Even if you’re not a car expert, you can try a few simple things to check if your alternator is bad.
Start by checking the battery
Your car’s battery is what turns the alternator into action. If the battery is not working properly, this could explain why your alternator is acting funky. You can use a multimeter or voltmeter to check the voltage of your battery. Just attach the red cable to the positive battery terminal and the black cable to the negative terminal. A voltage reading of 12.2 is enough to power the alternator.
Test the alternator gauge
If your car has an amp gauge, then you can monitor the alternator with it. Turn on your car and rev the engine at 2,000 rpms. Switch on other functions like the lights and AC or heat to see if the alternator gauge’s reading goes down. This indicates that the alternator is working properly.
Listen for noises from the alternator
Turn on your car and listen for any sounds coming from the hood of your car. Run the engine and turn on the lights and wipers – anything that will use more electrical power. If more noises come from the hood when you turn these functions on, it could be that there’s a problem with the alternator.
Is there a warning light on your vehicle?
Sometimes, if the alternator is putting out power below or above the car’s pre-set limit, then a light might appear on the dashboard. This usually looks like a red battery symbol.
If you suspect that your alternator is experiencing issues, you can go to an auto parts store and have the staff check on it. Most places do it for free and can offer you advice. Just be sure to go to a reputable shop so that you avoid being swindled.