How to Check Ground with a Multimeter?

This post contains affiliate links. As an amazon associate, I earn affiliate commission, from qualifying purchases.

Ground checking is used to check hot, neutral, and ground wires and their voltages. All you need to do is, insert the probes and set your multimeter to the utmost voltage setting. Through ground checking, you will find out if the outlet is grounded properly or not. Here in this article, you will get a complete guide on how to check the ground with a multimeter.

What is Grounding?

Most people are not familiar with the concept of grounding. Before starting a testing process, it is important to understand the concept of grounding. The main function of a ground connection is to convey discharged electricity from an outlet or some appliance into the ground. This will keep people safe from discharged electricity.

How to Check Ground with a Multimeter?

Some of the steps that are involved in checking ground with a multimeter are as follows:

Step 1: Set up Your Multimeter

First, set up your multimeter properly before starting the testing process. Set your digital multimeter to an AC voltage mode. For this, navigate toward the settings and set the value. Select the highest voltage value, which will help you get an accurate reading. Similarly, in the case of an analog multimeter, adjust the device’s dial to the V letter position.

Step 2: Attach the Probes

After setting up the voltage value, the next thing is to attach the probes. Every multimeter contains around two different-colored probes, i.e., black and red. Attach the black probe to the port labeled as COM or –, and the red one to the port labeled as Ω, V, or +. One must execute this step properly, as a small mistake can cause a short circuit in your multimeter. Similarly, avoid using cracked or damaged probes as minor mistakes can sometimes lead to major disasters.

Step 3: Check the Reading

In this step, one needs to test the neutral and hot wires using multimeter probes. To keep your body safe and protected from shocks, hold the probes with the help of insulation wrappers and then push the red probe within the live port.

Similarly, take the black one and push it into the neutral port. However, if you face difficulty figuring out which one is the neutral port and which is the live one, check their sizes. The smaller one is a live port, whereas the larger one is a neutral port.

Step 4: Use Earth Port

Now, check the voltage between the live and the earth port. Earth port is usually U-shaped or circular hole. It is positioned at the top or bottom of the outlet. To do this, take the red probe out from the neutral one. Do not disconnect the black probe from the live one in this procedure. 

Step 5: Analyze and Record the Reading

Properly check the voltage reading on the multimeter and keep a proper account of it. If the outlet’s connection is grounded, you will get a reading equal to 5V. However, if the reading is zero or close to zero, the outlet is not grounded. One must properly write the reading they got to compare the result with later values.

Step 6: Compare the Reading

Check the voltage between the neutral and earthing ports of the outlet. While doing this, place the black probe in the earthing port and the red one in a neutral slot. Doing this will show a small number of volts on the device. Compare this reading with the previous ones. This will also help you understand how much electricity travels between the ports.

Step 7: Calculate the Leakage

Do not forget to calculate the total leakage after you get the reading. For this, subtract the first reading value from the second and add the third reading to the total sum. If the total value is more than 2V, the ground wire is faulty and needs to be checked or replaced. However, if the resulting value is less than 2V, then it means everything is safe.

Important Things to Check

Electrical problems normally occur because of bad electrical ground connections. There are many reasons behind this problem, such as noise in the audio system, issues related to electronic engine controls, fuel pump problems, and more. It is necessary to take proper measures to get rid of such issues. Some of the important tips that help people in avoiding these issues are as follows:

Proper Ground Point

Always make sure that the ground wire is attached properly to your vehicle. Consider the point of attachment that is free from rust and paint. Make the connection properly and make sure you have managed things accurately.

Use Accurate Gauge Wires

While selecting the gauge wires, keep account of the wire current. Change the gauge of the ground wire according to the current value. Normally the factory-made wires contain 10 to 12 gauges and are simple and easy to set up and use. If you face difficulty handling things on your own, consider taking professional help.


It is important to check the ground with a multimeter to ensure everything is working correctly and there is no issue with the wiring. Generally, a properly done ground wire will release electricity from things like faulty wire and transmit it to the ground straightforwardly. In case the ground wire is not managed properly, there are chances of accidental electrical discharge. Due to this reason, it is important to have a well-grounded house so you cannot face any trouble later on.

Leave a Comment