How to test if alternator is bad

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Is it a Bad Alternator or a Bad Battery?

There’s this awful moment when you turn the keys in the ignition, or press the start-up button, but the car engine won’t start. It doesn’t mean that you’ve got a bad engine, but rather it could be that there isn’t enough power to start the car. If you run into this situation, it is usually any one of two that might be letting you down- the battery or the alternator.

But then, how do you identify the culprit without being an expert? After all, you need to know what’s causing the problem to help you make the right repairs.

Battery at Fault:

Whenever you are having any power problem with your vehicle, the battery is the first thing you should examine. Why? Because compared to the alternator, the life expectancy of the car battery is low (usually 3-5 years) and is bound to make you scratch your head more times than the alternator. And yes, we all know recent car models are equipped with inbuilt diagnostic systems, but it’s not a good idea to always rely on them to tell you what is actually wrong.

For starters, you might want to perform a jump-start to see if the vehicle will start up again.

A jump-start is a process of starting a motor vehicle by passing an electrical current from a charged battery to the discharged battery of the vehicle being started, by means of a booster cable connecting the two batteries. If you don’t have jumper cables, then hope you can ask a friendly stranger to help you that has cables. Or contact a company such as AAA.

If the jump-start gets the vehicle running again, then you have a bad car battery. And you need to find your way to get your battery replaced. Aloha Auto Repair will guide you to the accredited battery dealers in Allen, TX.

Another way to easily tell when you have a bad battery is if you see an illumination on the dashboard from the battery light while you’re on the wheels. This is one of the most peculiar signs. In this case, you don’t have to wait until the battery is completely dead before you do something about it.

It’s also important to note that a bad car battery will likely give a clicking sound when you try to start the car while a dead battery will not give any sound at all.

Don’t forget to inspect the battery for signs of a split wire or a corroded lead, as these are usually pointers to a bad battery.

Alternator at Fault:

If you discover the battery is working fine and yet the car still refuses to start, then your alternator must be the problem.

An illuminated dashboard light can indicate a problem with an automobile charging system. However, a very simple way to check if the alternator is working is to run the car and disconnect the positive terminal of the battery. If the vehicle stops running, then you probably have a bad alternator.

You can also examine your interior and dashboard lights. If you notice the lights emerge brightly but slowly begins to dim with time, then you have a bad alternator on your hands. This is because even though the battery starts the ignition and lights, it actually relies on the alternator to keep working when the car is running. So when the lights come on but don’t sustain the same level of brightness, then the battery is not properly being charged by the alternator.

Besides dim lights, a failing alternator can also show symptoms of strange sounds when you try to use the car stereo.

What Happens When the Repairs Get Postponed?

A bad alternator can easily lead to a bad battery. Here’s how; after the battery starts the vehicle, the alternator takes over in charging it while the vehicle is running.

So when the alternator is bad, the battery begins to compensate for the power the alternator should have generated, because the car battery is not designed to supply power for extended periods, it will eventually wear out causing the vehicle to stop working.

Always stay vigilant and look out for signs of a failing alternator or battery, so you don’t get caught unawares. You can visit a reliable car repair shop like Aloha Auto Repair for regular routine maintenance or replace a bad car part.

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