow regular scheduled maintenance.

Please ensure that you use quality spare parts in your car, if you want the car to go long term. Else you never know how things would go.

Let us assume for a moment that you own a Nissan patrol and you are planning an off road trip. If you’ve been off-roading, you know how hard the things are going to be for the engine and other parts of the car. In such cases, if you own an alternator from genuine Nissan spare parts, it will serve you for a long time.