What Is a Car Alternator? And Signs of a Bad Alternator

Your car alternator is an important piece of equipment that charges your car’s electric systems. These components are bound to wear over time which can lead to multiple car functionality issues and safety concerns. Here is a breakdown of everything you need to know about bad alternators:

What is the Role of an Alternator?

Your car needs an alternator to charge its electrical system. An alternator works in coordination with your car’s battery to generate power to run the car.

In most cases, alternators have a limited life span and it is a wise idea to inspect and change them as needed. A bad alternator does not only put your safety at risk but also results in a lot of unpredicted inconvenience for you, the main inconvenience being that it will greatly affect your battery’s life.

You can watch out for a range of signs that indicate if your alternator is going bad and whether you need to replace it immediately. Let’s get to know these signs, shall we?

 

What are the Signs of a Bad Alternator?

Bad Alternators can be identified by the following signs:

Dimming/Flickering Headlights

Have you noticed your car’s headlights flicker as you change the engine speed? One of the major signs of malfunctioning alternators is that they fail to maintain a consistent brightness in headlights as you adjust the speed of your engine. You may notice that when you speed up your engine, the headlights will get brighter and vice versa.

Another major indicator of malfunctioning alternators is dimming headlights. Due to the fluctuations in the charging power of the electric system of your car, your headlight system and dashboard lights tend to wear and tear. If you observe any of these indications in your car, you can confirm that your alternator is no longer capable of generating appropriate power.

Dead or Weak Battery

Alternators play an important role in recharging your car’s battery. Unfortunately, they will eventually lose their efficiency to recharge your car battery and your battery may grow weaker or die at some point. Since it is practically impossible to keep the alternator working perfectly forever, extra care is needed to replace the car alternator and ensure battery functions.

Experts suggest that you can follow some guidelines to check whether you have a malfunctioning alternator or a dead battery in your car.

  • Check the battery gauge placed on your dashboard without starting your car
  • A strong battery charge message on the indicator means that your alternator and battery are working smoothly
  • If your gauge continuously indicates a low charge, it means that your alternator has worn out and your battery is growing weaker.

Since the electric systems of your car need an energy source to continue their functions, the system will shift to drag energy directly from the battery when your alternator has malfunctioned. As a result, your battery will not only drain quicker but also charge slower, grow weaker and die faster than in normal circumstances.

Strange Sounds (Grinding/Whirring)

If you break down the parts of an alternator, you will get to see an arrangement of many moving parts that spin to perform the functions of an alternator. Sometimes, your alternator may develop issues in the interior makeup which may be due to the ineffective movements or breakdown of a moving part. In this case, you will hear strange sounds coming from your car such as grinding which indicates that the alternator has developed wear and tear in its bearing.

In other cases, you may hear a whirring/whining sound coming from your car whenever you set the voltage regulator in motion. Whirring sounds are usually heard when the voltage regulator sends excessive charging signals to the alternator.

Electric Failures:

Another bad alternator sign is the occurrence of a variety of electrical failures. You can observe electric failures in the form of slowed-down car window movements, poorly performing power locks, abnormally heated seats, and slowed windshield wipers.

Will your car start with a bad alternator? Problems in Starting your Car

Although weak or dead batteries are the major culprit behind the difficulties car owners face while starting their cars, bad alternators can also be a reason for problems in starting the car. It is imperative to keep in mind that once you rule out the possibility of battery issues, it is likely that your car’s alternator is in bad condition which is why it is hampering the car’s starting ability.

Cars that have malfunctioning indicators will fail to start in most cases. However, you might be able to start your car after making several attempts. Even if you succeed in starting your car with a bad alternator, there are chances that your car will stop midway.

Is It a Problem With The Battery or The Alternator?

battery with rusted anode and cathode

Since indicator and car battery are interlinked, there can be several misconceptions that may make their way into your mind when it comes to identifying the root cause of different car issues.

Weak/Dead Battery Signs

Here is a list of signs associated purely with battery issues:

  • Sluggish engine cranking or difficulty in starting the vehicle in cold weather
  • Failure to turn on the sound and interior lights once you start the engine

Weak/Dead Battery signs are also associated with other problems like corroded connections, bad electrical draw, poor battery charging due to visible corrosion on terminals, and damaged battery terminals.

Some causes of bad battery include the failing alternator of the car, excessive electric draw from fuses, sound systems, interior lights, car alarms, electric locks, etc.

In this situation, jumpstarting a car works in almost all cases. However, it is important to figure out whether your battery has grown weaker in due time or there are hidden issues that led to a bad battery,

A bad alternator can lead to low battery or dead battery.

Will a car run with a bad alternator?

Picture Source: https://toytechs.com/what-you-need-to-know-about-your-vehicle-electrical-system/

The main reason why cars with bad alternators fail to run is that bad alternators can weaken the car batteries during recharging. Bad alternators overheat the batteries by overcharging them which leads to a decrease in the expected lifetime of a car battery and reliability issues. Although a bad battery will not damage your alternators, the bad alternators will eventually damage your car battery.

Steps to Jumpstart your Car with Bad Alternator

Here is how you can jumpstart your vehicle in case of bad batteries:

  • Choose a car with a good battery and turn its engine off.
  • Attach the red cable on the opposite end of the jumper cables with the red terminal of a good battery.
  • Connect the negative terminal of the good car battery with the black (negative) cable of the jumpstart. Attach the free end of the black cable to a suitable place for grounding the engine
  • Start the engine of the good battery car and let it run for a solid 3-4 minutes.
  • Attempt to start the car with a malfunctioning alternator and allow more charging if needed
  • Once the car starts, remove the cables and put them away without touching them with each other
  • This trick will only run your car for a couple of minutes and you shall run to a mechanic to fix your bad alternator and resolve any other issues.

Related Questions

Can a bad alternator kill a new battery?

Bad alternators lead to charging fluctuations in new batteries and they can weaken the new battery over time due to overheating. The new battery will eventually die if you do not replace the bad alternator.

If you are more of a visual learned, here is a video that describes 5 common symptoms of a bad alternator in a car.