Most people assume that their battery is dead when their car will not start. However, your battery relies on your alternator to keep it charged and help it hold its power. Before you go and purchase a new battery, you need to check the output on your alternator to see if that is the real issue for your vehicle not starting.
How Your Alternator Helps Your Battery
The battery and the alternator work together to get your car started every time you turn the key in the ignition. When your car is running, the alternator is continually providing voltage to your car battery. This allows your car battery to recharge as you drive.
What You Need To Purchase
If you do not have one, you will need to purchase a digital voltmeter. Digital voltmeters can be used to diagnose a variety of different car problems. You can purchase one at your local automotive supply store. All you need to test your alternator is a voltmeter.
Getting Your Car Ready
You will need someone to help you test out your alternator. You need to park your vehicle somewhere safe where you feel comfortable working under the hood of your car. Set the voltmeter to the "DC" scale, and set it to at least 15 volts. This will allow you to easily read how many volts your alternator is putting out.
Open the hood of your vehicle and find the battery. Once you find the battery, remove any plastic guards that are covering the terminals on the batteries. The red positive clip from the voltmeter should be attached to the positive terminal of your car battery. The black negative clip from the voltmeter should be attached to the negative terminal of your battery.
Have a friend sit in the car and turn the ignition on. Your vehicle has to be running in order for you to read your alternator's output. Make sure your vehicle is in park.
Once you have attached the positive and negative terminals from the voltmeter to your car's battery, have your friend press slightly on the gas pedal. Have them look at the RPM gauge. They should aim to hit around 2,000 to 2,5000 RPMs from this slight pedal pressure. This is enough RPMs for you to properly test out your alternator.
While your friend is giving your car a little gas and revving up the engine, you should be checking the digital display on your voltmeter. If the alternator is working correctly, you should see a reading somewhere between 13 to 14.5 volts.
A reading within this range indicates that everything is fine with your alternator and your battery may be preventing your car from starting. A reading above or below this range, however, is a very strong indicator that something is wrong with your alternator, not your battery.
Do not assume that your car battery needs replaced just because your vehicle will not start. With a voltmeter, you can easily check and see if your alternator is working properly. If the alternator is working properly, then a new battery is in order. However, if the voltmeter gave you a reading that was not within the normal range, you should have a mechanic further inspect your alternator.
To learn more, contact a company like AERS Auto Electric & Refrigeration Ltd with any questions you have.