Signs of a Car Alternator Failing

Alternators are essential components for keeping your car running, as they recharge your battery as you drive. A bad alternator can sneak up on you and allow your battery to completely drain, rendering your car unusable. There are a few signs that should alert you to a failing alternator, so make sure you pay close attention and never ignore any of your car's warnings.

Dimming Lights

Dimming lights are one of the first signs of a failing alternator, and should prompt you to get it checked immediately. When this happens, you will notice the lights on your instrument panel dimming at random times while you're driving; the headlights will also flash on occasion. This happens because the battery is not producing enough electricity to power everything smoothly, leading to slight power failings that become manifest as the occasional dimming of lights. The more often the lights dim, the closer your alternator may be heading toward failure.

Noises

You may notice strange noises coming from under your hood while the engine's running. A multitude of problems could cause a clamor, it's true. But if you hear a rattling-type noise coming from your alternator while the car is idling, then chances are that the bearings inside the unit that help it spin and produce electricity have gone bad, meaning it will soon need to be replaced.

Car Failure

Not being able to start your car is the most obvious sign of a bad alternator. If you frequently need to jump-start your car, then it can be one of two things: a bad battery or bad alternator. A battery, over time, will lose its crank amps even with a good alternator, so it may need to be replaced, anyway. But if you need to jump-start your car even with a new battery, then chances are that the alternator isn't working to power your battery and it's draining every second the car's running.

References

• Auto Education: Electrical System
• EconoFix: Alternator Repair