So after brewing a nice cup of coffee in the morning, you grab your bag and hop into your car that’s been sitting in the garage overnight. As you turn the key in the ignition and your engine roars to life, you suddenly hear a loud whirring sound that is pretty unsettling.

That’s weird – the car was running just fine as you drove home the night prior, so why is this happening? It may be your vehicle’s alternator.

The Purpose of the Alternator

You see, your alternator is located on the engine, and it provides power to the battery, the car’s electrical systems, and the various computers. Basically, it’s the hardest working part of a vehicle – the battery starts the car, and the alternator keeps it running.

An alternator typically lasts around 7-8 years or 100,000-150,000 miles. Of course, there are several factors that affect the lifespan of an alternator such as the quality of the part itself, the conditions that the vehicle is driven in, and the kind of electronics found within the vehicle. This may shorten the lifespan of the component.

Other reasons your alternator may fail include a jump start gone wrong, incorrect installation of an aftermarket electronic that overloads the battery, and more. This is why in some cases, the battery may be dying because your alternator is going bad, so don’t rush out to buy a new battery without fully understanding the position you’re in.

The Location of the Noise

You may first assume your engine is failing since it’s so easy to point to that as the perpetrator. A lot of the time, you can tell whether this is the case if the Check Engine light appears on your car’s dashboard. As we talked about, your battery may fail due to it being overloaded, so the battery light could come on.  Check your car owner’s manual to understand what we are referring to.

At this point, you should take a moment to listen to where the sound is coming from. If the noise is focused more towards the center of your car than the front of it (or the back of your car depending on where the engine is located), that may indicate an issue with the alternator. Make sure you visit a reputable auto repair shop that will be able to diagnose what the situation really is.

The Cost to Replace an Alternator

Now, here is where we come to the big question – how much are you going to end up paying to have your alternator replaced? Other than the fact that a lot of it comes down to where you have this service performed and the kind of vehicle you operate, the average price to replace an alternator with a remanufactured one can range from anywhere between $300 to $500 (including parts and labor).

While this can often be a difficult pill to swallow on the cost alone, many alternators come with at least a one-year warranty so you don’t have to worry about driving off the lot with a less-than-satisfactory repla\cement. Be sure to check with your mechanic to find out how long the warranty lasts and what type of scenarios it covers.