The alternator is probably the most mysterious of automotive parts. What you may not have a real understanding of exactly what purpose it serves, and the thought of it malfunctioning and having to replace it is enough to make you want to clutch your wallet or purse. So, what exactly is this part and how can you tell it’s problematic before you even take it into the shop?
What is It?
If you’ve ever wondered how your car seems to have an endless supply of electricity, you can thank your “secret” power source for that. Although your car’s battery plays a major role in powering the lights, stereo, infotainment and other accessories, it would quickly lose its power if it were their only power source. That’s where the alternator comes in. It charges your battery while the car is running by turning the mechanical energy of the engine’s rotating crank shaft into electricity. That electrical charge boosts the battery and sustains the other systems while the car’s turned on.
Clearly, then, issues with this part will impact your car’s performance. Here are five ways to tell if it’s failing.
Dim Lights
The most obvious sign of trouble is if you notice dimming or flickering headlights. If your headlights or your dash and dome lights aren’t shining as bright as they’re capable, it’s likely because your battery is left to power everything on its own and isn’t getting any backup boost.
Dead Battery
In addition, if your battery’s working by itself, it won’t be long before it’s totally drained. While it’s possible for batteries to fail on their own if you leave your lights on for an extended period or if it’s just plain old, a new battery or one that’s in otherwise good shape that dies out quickly may be a sign of something troubles with your alternator.
Engine Stalling
Your engine cutting off while driving or not starting at all may also be a sign of trouble. The spark plugs and fuel injection need a good amount of electrical power to function properly.
Check Engine Light
Depending on the make or model of your car, the “Check Engine”, “ALT” or battery indicator may come on. If your battery’s new or you switch it out and the battery indicator stays on, then it may be time to check elsewhere.
Strange Sounds
You should be concerned anytime your car is making strange sounds- there are several potential causes behind those sounds. Specific to this issue, if your serpentine belt is stretched and not spinning the alternator pulley correctly, this can lead to a lack of charge which results in a squealing noise. It’s also possible that the alternator’s internal bearings are worn out, which can also lead to a growl or grinding noise.
Get It Fixed
If your indicator light is on, then it’s easy for your local shop to determine the root cause using a code reader. If you’re experiencing any of the symptoms above without a warning light, then other tests can be run on your battery and other systems before officially diagnosing the alternator as the root of your problems.