6 Symptoms of a Bad Alternator

The alternator delivers power to all your car’s electronics while driving. Here are some signs to look out for if your alternator is going bad.

Most newer cars come with a lot more electric components but to power up all these components without any problems, you need a power source which happens to be the alternator.

Your alternator not only charges the car’s battery but powers the entire electrical system of the car including the lights, ignition, stereo, and so much more.

The alternator is connected to the battery to ensure your battery does not run out while the car is running.

That said, you might not know when your battery should be replaced or how much it will cost but you need to find out. Here are some significant signs you should watch out for.

Replace Alternator

The standard symptom your alternator is going bad is the warning light on your dashboard. Other symptoms include the lights on your car are flickering or you have issues starting your car. If you hear sounds coming from the engine, it’s almost definitely coming from a failing alternator.

While this is a simple list of issues caused by the alternator, it’s time to take a closer look into the symptoms caused by your alternator.

The Battery Warning Light

If you have checked all the warning lights on your dashboard while the ignition is on but your car’s engine is not running, you should notice a warning light with a car battery icon.

There are 2 conditions you should watch out for:

The ignition is on and the battery power is over 13 volts. Normally, your car battery has 12 volts and when the alternator is charging, it should read approximately 14.2 volts in your system.

Should the voltage in the system drop below 13 volts while the ignition is on, the battery light will light up on the dashboard stating your alternator is not charging correctly.

The Headlights Are Dim Or Flickering

Dim Headlights

Your headlights are one of the most demanding power sources requiring a lot of electricity. The more power your headlights receive, the brighter your headlights will be.

If the alternator is failing, the voltage to your headlights will drop and they will become dimmer. If your headlights seem to be even dimmer than previously, the chances are the issue is with the alternator.

If you notice your headlights flickering, that’s coming from an unstable voltage coming from the alternator.

Newer cars have LED headlights so you will not experience dimming lights from a failing alternator. The downside is the lights could turn off completely before you even realise it!

Car Starting Problems

Car Starting Problem

Every time you drive your car, the alternator should completely recharge the battery. The next time you are parked and then want to drive, it should be fully powered.

However, if the alternator is going out, it might not charge every time you drive. At some point, your car will drain more power than it is charging. Eventually, your car will not turn over.

If you think your car feels tired every time you start it, it could be an issue with your alternator.

Noises Coming From The Engine Bay

The alternator consists of bearings and other spinning electronic parts. If your alternator has been damaged, you could hear squealing or banging sounds coming from it.

The most prevent problem is a bad bearing inside the generator which will cause a scratching sound. In general, alternators are easy to see from the engine bay so it’s pretty easy to open and listen for if you can locate where the alternator’s noise is coming from.

Unfortunately, some cars have alternators that are located far down in the engine bay and can be very difficult to listen to for noises. In cases like this, you should contact a professional mechanic to help you out.

The Battery Drains

Flat Car Battery

If you are charging your car’s battery regularly but the battery is continually draining even if it’s in good condition, more than likely the culprit is your alternator.

There are a lot of reasons why the alternator is not charging properly. We have several articles you should read covering issues why the alternator is not charging properly.

Other Electronic Failures

If an electronic component is not getting the right voltage, there could be several reasons why. As mentioned earlier, newer cars have many electronic parts that require power.

Obviously, low voltage caused by a bad alternator can cause many strange issues both inside and outside your car. If you think something strange is going on with your car, it’s a really good idea to check the alternator or get someone to help you out.

Alternator Locations

The alternator is normally located at the front of the engine near the serpentine belt. It’s usually at a high point of the engine but it can be located farther down.

The serpentine belt powers the alternator and this belt is powered by the crankshaft pulley. This pulley is always located at the front of the engine.

The alternator is a critical part of the operation of your car. Have it checked out once in a while to make sure it’s running properly.

If you believe you may have a problem with your alternator you can have it checked in and around Manchester city centre and North Manchester, Oldham, Bury, Bolton, Rochdale, Stalybridge etc. by Servicing Master. You can get a quick repair or service quote by using our simple car service quote form. We also offer a collection and drop off service. A convenient, friendly and affordable service, try Servicing Master once and you’ll never go back. Give us a call now on 0161 302 0201. Or simply book your car service now.

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