Will a Car Start With a Bad Alternator

If you’re like most people, you’re probably worried about your car’s battery. You might have heard that a car’s alternator is sometimes the first thing to go, and you don’t want to be stranded on the side of the road with a dead battery. Well, here’s what you need to know about car alternators.

Alternators are basically electric motors that help your car move. When your car’s battery goes down, the alternator will start working to keep the vehicle running by spinning around and generating electricity from the engine. If your alternator does go bad, it might not be able to generate enough power to keep your car running. This can lead to a dead battery, so it’s important to check your car’s alternator regularly and replace the unit if it starts producing low levels of electricity.

What is an Alternator?

An alternator is a device that converts mechanical energy into electrical energy to start your car. When the battery is low, the alternator helps to keep the car running. The alternator can also be used to recharge the battery when it’s not being used.

How does an Alternator work?

An alternator is a device that converts mechanical energy from a engine into electrical energy. When your car’s battery is running low on power, the alternator kicks in to provide supplemental power. If your alternator is not working correctly, it can cause your car to not start.

What are the symptoms of a bad alternator?

If your car fails to start, there’s a good chance that the battery is low on juice and the car won’t start because of the alternator. A bad alternator can cause the car to not turn over at all, or it may only turn over when the battery is completely drained. The alternator output voltage will also be low, which will cause a noise in the engine. Here are some other common symptoms of a bad alternator:

-The car will not start
-The car will only start when the battery is completely drained
-The alternator output voltage is low

How to test your alternator

When your car won’t start, the first thing you should do is check your battery. If it’s fully charged and the car still won’t start, there’s a good chance your alternator is bad. Here’s how to test your alternator:

1. Remove the battery cover. Make sure you have a voltmeter and know how to use it.

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2. Place the voltmeter on the black (negative) terminal of the battery. Connect the red (positive) lead from the voltmeter to the alternator output. Turn on the engine and let it run until it stalls. Record the voltage reading at this point.

3. Repeat steps 2 and 3, but this time connect the voltmeter to the white (positive) terminal of the battery. Let the engine run until it stalls. Record the voltage reading at this point.

4. Compare your two readings and determine which one is higher. If the voltage reading at step 3 is higher than that at step 4, your alternator is probably bad and needs to be replaced.

How to Fix a Bad Alternator

The car is not starting. The battery is good and the lights come on, but the engine just won’t turn over. It’s probably time to check the alternator.
There are a few things you can do to check an alternator before you take it to a mechanic. One of the most common issues with alternators is a bad connection between the output and input wires. Here’s how to check if this is the problem:

1) Turn off all the electrical accessories in the car, including the power steering, air conditioning and any other devices that use electricity. This will isolate the battery and alternator from each other.
2) Remove the cover over the alternator by unscrewing two screws on either side of it. You may need a Torx bit to remove them.
3) Check for continuity between both output (red) and input (black) wires using a voltmeter. A good connection will show a reading of 12 volts or more. A bad connection will show a reading of less than 10 volts. If there is no continuity, replace the alternator.
4) Reconnect everything and test the car again. If it still doesn’t start, it.


If your car is not starting, there is a good chance that the alternator is faulty. This device supplies power to the car when it’s running out of battery and needs to be replaced as part of your routine vehicle maintenance. If you’re experiencing issues with your car not starting, it might be worth taking a look at the alternator to see if it’s causing any problems.

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