What Is an Alternator?

There are several important parts under the hood of a vehicle that help it run effectively. They include components that help provide electrical power to various systems. Among them is the alternator.

The alternator is a component in a vehicle that converts mechanical energy into electrical energy, providing power to various systems. It works by using a serpentine belt to drive the rotor within the alternator, creating electricity through the movement of magnets. The alternator charges the car battery by converting the alternating current (AC) it produces into direct current (DC) power that the battery can absorb.

Signs of a failing alternator include a weakened battery, dimming lights, problems with electronics, abnormal noises and issues starting the vehicle. Becoming an automotive technician can help provide you with the skills and knowledge to diagnose and repair alternator issues, as well as pursue a career in the automotive industry. Keep reading this guide to learn all about alternators and why they’re important!

How Does an Alternator Work?

The car alternator is responsible for helping provide electrical power to different parts in a vehicle. It differs from a battery, which is a key component that helps start the engine. Once the battery does its job, the alternator takes over to help keep the car running.

So, what does an alternator do? As stated before, the alternator converts mechanical energy into electrical energy. The crankshaft in a vehicle utilizes a serpentine belt, or V-belt, to drive the alternator, which moves the rotor within the alternator at a high speed.

As this rotor spins, electricity is created. There are magnets inside the alternator that allow the AC to convert the mechanical energy generated into electricity. Power gets sent to a voltage regulator that distributes electricity to different parts of the car.

Parts powered by the alternator include a variety of electrical components, from headlights to electric steering and power windows. The alternator also has the task of charging the battery.

How does an alternator charge a battery?

Car batteries operate on DC power, not the AC that alternators produce. Before energy from the alternator can be sent to the battery, it needs to be converted.

Prior to going through a voltage regulator, power gets sent through a diode rectifier that turns it into DC that the battery can absorb. This allows it to recharge.

What does an alternator look like?

Warning Signs of a Failing Alternator

While most alternators are built to last a long time, there are parts in them that can wear out over time. Overuse, heat damage and general wear can diminish the health of an alternator. Without a working alternator, a vehicle can encounter a range of issues.

Here are some indications that your alternator may be starting to fail:

• Weakened battery: Whenever you’re having battery issues, it’s good to also get the alternator checked out. It could be that the alternator is failing and unable to adequately charge your battery.
• Dimming lights: Noticing dimming or flickering headlights? Alternator failure can cause inconsistent voltage, which can cause this to happen.
• Problems with electronics: Another thing to pay attention to is the different accessories in your vehicle that are powered by your alternator. Power windows not working properly or trouble with the radio could mean that the alternator is on the fritz.
• Abnormal noises: Whining or growling sounds coming from under the hood might indicate that the belt controlling the movement of your car alternator is misaligned. Getting strange noises checked out is always a good idea.
• Issues starting the vehicle: When you put your key in the ignition, you shouldn’t have any problems trying to get the engine going. If you hear clicking noises and the engine is cranking a lot before starting, your alternator might be the cause.

It’s a good idea to get your vehicle looked at whenever you’re experiencing anything out of the ordinary to ensure the parts are working properly. The alternator is an important component in your vehicle’s electrical system that you want to keep in good condition!

Alternator FAQs

How does an alternator differ from a generator?

An alternator can only induce an AC current while a generator can produce both an AC and a DC.

What are the signs of a failing alternator in a car?

Weakened battery, dimming lights, problems with electronics, abnormal noises or issues starting the vehicle can be signs of a failing alternator.

Can a car run without an alternator?

A car can’t go far with a broken alternator or without one. This is because the alternator is what charges the car’s battery. Once the battery is used up, without the alternator, the battery will no longer run.

Diagnose Alternator Issues as an Automotive Technician

A great way to improve your skills working on vehicles is to train to become an automotive technician. Not only could you learn how to maintain and work on your own vehicle, but you could work toward a hands-on career in a growing industry.

Total auto technician employment is expected to be 815,000 by 2033.⁴⁷ Attending a trade school like Universal Technical Institute (UTI) is a great way to gain the education you need for an entry-level position in the industry.¹

The Automotive Technology program offered at UTI can help give you the hands-on education and training employers are looking for.¹⁸ Courses cover a range of topics, like the various electrical systems and parts in vehicles, including alternators.

Want to find out more? Request more information.

UTI Campuses That Offer Automotive Technician Training

• Avondale, Arizona
• Long Beach, California
• Rancho Cucamonga, California
• Sacramento, California
• Miramar, Florida
• Orlando, Florida
• Lisle, Illinois
• Bloomfield, New Jersey
• Mooresville, North Carolina
• Exton, Pennsylvania
• Austin, Texas
• Dallas/Fort Worth, Texas
• Houston, Texas