It's normal to think that the battery powers the electronics in your car. However, this job isn't carried out by the battery but by the alternator—another critical part of your car's electrical system. Because of this vital role your alternator plays, any faults that develop could have some problematic consequences. Keep reading to find out more about the alternator.

What Car Alternators Do

The alternator is your car's electrical generator that powers all the electrical components, such as headlights, power windows, and air conditioning, while the vehicle is running. It's also responsible for recharging the battery, which is used to start the car when the engine is off.

Alternator Components

The alternator is made up of a number of components that work to allow it to generate electricity.

Pulley

The pulley is found on the exterior of the alternator and turns via a drive or serpentine belt connected to the engine crankshaft, which provides the alternator with mechanical energy.

Rotor

This is a cylinder with magnetic poles and becomes an electromagnet as it spins.

Stator

The stator houses the rotor and contains copper wire windings. An alternating current is generated in the wire windings as the rotor spins.

Voltage Regulator

This regulates the electrical input from the rotor to maintain the desired output from the alternator.

Rectifier

The rectifier converts the alternating current to direct current, which the car battery works with.

Symptoms of Failing Alternators

Warning Light Turns On

The battery warning light turning on could mean that there is an issue with the battery, but it actually indicates that there is a fault with the electrical system at large. This might be due to a faulty alternator that has a drop in voltage capacity or exceeds the voltage limit.

Dim or Overly Bright Headlights

A faulty alternator might provide inconsistent voltage, resulting in over or underperforming equipment, such as dim or overly bright headlights.

Electrical System Failures

The alternator might be unable to provide enough power to the electrical system, causing parts to either run slowly or not at all.

Growling or Whining Noises

Growling or whining noises might be made by a misaligned alternator pulley or worn-out rotor shaft bearings. These should be rectified as soon as possible so that the alternator can function properly and prevent further damage.

Battery Problems

Because the alternator charges the battery, a faulty one might not be able to charge the battery correctly. In addition, a faulty alternator could actually drain the car battery. As a result, you may have trouble crank-starting the engine or begin to experience a stalling engine.

How to Choose the Right Alternator

Aftermarket or OEM

Original Equipment Manufacturer (OEM) alternators are typically made by authorized manufacturers, whereas aftermarket alternators are made by third-party manufacturers.

We recommend investing in an OEM alternator to return your vehicle to its original level of performance. Because of the more stringent levels of manufacturing, you'll likely get more use out of an OEM replacement. Not to mention, aftermarket units may void your vehicle's warranty.

Vehicle Compatibility

Ensure the alternator you're getting is compatible with your vehicle. Check with your owner's manual to make sure it has the same voltage rating, is the correct physical size, and has all the same mounting points.

Output Ratings and Matching Vehicle's Electrical Demands

Make sure the alternator you're purchasing is of the right voltage rating so that it can keep your vehicle's battery charged and meet the electrical demands of your vehicle's electronics. If you have installed any high-performance aftermarket parts onto your car, you might want to check that the alternator you're getting is able to support them.

Installation and Considerations

While it is possible to replace your vehicle's alternator yourself, we recommend seeking a professional's help due to its complexity and the specificity of the tools required. Otherwise, if you're feeling up to the task, you can follow the following steps.

Tools Required:

1. Hand tools like ratchet sockets and wrenches
2. Belt tensioner tool
3. Safety gear like gloves
4. Battery tender or memory saver
5. Jack, jack stands, and wheel chocks

Once you have the necessary tools on hand, you can go about installing your vehicle's alternator.

1. First, disconnect the negative battery cable to avoid a short circuit. Refer to your vehicle's owner's manual to determine if you have to use a battery maintainer.
2. Locate the alternator, which should be mounted to the engine on either the front or the side. You might only be able to access the alternator from under the vehicle, in which case you will have to jack the car up.
3. Check all the other parts in the charging system, such as the drive belt, drive belt tensioner, electrical plug pigtail connector, and battery terminal B+ voltage wire, for any damage and malfunctions.
4. Remove the old alternator by unbolting it from the engine and mounting brackets.
5. Check that the alternator you are about to install is compatible with your vehicle.
6. Install the new alternator by aligning the mounting points and tightening the bolts and nuts. Place the drive belt in position and rotate the belt tensioner to install the drive belt, then reinstall all the electrical connections.
7. Reconnect the battery cable ends to the battery. You might want to apply battery post grease to the top and sides of battery cable ends and battery posts to prevent acid buildup and corrosion.
8. Test the alternator output with a multimeter. With the car running, you should see 13.25 to 15 volts with a fully charged battery.

If, for any reason, the alternator isn't charging post-installation, make sure all the connections are secure and free from corrosion, that the drive belt has the right tension, and that no fuses are blown.

Where to Buy Quality New & Used Alternators

You'll find new and well-maintained used alternators for your vehicle at great prices here at BE FORWARD Auto Parts.