If you own a vehicle, you probably would have heard about the alternator. It is an integral part of the electrical system, and you would have a hard time starting your car without it. So, what exactly does an alternator do? Where is an alternator located? Today, we will answer all these questions and much more.
Apart from electric cars, almost all other vehicles on the road have alternators under their hoods. And with the number of electrical components in a vehicle increasing day by day, the need of having a properly functioning alternator has become more important than ever.
As with any other vehicle component, the alternator can fail over time as well. In that case, you’ll have to replace it with a new one, and knowing where the alternator is located will come in handy. We know that you are curious to learn more about the alternator, so let’s get started.
Your vehicle needs both mechanical and electrical power to function properly. Although the engine takes care of providing mechanical power, it needs some help when it comes to powering all the electronic components of a car like the radio, headlights, and the infotainment system.
You may ask “what about the car battery?” Well, you see, the battery can’t power all the electronic components on its own. The battery is essential to powering up the car, but when the engine is running, it is the alternator that takes care of powering most of the vehicle’s electronic components. Simply put, the alternator recharges the car battery by distributing electricity to it.
The roots of the alternator spread all the way back to 1832 when Hippolyte Pixxi introduced its concept to the world. Other leading scientific innovations that lead to the creation of the alternator include Antonio Pacinotti’s continuous current DC generator in the 1860s, the installation of AC generators in 1878, the creation of a commercial use 15 kHz generator by Nikola Tesla in 1891, and the discovery of electromagnetic induction by Michael Faraday and Joseph Henry in 1831.
The military was the first to use alternators in road vehicles. This happened during the days of World War II. Back then, the main use of alternators was to power radio equipment inside specialized vehicles.
Other special vehicles like radio taxis and ambulances started using alternators later down the line. Alternators didn’t make an appearance in standard road-going vehicles until the 1960s.
There are several key components inside the alternator. Some of them are,
- Voltage Regulator
Now, let’s take a look at each of these components. This will help you understand the inner workings of the alternator.
Where Is An Alternator Located, Components #1 – Housing
The main function of the alternator housing is to protect the internal components of the alternator. This is the most visible part, and it is typically made using lightweight materials like aluminum. The housing can be divided into two main parts, the front housing and the rear one.
When people ask “where is an alternator located?” the best way to answer is by pointing out the housing. Most modern vehicles have alternators towards the front of the engine bay, bolted to the side.
Where Is An Alternator Located, Components #2 – Rotor
The rotor acts as a spinning electromagnet that resides inside the alternator housing. Its assembly consists of the rotor coil, rotor shaft, cooling fans, slip rings, and north/south claw poles.
The rotor drives the belt system and builds a magnetic field using the current that flows from the batter to the rotor coil.
Where Is An Alternator Located, Components #3 – Rectifier
A car battery uses direct current (DC) in its charging process. However, the alternator produces alternating current, which has to be converted to direct current in order to be used by the battery. This process is done through the rectifier. The rectifier consists of 6 or more diodes, and it is connected to the stator.
Where Is An Alternator Located, Components #4 – Stator
If you have ever seen an alternator, you might have spotted an iron ring with wire coils wound around it. This is called the stator. On top of acting as the body of the alternator, the stator creates electrical current using the magnetic field.
Where Is An Alternator Located, Components #5 – Bearing
Allowing the rotor assembly to rotate freely is the main purpose of the bearings. Additionally, the bearings make the rotation process smoother as well. They are attached to either end of the rotor shaft and placed on the alternator housing.
Where Is An Alternator Located, Components #6 – Voltage Regulator
The energy produced by the alternator has to be regulated in order to be safely utilized for the electronic systems in the vehicle. The alternator’s voltage regulator is responsible for this. Furthermore, distributing the power produced by the battery is another responsibility of this component.
A malfunctioning voltage regulator results in the battery receiving too much or too little power, leading to major issues down the line. Overall, external voltage regulators used by older cars have largely been replaced by IC-type voltage regulators.
Where Is An Alternator Located, Components #7 – Pulley
The pulley interconnects the alternator’s rotor assembly with the engine. This is done with the use of a belt called the drive belt. However, some gearheads refer to this belt as the alternator belt as well as the serpentine belt.
The main function of the pulley is rotating the rotor assembly along with the engine. You can find three types of pulleys in modern vehicles. They are,
- Solid Pulleys
- One-way Clutch Pulleys (OWCs)
- Overrunning Alternator Decoupler Pulleys (OADs)
No matter what type of pulley your vehicle has, they all function in a similar manner to fulfill the same purpose.
With that, you now know the basics of the alternator as well as its main functions. Similarly, now you have a clear idea of why the alternator is such a crucial element of a car as well.
In the next section of this article, we will take a look at the different symptoms you can use to identify a faulty alternator before it causes too much damage to the crucial electronic components of your vehicle.
Bad Alternator Symptoms
As we have already established, your vehicle depends on the alternator for all its electronic functions. Over time, the alternator will wear out with use. Some symptoms of a worn-out or bad alternator are (which will help you in learning how to tell if your alternator is bad and how to know if your alternator is bad),
- Dim Or Flickering Lights
- Warning Light On The Dashboard
- Difficulty In Starting
- Slow Accessories
- Strange Sounds
- Weird Smells
- Dead Car Battery
Bad Alternator Symptoms #1 – Dim Or Flickering Lights
Dim or flickering lights are one of the most common symptoms of an alternator that is losing its will to live. The headlights are some of the highest power-consuming accessories on a vehicle, so it takes a lot of effort from the alternator to light them up to their correct brightness.
A fault in the alternator will cause the voltage to drop, dimming the headlights in the process. Similarly, a bad alternator can cause unstable voltages as well. In this case, you will notice flickering of the headlights, with the brightness level fluctuating. On most occasions, you’ll start to notice the flickering before the lights start to go dim.
Modern vehicles come with safety mechanisms programmed into the ECU to prevent the headlights from suddenly going out, which can result in an accident. These vehicles have a priority list when it comes to electrical accessories.
So, when it detects an alternator failure, it will turn off the radio and heated seats and send all possible power to the headlights to give you enough time to safely pull over to the side of the road.
Bad Alternator Symptoms #2 – Warning Light On The Dashboard
One of the easiest ways to identify a faulty alternator is by the warning light on the dashboard. Most cars have an alternator warning light in the shape of a battery. However, some cars may display it as “ALT” or “GEN” too. Some people may mistake this warning light to be an indication of a battery issue due to its design.
Usually, the power output of an alternator varies between 13 and 14.5 volts. The vehicle constantly monitors this voltage output, and when it goes below a certain limit, the warning light turns on. The alternator warning light may also flicker during the early stages of the issue.
Bad Alternator Symptoms #3 – Difficulty In Starting
As you drive your car around, the alternator is constantly recharging the battery. This ensures the battery always stays topped up when you park your car. So, if your vehicle’s alternator is working as intended, you should have no trouble starting up the next time.
However, a faulty alternator won’t charge the battery fully. With the charge of the battery dropping day by day, a point will come when the alternator draws power from the battery instead of recharging it. From that point onwards, you’ll have trouble starting your vehicle.
If you constantly hear a ticking sound instead of the roar of the engine once you turn the key in the ignition, it is a sign that your alternator might be in need of some TLC.
Bad Alternator Symptoms #4 – Slow Accessories
The electronic accessories being slow to respond is another tell-tale sign of a weak alternator. The power-operated windows may take longer to wind up, the electronic gauge cluster won’t work properly, and your seat warmers may feel low even when they are on full blast. All these happen due to the alternator failing to supply a sufficient amount of power to these electronics.
Bad Alternator Symptoms #5 – Strange Sounds
As we discussed earlier, the alternator houses a number of different moving parts inside it. If one of these components fails, it can damage the others too, resulting in loud bangs and squeaking noises.
If you hear any strange sounds coming from the engine bay, be sure to take a good look at the alternator. When it comes to visual inspections, knowing the answer to “where is an alternator located?” will surely come in handy.
If the alternator makes a distinct scratching noise coming from the alternator, it is almost a given that the bearings have gone bad. These bearings are a common area of failure, and you’ll probably have to replace the alternator with a new one to get rid of the scratching sound.
Bad Alternator Symptoms #6 – Weird Smells
Similar to the unusual sounds we discussed earlier, alternator failure can give off weird smells too. Excessive wear on the alternator components is the main reason for this problem. As you may already know, the drive belt of the alternator sits close to the engine, and the combination of heat, tension, and friction can wear it out quickly. This is the cause of the burning odor that you smell.
Additionally, foul odors arise when an alternator is overworked as well. When an alternator is under too much stress, the amount of electricity flowing through is often too much for the wires to handle. As a result, they give off a smell similar to burning wires.
Not only that, but resistance created by the damaged wire causes resistance against the electricity flow as well. The resulting heat will intensify the burning odor. If you sense a weird smell coming from the engine bay, taking the vehicle to a certified mechanic is your best bet.
Bad Alternator Symptoms #7 – Dead Car Battery
This next symptom ties into a point we discussed earlier. A faulty alternator won’t sufficiently charge the car battery, so it will deplete sooner than you expected. If this happens, you’ll have difficulty starting your vehicle, and will have to jumpstart your car constantly.
Speaking of jump starting, you can distinguish between a dead battery and a faulty alternator through this process. If the engine stays running after the jump start, the issue lies with the battery.
However, if the vehicle dies immediately after jumpstarting, it is time to replace your alternator.
Those are some of the symptoms that can help you identify whether your alternator has gone bad. In case it has, knowing about the repair costs of an alternator would be really beneficial for you. So, let’s take a look at alternator repairs and the costs associated with it (as well as how to fix an alternator), shall we?
Once you have determined that the alternator of your vehicle has indeed gone bad, on most occasions you will have to replace it with a new one. If you are handy with some tools and love to work on your car, you can perform an alternator replacement in the comfort of your home.
However, before getting started on the alternator replacement (and figuring out how to change alternator and how to replace alternator and changing the alternator), make sure that you have the necessary tools at your disposal. In order to perform the alternator replacement correctly, you’ll need the following equipment.
- Hand Tools (Ratchets, Sockets, Wrenches, etc.)
- Battery Tender
- Wheel Chocks
- Jack Stands
- Safety Equipment
However, the exact tools you may require can vary from one car to another. Once you have gathered all the equipment, it’s time to get started. The alternator replacement process consists of several key steps (if you’re not willing to pay up the alternator replacement labor cost). Now, let’s take a look at each of them.
Step 1: Disconnecting The Alternator From The Car
Before diving under the hood to replace the alternator, you should park your vehicle on a level and even surface with plenty of room to work on. Then, disconnect the battery by removing the cable attached to the negative terminal.
Depending on where the alternator is located on your car, you might have to jack it up in order to remove it. If that is the case, lift it up using the jack, and insert jack stands for additional safety. Additionally, make sure to engage the parking brake before jacking the vehicle up.
With that, you are all set to go ahead and start working on the alternator. First, disconnect the main power cable, which runs from the battery to the alternator. This cable will be easy to identify, as the only other cable connected to the alternator connects it to the wiring harness. Removing the cable can be done using a ratchet on some vehicles, and by using an open-ended wrench on others.
After removing the power cable, you should release the safety clips connecting the alternator with the wiring harness. Be careful not to break the clips when removing the alternator.
Step 2: Taking Out The Old Alternator
After disconnecting the main power cable and harness safety clips, the process of removing the old alternator can begin. Make sure you’re wary of how long does an alternator last. Take a look at the alternator mounting bracket to see if it has any bolts that can slide from side to side. If so, your vehicle comes with an auto tensioner.
To release the pressure of the auto tensioner, start off by sliding the belt off of the alternator pulley. Then, apply pressure in a clockwise motion to relieve the tension on the belt. On the other hand, if the car doesn’t have an auto tensioner, loosen the bolts on the alternator and take the alternator out of the engine compartment.
Before starting the new alternator installation process and replacing the alternator, compare it with the old one by keeping them side by side. Ensure that the wire connectors and mounting holes are in the same locations and that the two alternators are the same size. If they don’t, it’s better to exchange the new alternator for another one that fits your vehicle properly.
Step 3: New Alternator Installation
Now it’s time to insert the new alternator in place of the old one. Place the new alternator inside the engine bay, in the same orientation that the old one was in. Be careful not to trap any belts, wires, or other components as you do so (or, if you don’t want to do this yourself, consider checking out our guide on how long does it take to replace an alternator).
Then, slide the mounting bolts into their brackets and tighten them. Route the belt around the alternator pulley in the same way it did on the older one. If necessary, use a pry bar to apply tension to the alternator until the belt feels tight. To learn more, check out our guide on the alternator repair cost and how long do alternators last.
When fighting, ensure that the maximum play of the serpentine belt is less than an inch. Finally, connect the monitor harness, power cable, and battery to complete the alternator replacement. For more insight, check out our write-up on how long should an alternator last.
Where Is An Alternator Located: In Conclusion…
No matter if your car is brand new or 20 years old, it will have an alternator under its hood. As we discussed, it is an important component of the engine, and your vehicle won’t function as intended without it.
Knowing the answer to “where is an alternator located” will surely come in handy when the time comes to replace it with a new one. You can use the information we provided you here today to replace the alternator by yourself in the comfort of your home.
FAQs On Where Is An Alternator Located
How Much Is An Alternator
The price of replacement alternators varies depending on the make and model of your vehicle. Usually, the cost ranges between $130 to $250.
What Does An Alternator Do
The alternator is a crucial element in the electrical system of a vehicle. It keeps the battery topped up during running. The alternator converts chemical energy to electrical energy in order to achieve replenish the battery in this manner.
How To Tell If Alternator Is Bad
If the electronics of your car start acting up, the chances of your alternator being faulty are highly likely. Some common symptoms of a faulty alternator include dim or flickering lights, difficulty in starting the vehicle, unusual sounds coming from the engine bay, and the alternator warning light turning on.
How Long Do Alternators Last
Typically, alternators are designed to last between 80,000 – 150,000 miles. This means that you’ll have to replace the alternator once every seven years or so. However, make sure that you aren’t wearing out your alternator prematurely. An overtightened serpentine belt, jump-starting the car in the wrong way, being subjected to extreme temperatures and fluid leaks can all cause an alternator to wear out prematurely.
How Much To Replace Alternator
The total cost of an alternator replacement is about $400. Although, you can save some money by replacing the alternator yourself. All you need are some tools, a replacement alternator, and a handy guide like this article.