5 Signs Your Car Might Need an Alternator Repair

Alternators are one of the most under-appreciated components of the modern automobile, providing the essential function of keeping the battery charged so the car will start and all accessories function correctly. Without a properly working alternator, you will have frequent dead batteries and issues with the air conditioner, radio, or other accessories. Alternator repairs are a fairly common issue, and present some obvious signs for diagnosis.

First, it's important to have a basic understanding of how a car alternator works. An alternator is, essentially, a small electromagnetic generator that uses the rotational energy of the driveshaft to turn a piston inside a coil of copper wires. This turns the car's mechanical energy into electrical voltage, which is then sent into the battery where it can be stored and used to start the vehicle and power any systems that run on electricity.

Some people choose to upgrade their alternator due to increased power demands from modifying their vehicle, or sometimes they just wear out or malfunction due to normal wear and tear. Let’s look at the top five signs that you will need a new alternator or an alternator repair for your vehicle.

5 Signs of a Faulty Alternator

 1 Issues with the car’s lighting:

One of the primary signs that signifies a faulty alternator is issues with the headlights, such as noticing that they are too dim or that the brightness level fluctuates. They might also be flickering or behaving erratically, and you may notice that the interior lighting is also not acting like it should. If you notice any lighting issues with your vehicle, have the alternator checked out right away.

 2 Dead battery even after jump-starting the car:

If you experience an occasional, very rare dead battery, it’s usually nothing to worry about. Sometimes, they have reached the end of their lifespan and need to be replaced, or you may have left the lights on overnight and drained it. However, if you jump-start your car and get it running, then experience another dead battery shortly after, it is a strong indicator that you have a faulty alternator.

What causes this is the alternator failing to recharge the battery while you are driving. Usually, the energy that is depleted is replaced with energy generated from the alternator, but if it isn’t working properly this won’t happen and the battery will continue to end up completely drained.

 3 Frequent stalling and trouble starting the car:

Because the alternator is mainly concerned with the vehicle’s power supply, many of the ways to diagnose it rely on issues with the power. Similar to dead battery issues are problems you may experience with the vehicle stalling or not starting.

If the vehicle is stalling out while you are driving, it might mean that the spark plugs aren’t being supplied with enough power from the alternator. Also, if you notice the battery light glowing on your dashboard, it can indicate that the alternator is not working properly and the car should be examined.

 4 Bad smell like burning rubber:

Two alternator parts generally wear out the quickest and could be causing this issue: the alternator’s drive belt and the wires that supply power to the battery. Because it is running any time your car is near hot components of the engine, the alternator belt wears out just like any other drive belt does after enough usage. Likewise, the wires can overload or just wear out from general usage and start to burn or fray, which will give off a noticeable burning rubber/wire smell.

 5 Strange sounds like a high-pitched whine:

One of the most common sounds associated with a faulty alternator is a shrill, annoying, high-pitched whining sound that gets louder or goes up in pitch the more you accelerate. Along with this, watch out for grinding, squeaking, knocking, or really any other unusual sounds coming from your car, as they can indicate a serious issue with the alternator.

Checking the Voltage

You may be wondering if there’s a more foolproof way to diagnose a faulty alternator, as some of these conditions could be caused by multiple different issues. Indeed there is, and it only takes a simple tool called a multimeter or voltmeter.

To test the alternator, simply use the multimeter or voltmeter to touch the terminals when the car is off, checking for a reading of around 12-13 volts. Check it again when the car is running, and look for a reading of around 13-14. If your reading is substantially different than that, it is an even better indicator than the above signs that you have an alternator issue, and you should look into upgrading, replacing, or repairing it.

If you are having any of these issues, contact an alternator specialist or repair shop today and make sure to mitigate the situation as quickly as possible. Waiting on or delaying this repair can cost even more in the future and lead to worse issues with your vehicle.