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If you’re facing trouble with your car battery constantly dying, it may be time to test your alternator. The alternator is responsible for charging the battery while the engine is running, so if it’s not working correctly, your battery will eventually lose power and die. But don’t worry, testing the alternator doesn’t have to involve a trip to the mechanic or expensive equipment. You can easily test the alternator with just a screwdriver. So here, we’ll guide you through 8 simple steps on how to test the alternator with a screwdriver like an expert.

How to Test the Alternator with a Screwdriver 

The alternator is a vital component of your car’s electrical system, as it is responsible for keeping the battery charged while you drive. If your alternator fails, your car will eventually stop running altogether. Fortunately, testing the alternator with a screwdriver is an easy and effective way to determine whether it needs to be replaced.

How to Test the Alternator with a Screwdriver 

Insert Key in Ignition

Inserting the key in the ignition is often the first step to starting a car. It can also be used as the first step to testing your car’s alternator with a screwdriver. This simple test can help you determine if your alternator is functioning properly or needs replacing.

To test your alternator, insert your key into the ignition and turn it to the “on” position. Make sure all other accessories are turned off and that your battery has a full charge. Take a screwdriver and touch its metal shaft to the back of the alternator while holding onto its handle. If you see a spark, this means that electricity is flowing through your alternator and that it is working correctly.

Safe a Car Hood

Make sure your car hood is securely fastened after inserting the key in the ignition. It’s crucial for your safety and the safety of others on the road. To secure your car hood, simply locate the release latch under the dashboard and pull it towards you until you hear a click. Then, lift the hood and use the rod provided to prop it open.

Open Car Hood

The alternator is responsible for charging the battery and keeping the electrical components of your vehicle running smoothly. To determine if your alternator is functioning properly, you can perform a simple test using just a screwdriver.

Before starting the test, make sure that your car hood is securely propped open to prevent it from falling on you during the process. Next, locate the alternator and carefully remove any covers or protective barriers that may be covering it. Then, use a screwdriver to touch both the positive (+) and negative (-) terminals of the alternator at once. 

If there is no spark when touching these terminals together, this indicates that there is an issue with either your battery or your alternator.

Check the Alternator

Ensure that your vehicle’s engine is turned off before attempting to check the alternator. Open up the hood and locate the alternator, it should be mounted on the front of the engine block towards one side. Now, take your screwdriver and touch its tip to various parts of the metal outer casing of the alternator. Be careful not to touch any moving parts such as belts or pulleys as you do this.

Turning the Key to Position On

To begin, turn the key to position On without starting the engine. Observe the dashboard warning lights; if they do not light up, it may indicate a problem with your battery or alternator. Take a screwdriver and place it on the back of the alternator near the pulley. Listen for any changes in sound as you bring it close to different parts of the alternator.

If you hear a clicking or buzzing noise when touching certain parts of the alternator with your screwdriver, this may be an indication that those specific components are faulty.

Get the Screwdriver Close To the Alternator 

Now, get the screwdriver as close to the alternator as possible without touching any of its moving parts. If necessary, use a pair of pliers or another tool to hold the end of the screwdriver so that it does not come into contact with anything other than the alternator. Then, turn on your vehicle’s engine and listen for any unusual noises or sounds coming from within the engine bay.

Bring the Screwdriver Near the Alternator

To start, bring the screwdriver near the alternator while your engine is running. The first thing you will notice if your alternator is working correctly, is that there will be a magnetic pull on the screwdriver. This means that there should be enough power being generated by the alternator to create this magnetic field.

If you do not feel any pull from the screwdriver, it may indicate that there are problems with your alternator. Another symptom of a faulty alternator includes dimming headlights when driving at night or low battery voltage readings on your dashboard.

Ensure Safety Precautions

While delving into how to test the alternator with a screwdriver, it is important to note that safety precautions must be taken seriously. Working with electricity can be dangerous and potentially lethal if proper safety measures are not observed.

To ensure maximum safety when testing an alternator with a screwdriver, start by wearing appropriate personal protective equipment such as rubber gloves and eye protection. Secondly, disconnect the battery’s negative terminal cable to prevent electrical shock or damage to your vehicle’s electrical system. Once this is done, locate the alternator on your car engine and inspect all wiring connections for any loose wires or corrosion that might impair accurate readings during testing.


If you can learn how to test the alternator with a screwdriver it can save you time and money in identifying potential issues with your car’s electrical system. It is important to follow the proper safety precautions and steps to avoid any accidents or damage to your vehicle. By using this simple method, you can quickly determine if your alternator is working properly or needs to be replaced. Remember that regular maintenance and inspection of your car’s parts can prevent costly repairs in the long run. Don’t hesitate to try this DIY test on your own, but always seek professional help if needed. Stay safe on the road and keep your car running smoothly!


How Do I Test My Alternator Manually?

The first step in testing the alternator manually is to check for voltage output using a voltmeter. You will need to disconnect the negative terminal on the battery before testing. 
Start by switching on the engine and setting it at idle speed; then connect the voltmeter’s positive lead to the battery’s positive terminal and negative lead to any metal part of the vehicle chassis or engine block. If the reading shows between 13-15 volts, this indicates that your alternator is working correctly.

How Do I Test My Alternator To See If It’s Working?

There are a few simple steps you can follow to test your alternator and determine whether or not it is working properly. Here are some tips:
[1] Turn off the engine and disconnect the battery’s negative cable. 
[2] Use a multimeter to measure the voltage output of the alternator. Set the multimeter to DC volts and connect it to the battery terminals.
[3] With the engine off, you should get a reading of around 12 volts from your battery alone.
[4] Start up your car and rev up the engine a bit while observing any changes in voltage on your multimeter.
[5] If you see an increase in voltage readings on your multimeter (ideally around 13-14 volts), this indicates that your alternator is working correctly.

Will The Car Start If The Alternator Is Bad?

In simple terms, if your alternator has completely failed and isn’t providing any power to the battery, then chances are your car won’t start. The starter motor relies on the battery for initial power to turn over the engine. Without that starting power from the battery, you’re left with nothing but silence when trying to turn on your engine.