EdupradaIt is difficult to determine whether the alternator or the battery supplies electrical energy to the battery.
In this article we will explain to you how to test an alternator and a battery to be able to easily determine which of the two will need to be changed! alternator should be changed when you encounter a failure during startup. These two parts are also closely linked because the
How do you know if the battery or alternator is out of order?
Your car won’t start? This could be the fault of the battery… the alternator… or even the starter. Nothing is certain.
The battery light stays on on the dashboard? Same problem: this could also be a sign that the battery is malfunctioning or that the alternator has failed. To ensure that it is the alternator that needs to be changed, there is only one solution: test it.
How to test your alternator?
It is very easy to test the condition of your alternator.
Step 1: Connect a Voltmeter
Connect a multimeter to voltmeter position, or a simple voltmeter. Connect the red lead to the positive terminal of the battery (large output terminal) and the black lead to the negative terminal.
Step 2: Start your engine
Once the device is plugged in, start your vehicle’s engine without engaging the choke and without accelerating. Then accelerate and note the values displayed by the multimeter.
Step 3: Verify that your alternator generates 14 to 16 Volts
Your voltmeter should display between 14 and 16 volts. If this is not the case, your alternator is defective and must be changed.
How to test a battery?
There are several techniques for testing your car battery: using a voltmeter, using a probe or even using a probe but by starting your car. Here we will explain to you how to start your car using a voltmeter!
Necessary material :
- A voltmeter
- Protective gloves
Step 1: Stop your car
To start this test, you will have to turn off the ignition of your car. Once the ignition is off, identify where your battery is located and remove the cap from the positive terminal of your battery.
Step 2: Plug in the voltmeter
To test your battery, now take a multimeter in voltmeter mode or a voltmeter, and choose the 20v position. Then connect the red cable to the “+” terminal, then the black cable to the “–”.
Step 3: Start your engine and accelerate
Once the connections are made, start your engine and accelerate up to 2,000 rpm. If the voltage measured by the voltmeter is greater than 13.2v, your battery is working perfectly. If this is not the case you will have to go to a mechanic to have your battery checked!
If your car won’t start
If your car does not start and you therefore cannot carry out the previous operations:
- Park another car next to it;
- Keep it lit;
- Make the connections using jumper cables: the end of the red (+) cable to the plus (+) terminal (the thickest) of the discharged battery , the other end of the red cable on the plus (+) terminal of the donor battery and the end of the black cable on its minus (-) terminal;
- Start the car to be repaired;
- Unplug everything;
- Drive at least 20 minutes or ten kilometers to fully recharge your battery;
- Perform the two tests described previously.
And there you have it, you know the difference between an alternator problem and a failure of battery. Knowing these parts better and understanding how they work and how to test them will help you get out of any situation!