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How To Test Alternator By Disconnecting Battery?

An alternator is an electrical powerhouse or brain of the car which keeps the devices in the car in a working state and also charges the battery simultaneously for using it afterward. The alternator is a very important part of the car just like the brain which is the most prominent part of a human body, without which one cannot imagine their lives. Likewise, our cars can also not live or provide services to us without good Alternator.

So here in this article, we will tell you a way by which you can check whether your car’s Alternator is in a proper working state or not. Below we have discussed the testing of the alternator by disconnecting the battery.

How to test an alternator by disconnecting the battery

How To Test an Alternator Steps To Follow (Via Disconnecting Battery)

Last update on 2021-09-12 / Affiliate links / Images from Amazon Product Advertising API

First, we will find out some signals. These signals tell us that the alternator is good or not. Understanding these signals is easy and reliable as these give a direct check on the components working on Alternator. So if there is some issue with these components it’s a clear indication that there is some problem with Alternator.

  1. If you see a warning indicator light go “ON” there are sure chances of malfunctioning of the alternator. The indicator light has two labels on it, either “GEN” or “ALT”.
  2. The Headlight of your car may flicker again and again or in some cases, the Headlight may get dim in the “ON” state. This happens because after starting the car by battery its alternators duty to give power for keeping the light ON properly and if it’s not in good condition the headlight will surely face problems in glowing nicely.
  3. If your battery is going dead regularly and needs charging in just two or three weeks then this thing also indicates that there might be some issue with your Alternator because Alternators quickly get affected by the improper charging system of the car.
  4. If devices like Air conditioner, Radio, power window, Dashboard Lights do not function properly then your Alternator is not working well. An alternator is an electrical powerhouse that takes care of the working of these devices.
  5. Your car will start stalling if your car’s Alternator is not well as Alternator provides electricity to the stator for starting the car.
  6. If any of 2 or 3 problems among the above signals are arriving in your car do not wait more and go to the mechanic for checking the Alternator.

How to Test Your Car’s Indicator

Now, here we will tell you the way to test your car’s indicator by yourself, by disconnecting the battery of the car.

  • Take the car to a safe and open place and keep it away from an under knowledge being before starting the process. Ex: children, pets, or old age should be told to stay far away from the car before disconnecting the battery.

*Remark: It is important to keep these people away while performing the process since this test is dangerous.

  • Open the hood of your car. Check if it’s properly supported by the hook rod or not.
  • Start the engine. If your car is already having difficulties in starting the car it may take time to start it. If it starts, keep the engine running.
  • Go back to the battery. Check if there is some dirt or corrosion around the battery’s terminal. Remove it if present.
  • After this disconnect the battery and simultaneously keep the car in running state.
  • See if the car is running or not.

If your car is still running then it’s a great thing your car’s Alternator is completely OK, there is no problem with your Alternator. If it’s not working well then, your car would have stopped after disconnecting the battery.

Since, after starting the car it’s your car’s Alternators’ responsibility to give power to the car’s engine which is capable of running it in the present time. This is the reason we are saying that your Alternator is in bad condition.

Yes, if it’s not working then now you should go to a mechanic for the confirmation and also for its repair or replacement.

Also, check if your Alternator is good then make sure to check other components because of which your car was showing the above signals of malfunctioning.

Note:- Although, here we have talked about how to get to know whether our alternator is working well or not. But the thing to be kept in mind is this method of disconnecting the battery is not the correct, reliable, and safe way to test the Alternator.

Frequently Asked Questions

Q1.Why it’s not safe and trustworthy to test the Alternator by Disconnecting the battery?

An alternator can provide energy to the engine when you take out the battery while running the engine, but the factor we should look upon is that the battery acts as a buffer by maintaining the energy flow of electricity inside the electrical system. If the battery disconnects a whole load of providing the car’s engine and other electrical devices come on Alternator and it generates high voltage electricity of about 150 V (This value differs with rpm count of the engine). Due to this much high voltage electricity flows into the electrical components of the car it heats up and leads to damage of thousand dollars electrical devices. This may also lead to some bursting of the car’s components due to reaching excess power into them, more than their need.

Q2.What is the other option to test the alternator of your car?

The other way of testing the Alternator is by using a voltmeter. In this, we connect the voltmeter to the terminals to check the electricity flow by which we can predict how nicely the Alternator is working because it regulates the electricity in the car.

Q3.What are the precautions should we take while testing the Alternator by disconnecting the battery?

Although, this matter is itself not safe for testing the Alternator still if we take care of some small things while processing we can avoid accidents which can be very harmful to us.
1. Check whether the rod is properly supporting the hood or not.
2. Do not touch the terminals with naked hands.
3. Turning “Off” the engine after some time does not leave the car in this battery’s disconnected state.

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