The alternator is an electrical generator in your car with the purpose of charging your car battery. It's also the part of the vehicle in charge of the lights and other electrical systems in your car. Having a fully functioning alternator is of major importance for you to be able to operate your vehicle in a safe and effective way. However, it's not always apparent that it is the alternator that is malfunctioning if your car starts to act strange. There are some signs that can tell you if your alternator is malfunctioning and needs alternator repair.
Under and overcharging
An alternator in poor condition can cause many different problems in your car. If it stops working, your car will also stop as the battery runs out of power, and it won't be able to start afterwards either as the battery is empty. An alternator that is overcharging your battery is not good either, as it can boil your battery dry and cause it to fail. An easy sign to tell if you have an alternator that is overcharging your battery is that you will have to change batteries uncommonly often. A normal battery should be able to last 5–7 years, and if you have to switch batteries much more often than that, it can be the alternator's fault.
Signs of a malfunctioning alternator
If your alternator is failing, but not enough to cause the battery to die completely, you can be able to tell by checking if your lights are dimmer than usual. Turn on the lights when it's dark outside; it makes it easier to notice if they're less bright than usual. A malfunctioning alternator can also cause the battery light in your car to turn on and limit the amount of power in the battery. If you're having reoccurring troubles starting your car, this could be a sign.
Have it checked
Of course, these signs could all be indications for other malfunctions in your car as well. If you're experiencing any of these things, the easiest thing is to check your alternator with a voltmeter. Put the voltmeter across the battery, and if the voltage is higher or lower than 14.2, this could indicate an alternator malfunction. If so, you should take your car to a shop, so that they can check the alternator and the battery. Sometimes there can be other problems with the battery that are causing these errors in your vehicle. If it is the alternator that is misbehaving, it's just a matter of repairing or replacing the alternator to have your car operate as it should again.