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Signs of a Bad Alternator & A Simple Way to Test it

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Most people know that an alternator helps recharge a vehicle’s battery. The alternator does take care of the battery, but it is actually a key component of the car’s life-line or electrical system. For one, it is responsible for making sure that the energy created in the crankshaft of your car is converted into an electrical current that can be used somewhere else within the car, including the battery. Still, just like any other part in your car, this component can fail. You should learn the signs and what to do about your suspicions.

Signs of a Bad AlternatorThere are a few signs to look for when the alternator is failing, and some are quite easy to detect, like the indicator light blinking on your dashboard. The little light should be labeled Alt or GEN, but some cars do not have the indicator light for this particular component. This makes it a little harder to detect an issue, but it is not impossible.

Look At Your Lights

One of the most telling signs that the alternator is failing shows up on your headlights. The alternator is responsible for providing your headlights with enough power to light up your nights, but a failing alternator will struggle with this task. It will appear as if your headlights are dim, or they may flicker from time to time.

Power Struggles

Another obvious sign of trouble is if you begin to have power issues. This could be as strange as your power windows going up or down at a very slow pace, or you may see the dashboard lights get a little dim. The car radio may actually turn off and on should the alternator be on its way out.

Engine is Just Not Kicking

You need a few things to start your car, and one of those things is power, which your alternator is partly responsible for. It makes sense that your car might have trouble starting if it starts at all. At this point, your alternator may need to be replaced immediately by your mechanic.

Battery Drains

You should be weary of your alternator if you notice that your car battery drains a little too quickly, and you are forced to replace it. Another sign is if you must jump start the battery, even though you just replaced it.

These are just some signs to look out for, which usually means that you have an alternator issue.

What You Can Do About a Bad Alternator

The first thing you should do is make sure the alternator is really the problem. Thankfully, it is not too hard to test your alternator as long as you have a voltmeter, and you are sure that your car battery is in good condition.

Connect the voltmeter leads to the battery terminals when the car is off. The reading should be between 12.5 to 12.8; this indicates that the battery is good. Leave the voltmeter connected, and turn on the car to get a new reading. The new reading should increase to 13.8 all the way up to 15.3, which indicates that your alternator is still in good condition.

Of course, if the numbers do not rise, then it is likely that your alternator is faulty. There are a few steps to take here, like finding a replacement at Gresham Auto Wrecking, which is probably the cheapest route to fix the problem on your own.