In an automobile, the alternator is responsible for recharging the battery and supplying power for the car's electrical system. When an alternator is bad or failing, you may experience a variety of issues with your vehicle. Some of the top signs of an alternator that needs to be replaced include:
Since the headlights on your vehicle are part of the electrical system, they rely on the alternator to give them the power needed to keep them illuminated. As an alternator begins to fail, it will not be able to transmit power to the electrical components of a vehicle efficiently. This can result in the headlights being a lot dimmer than they usually are. It is also possible that interior lights inside the car may also dim. If you notice that your headlights or any other lights in your car are abnormally dim, contact a mechanic to inspect your vehicle.
When a car won't start, many people assume that it is due to a dead battery. But if your battery dies despite being relatively new, the real problem may be that the alternator is bad and is no longer charging the battery properly while the car is running. When replacing a dead car battery, it is also a good idea to have the alternator tested. The last thing you want is to purchase a new battery only to have it die again due to a failing alternator.
Drivers sometimes mention that they noticed an odd growling or whining sound in the days and weeks before an alternator fails and needs to be replaced. These strange sounds can occur if the alternator is no longer engaged with the accessory belt, serpentine belt, or the crankshaft pulley. Never ignore strange sounds coming from your vehicle—taking your car to a mechanic can help ensure that repairs are made and you don't end up being stranded on the side of the road in the near future.
The alternator transmits electricity, and when it is no longer working right there can be a burning smell before it fails completely. If a pulley is out of alignment and can turn like it is supposed to, it can create friction on the belt, which will create a smell of burning rubber. If an alternator overheats or is pushing through too much power, wires can get hot and start to smoke, which can create a smell similar to an electrical fire.
As the son and grandson of mechanics, I spent much of my child hood under the hood of many cars. I have listened and learned about so many different problems and how to repair them effectively. I created this blog to cover as many car problems as possible without overwhelming readers. You will find tips for troubleshooting, advice for when to take it to a professional and suggestions for when to stop driving the car or truck immediately to prevent further and more costly damage. We hope that you find all of this information helpful and useful, allowing you to have a great running car.