Motherboard checking with a multimeter is a technical task, but if you are handy, you don’t need to hire a professional to do this job. The motherboard is just like the mother in the family. It is the mother of all boards on your computer runs the system. You can say it is the brain of your computer. It leads to significant parts of your computer. If your motherboard has some circuit issues, it may not perform well in some instances. If you face this type of problem, don’t worry; you can fix it at home.
You need to learn how to test motherboard with multimeter at home. It is a convenient way to solve this problem at home. You just need to test all circuits by the multimeter. If you feel something is going wrong with your computer, you need to test or may motherboard troubleshoot. Troubleshooting is also an essential part of owning any device and system.
What Is Multimeter?
It is an electronic tool used to measure the instrument’s electrical properties. A typical multimeter can use to measure voltage, resistance, amps and current. It’s beneficial in situations of testing short circuits.
If you don’t have one, don’t worry, it’s not much expensive. You can buy it for under $50. It can be helpful for motherboard checks to avoid more significant trouble. You can call it a digital multimeter checker for motherboards.
2 Methods to Test Motherboard with Multimeter
These two straightforward methods will help you test the motherboard components with a multimeter. Follow these steps to test the mobo/motherboard of your laptop and computer:
The first method I’m going to talk about is a short circuit in the motherboard. It is the most common problem with the motherboard that everyone is facing. You can test the motherboard has a short circuit problem or not by following these steps:
- You first have to shut down the computer entirely and unplug the power supply and other connected components.
- After turning it off, wait for a few minutes to cool it down properly, then make sure it has no charge. Don’t be hasty to move on to the next step. Make sure you wait for a couple of minutes to move further.
- Now take your multimeter and set it on the lowest, usually 200 ohms. Then bring down the meter to zero and touch both leads together. Now it’s time to do the test with a chassis, whether it comes on zero or not. Just do this for your safety.
- Disassemble your computer to separate the motherboard when done with these things. Then remove the ATX connector from your motherboard.
- Connect the red lead to the Ac ground pin on the PSU, and the black lead must connect to the chassis. And the Dc connector has black wire pins. And their readings must be zero at that time.
- Make sure the black lead is in its place, then use the red lead to check the colored wires. You may have to check the reading that must be 50 or more commonly. If they blow 50, this matter is alarming.
- If you are not satisfied with the above steps, you can use other methods or techniques. After removing the motherboard from your computer, use the ATX-20 pin chart to find the motherboard pins. You can use red lead to test the pins. If you see the reading is zero, everything is fine, but it will be an issue if you see something else.
It is the first way to check motherboard with digital multimeter. Let’s check out the other method.
2) DC Voltage
These steps may be slightly different from the first one:
- You should know that ATX-20 must be connected, and the computer is turned on.
- Set your multimeter settings on 20V DC.
- Test the rear side of the connector by using a black multimeter test. You should set the black test in contact with 15, 16, and 17 pins for doing this.
- Now test the pins 9 and 14 with the red test. Pin 9 reading should be 5V, and pin 14 must-reads between 3 to 5V.
- If the reading drops to zero, you have to turn on the computer because everything is fine. If readings are not zero, there must be an issue that you must resolve.
- Do the red test again for checking pin 8. Its ideal reading is 2.5V. Press the reset button to see that the readings go down, back, or remain the same. If you are not handy, you can hire a local professional to do this job for some bucks.
Let’s talk about some additional ways to test motherboard components with multimeter:
How to Test a PSU with the Motherboard?
If you are worried about how to test a PSU, here is the solution:
- Unplug the computer from the power connector and other components. After that, wait for a couple of minutes to cool it down. Now set the multimeter on minimum settings and contact the leads to zero on the meter. Touch them to the bare metal chassis to make sure the reading is zero.
- Remove the ATX connector from the motherboard. Keep the black side on the chassis and red lead to check the ground AC pin. If they are at zero, there is no issue. Otherwise, it will be an issue.
- Now check the shaded wires or DC connector, and their reading must be 50 or more.
- Now remove your CPU from your motherboard. Use the ATX-20 pin chart to refer to the nail number of board connectors.
Test the Motherboard Power
- The first step is to plug the power supply into the wall. And find the big 24-ish pin connector that is attached to the motherboard.
- Connect the green wire with the black adjacent wire if the power supply fan starts. Its means the motherboard is dead, or if not. It means the power supply fan is dead.
Test PC Power Supply with Multimeter
Follow these steps to test pc power supply with multimeter:
- You can wear safety gloves and shoes as a precaution because you may deal directly with voltage points.
- Power off the computer, disconnect and unplug all the connections and main supply, including PSU and CPU data cables.
- Connect the power supply pins 15 and 16 with the motherboard 24 pin.
- Some countries have 115v as a general household, and others have 220v as a general household. Make sure your power supply is adjusted according to your country’s primary voltage.
- Turn on the multimeter, set the voltage to 200 to 300v, and check the following voltage.
- Connect the power supply unit plug with the main outlet supply on the fan inside the power supply.
- After that, turn on the multimeter range from AC to DC volt up to 20vdc.
- Connect the black and neutral lead to the ground point and red lead to the point of 24 pin connector.
- Check every point to make sure that all supply points are working correctly.
- If you find one or more points have abnormal Voltage or missing the voltage output, they have some problem in the power supply.
- First, turn off the power supply of the PSU. Again turn it on or reconnect all plugs. Connect power plugs to PSU and turn on your computer also.
- In the end, turn the multimeter to save the battery. That is how you can test a computer power supply with a multimeter.
Suppose you want to test the capacitor of your computer with Multimeter. Set the high ohms multimeter to range between 10k to 1m ohms. Touch the corresponding lead to the capacitor. The meter moves from zero to onward. It shows red for positive and black for negative.
Set the multimeter on ohms meter settings and place the lead across the two ends of the fuse. If you get the slow readings or few ohms, the fuse is continuous; it’s good. But if you get high readings or high ohms, the fuse is broken and damaged. So it should replace.
You can find that simply just plug the PSU into the functioning system and turn it on. If PSU is not working, it’s broken, not the motherboard.
But if you are using a laptop, plug the Ac adapter into the laptop and on it. If it’s working, that means your motherboard is fine.
Yes, you can test the motherboard without a CPU, but if it has certain features like a post on self-test, it requires LED light for the process and allows you to test the motherboard. But this feature is only available on inexpensive and high-quality motherboards.
If it fails in the test, it is the bad CPU. It may create a beep sound to tell you the problem with the motherboard and CPU. Beeps number is also a code that tells you where the problem is.