6 Symptoms of a bad alternator


The alternator is an important component in the electrical system of your car. It restores the power that your car battery has lost while it is supplying the entertainment, climate, engine management and many other systems with the juice that they require in order to run properly by recycling the power it uses while you are driving. The alternator can create a cumulative effect of numerous electrical problems that can eventually cause your vehicle to breakdown when it begins to fail. The question therefore is how you will know when your alternator is failing. Well, the following are the symptoms of alternator going bad that you should watch out for in order to prevent your alternator from failing.

1. Flickering or dim headlights

The alternator forms part of your vehicle’s electrical system. Its key role is the provision of power to enable the ignition, starter, and all of your car’s electronic accessories to operate. You might start noticing that your dashboard lights and/or headlights are starting to dim if it begins to die. As soon as the headlights or dash light dim, this is a clear indication that your alternator might start to malfunction. Other electronic accessories like power seats and/or power windows may start to operate more slowly as compared to the way they usually do when your alternator starts to wane.

2. Visual Cues

If the electrical system of your vehicle is experiencing problems, the alternator might not be experiencing any problems because one of the belts that is connected to it could be the problem. You should do a visual inspection of your vehicle’s engine compartment in order to determine if one of the belts is too tight or too loose. You should also be able to spot if a belt is worn or cracked.

3. The indicator or warning light

Most modern cars are equipped with a dashboard indicator or warning light that helps in alerting you when the alternator is failing. Although some of the warning lights may say GEN (for generator) or ALT (for alternator), the light will usually be shaped like a battery. The light may only trigger when you are utilizing multiple electrical components. This generally depends on the amount of electricity your vehicle is utilizing and how much life the alternator of your vehicle has left.

4. Odd or strange sounds and noises

Many different parts produce electrical current by spinning inside the alternator of your vehicle. One of these parts could cause a whining or grinding noise if it breaks or is worn. Worn out bearings that are inside the alternator usually cause this kind of noise. A noise or sound will be produced if the bushings where your vehicle’s alternator is mounted on have failed.

5. Dead or weak battery

A car battery does not last forever because it has a finite life. An alternator can only recharge your car battery to the point where it gives it a decent amount of life that enables it to accept a charge. An alternator cannot bring your car battery back to life if the battery is dead or weak. You should restart the vehicle by charging the battery in order to determine if the issue is the battery or alternator. Your car will continue to run if the battery is dead or weak. However, the lights will again start to become dim after a while and this is an indication that the charging system has a problem. The problem is most likely with the alternator if your vehicle is unable to start even after its battery is fully charged.

6. Weird smells

An alternator works together with a unique system of belts. If one of the belts does not turn freely, the belt heats up because of the excess friction and in effect, this leads to the production of a burning rubber smell. If you happen to sense a smell that is similar to the one that an electrical fire produces, this could be an indication that the belt is causing very poor alternator output by slipping on your vehicle’s alternator pulley. You can prevent this by tightening the belt. If you cannot fix the alternator output and strange smell by tightening your belt, it is highly recommended for you to hire a professional to evaluate your car in order to detect symptoms of alternator going bad.


  1. I have put quite a bit of miles on my older car and the headlights haven’t been the brightest for a while. They have been flickering lately, so I hope it isn’t anything serious with the alternator. I will have to get it checked out.

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