The Fastest Way To Detect Short-Circuit On Laptop Motherboard - Laptop Repair

[@Djazeiry]

your videos are getting better and better dude just keep going because you're...unique

[@electronicsrepairbasics_erb]

Thanks, will do!

[@joe1692]

You are doing such a great job with your videos !!!! Each one keeps getting better.

[@electronicsrepairbasics_erb]

Thank you so much!

[@justinl.3317]

Everyone bragging what a great video, What was left out, was whether to repair the area of shorts, or just trash the motherboard. Appears to me there were MULTIPLE Shorts all throughout the section!

[@garypoplin4599]

3:06 - If you were to test your meter leads by connecting the other probe to a different point on that ground pad, you would verify the first probe connection as well as the integrity of your meter leads with a single test. Then move the other probe to your test points with confidence of a solid connection to the first probe for accurate readings.

[@0xggbrnr]

One of the best videos i have ever seen. Thank you.

[@b.manoharan9456]

Dear sweet heart This is b manoharan from India, tamilnadu state, Namakkal districts. Am an professional electronic engineering guy... Your technical tips is very nice 👍🏻 in understanding in a simplified... Direction am waiting/ following your videos Pls explore more related to this chapter... Nice 👍🏻 gentlemen... 👍🏻👍🏻 ❤️❤️ 💪💪 🙏🏻🙏🏻🙏🏻

[@ministeriomundialliberando8403]

One clue to determine if it is a short or low resistence is to check both side of a capacitor in te circuit, since one side of it shoud be connected to geound but not both, if it is, for sure there is a short circuit.

[@stalwartekwere2157]

Nice job.... your a good teacher 👍

[@electronicsrepairbasics_erb]

I appreciate that!

[@surgingcircuits6955]

Very Useful! TY!

[@electronicsrepairbasics_erb]

Glad it was helpful!

[@ppafan]

Very comprehensive video, great job. Can you also make video on voltage injection to find fault

[@electronicsrepairbasics_erb]

Noted

[@uttamx2016]

and also where do need to inject voltage to detect short

[@ravindraadapa2952]

Bro i know you are a good tutor the video was very good for learning but as we found shorted directly to ground through coil getting low resistance but how to find exactly which components are short in that section particularly is there any way alternative like to injection of low voltage with some amps of current is it possible to please make a video on that section to find exact short tq

[@laptopguy2230]

very nice please do one video on voltage injection. Thank you

[@electronicsrepairbasics_erb]

Ok. Thanks

[@francesco6016]

Hi, is there risk of frying components using the multimeter? (i.e. applying too much voltage or current using a given setting) Many thanks and great video! Cheers from Italy

[@nessim.liamani]

The method described by the KZbinr, testing **inductors in diode mode** to check for short circuits to ground on a motherboard, is a common and effective technique in electronics troubleshooting. Let me break it down and provide my take on it: --- ### **What Is Being Tested?** 1. **Inductor as a Test Point:** - Inductors in power circuits are directly connected to critical power rails, such as **VCC_CORE**, RAM voltage, or GPU voltage. - By testing the inductor, you're essentially probing the power rail for abnormalities like a short circuit. 2. **Diode Mode Testing:** - Multimeters in **diode mode** measure the voltage drop across a component when a small current is passed through it. - When one probe is placed on the inductor and the other on ground, the reading can indicate: - **Normal behavior:** A standard forward voltage drop (~0.4V to 0.7V) caused by components like MOSFET body diodes or capacitors charging. - **Short circuit:** A very low reading (close to 0V), indicating the power rail is shorted to ground. --- ### **Why Inductors?** - **Accessibility:** - Inductors are often exposed on the PCB, making them easy to probe without desoldering components. - **Direct Connection to Power Rails:** - Since inductors are part of the DC-DC voltage regulation circuit, they are directly connected to key power rails. - **Quick Diagnosis:** - A shorted inductor quickly narrows down the issue to the corresponding power rail or its downstream components. --- ### **How This Method Works** 1. **Set Multimeter to Diode Mode:** - Place the black probe on ground (negative terminal) and the red probe on one side of the inductor. 2. **Interpret the Results:** - **Normal Voltage Drop (0.3V-0.7V):** - Indicates normal operation. The voltage drop could be from MOSFET body diodes or capacitors charging on the rail. - **0V or Very Low Voltage (~0.01V-0.2V):** - Suggests a short circuit between the power rail and ground. 3. **Repeat for the Other Side of the Inductor:** - If both sides show a short to ground, this confirms a shorted power rail. --- ### **Advantages of This Method** 1. **Non-Invasive:** - It doesn’t require removing components from the motherboard, saving time. 2. **Quick Identification of Faulty Rails:** - Testing inductors quickly isolates the problematic power rail. 3. **Effective for Short Circuits:** - Shorts to ground are one of the most common failures on motherboards, and this method efficiently detects them. --- ### **Limitations and Potential Issues** 1. **False Positives:** - Some power rails, especially those with **large capacitors**, may initially show a low reading as the capacitors charge. This could be mistaken for a short. - Body diodes in MOSFETs can also cause low readings, even without a short. 2. **Limited to Power Rail Shorts:** - This method only detects **shorts to ground**. If there’s an open circuit or a fault elsewhere in the rail, this test won’t identify it. 3. **Advanced Circuits:** - Modern motherboards may have rails connected through **ferrite beads** or **protection diodes**, which might alter readings and require further confirmation. 4. **Requires Confirmation:** - If a short is detected, further testing is needed to pinpoint the faulty component, such as capacitors, MOSFETs, or the CPU/GPU. --- ### **How to Improve the Method** 1. **Use Resistance Mode for Confirmation:** - If the diode mode indicates a short (0V reading), switch to resistance mode to measure the actual resistance. A true short will show a very low resistance (close to 0Ω). 2. **Thermal Camera or IR Gun:** - When a short is detected, injecting a small voltage (e.g., 1V-5V) into the rail and using a thermal camera can help locate the faulty component by identifying the area heating up. 3. **Inspect Nearby Components:** - Focus on capacitors, MOSFETs, and other nearby components directly connected to the inductor, as they are the usual culprits. --- ### **Conclusion** The method of using diode mode to test inductors for shorts to ground is a simple, effective, and widely used technique in motherboard repair. However: - It is best used as a **first step** in diagnosing issues with power rails. - Additional testing (resistance measurement, thermal imaging, or component isolation) is often required to confirm the faulty component causing the short. If you follow this approach methodically and verify the results with other tools, it can save significant time in identifying short circuits on laptop or desktop motherboards!

[@Ethioit1]

very good lesson but you should tell us which component is shorted in the cpu circuit

[@eshan1132]

Thank you so much for good explained

[@r_man-o5o]

thanks a lot for making this type of video.

[@electronicsrepairbasics_erb]

It's my pleasure

[@waiyan-b6w]

Lenovo IdeaPad 300 power supply amp 35 still while where checking part, sir

[@VicsMedia-jy3ly]

Many and sincere thanks for sharing !!

[@victorobikenwabusis]

you made it very easy to understand

[@johndietz1266]

Yes he did

[@zoedubois800]

Hello if the short circuit is in the cpu how to remove it

[@electronicsrepairbasics_erb]

By changing it

[@surgingcircuits6955]

I must admit that removing the CPU or like, and getting a higher resistance is baffling me a bit. Seems like it would remove resistance. Is it possibly because capacitors supporting the chip are drawing current from the DMM during testing? Or other? Thx.

[@electronicsrepairbasics_erb]

Keep in mind that the resistance of all chipsets including CPU are low in every motherboard.

[@surgingcircuits6955]

@@electronicsrepairbasics_erb ...yes, agree, but seems like we're adding more wire ... although very small. Thanks for your video and response.

[@898orion]

Thanks great video! I learnt a lot.

[@Fixtjub]

If I am injectimg the voltage, can i use ground and coil to inject it ?

[@johndietz1266]

Just use voltage coil

[@claytonbennett7797]

You said a low resistance is bad - what qualifies as low? For all of my inductors I'm getting a low of 300 ohms. Saw 50 ohms on one.

[@leroux-ianni]

Your lucky, I saw 3 ohms on my motherboard 😮

[@johndietz1266]

It depends on the application

[@laurenttosh5655]

Hello, is a 20 Ohm resistor a short circuit ? THANKS !

[@johndietz1266]

Depends on the application

[@johndietz1266]

It depends on the application

[@borujawi5629]

great work! and very crucial title , you found region where short circiut is take place but how we can found excact component(s) wich make short may inductor,capacitor ext..?? thanks so much

[@electronicsrepairbasics_erb]

Yes, you are right

[@ENGMOHAMEDMOSFET]

From Somalia 🇸🇴 🎉

[@electronicsrepairbasics_erb]

You are very welcome

[@VicsMedia-jy3ly]

Which side should be checked ?

[@ziadfawzi]

Thank you so much.

[@electronicsrepairbasics_erb]

Always welcome

[@smca7271]

Are you saying inductors?...or meaning semiconductor?

[@riazrehman8941]

Mery pas laptop hai usme ye problem hai k laptop ko charger connect karta hon to laptop off ho jata hai phir on ho jata hai asay hi on off on off hota hai charger bhi change kar k dekha hai please reply

[@Rams_hobby]

nice, thanks

[@electronicsrepairbasics_erb]

Thank you too

[@Lcs274]

Thanku sir

[@lvwilb5687]

GREAT JOB. HOW DO YOU INJECT VOLTAGE TO FIND SHORT CIRCUIT .

[@electronicsrepairbasics_erb]

The voltage injection is the easiest way to spot a short circuit. Voltage injection occur on the shorted component

[@kgerakopoulos]

1v and starting with 2amps

[@Fixtjub]

CannI inject voltage to ground and coil ? I am not sure where to put + ​@@electronicsrepairbasics_erb

[@restingroysurong805]

Mean all the component are bad ? So explain clearly sir

[@electronicsrepairbasics_erb]

Not all of them are bad, just one is bad and infects the others

[@restingroysurong805]

So if we remove the bad one there is no buzer or beap sound coming again. Please explain sir so that I will try my own

[@candrmix]

So how to know which component caused short??

[@electronicsrepairbasics_erb]

Using many methods that I shared in many videos, for example by checking what component becomes hot, etc

[@nuwanasanga7222]

It's a very good video, but if you can please use the new type (generation) motherboards to explain, you are using very old motherboards, I think that's useless ...👍

[@dombarton2483]

Please use modern boards. You cannot remove cpus from modern boards. I have asked before that you should actually do proper troubleshooting from beginning to end on modern boards. This would be very helpful.

[@electronicsrepairbasics_erb]

It's not about old or modern boards, but about understanding how things works, Regards

[@christiannolan8333]

@@electronicsrepairbasics_erb So if the CPU is not removeable, how would one know if the low resistance is from the CPU or from the circuit itself? I think that is what Dombarton is trying to figure out, including myself -). Btw I really enjoy the content on your channel , it's extremely helpful.

[@shenidan2023]

He's made a great video so stop slagging him down. I am be grateful he has gone to a lot of effort to impart his knowledge

[@hardkore360]

​​@@christiannolan8333easy, lift one leg of the phase inductors (coils) and then you easily isolate the CPU from the rest of the circuit

[@WickyOdongo]

Clear ilastrated

[@jobertgutierrez5788]

I dunno, maybe this is just me, my ears hurt due to the mic eq, the high frequency is to high. but cool vid

[@Arush66]

🤣 same

[@alinaseer6261]

Sir i am need work please help me plzzzzz

[@jameswatters9592]

Where's Cato Fong inspector?

[@hazemeldemrdash2284]

great

[@electronicsrepairbasics_erb]

Thank you

[@KaccemKaccem]

انت تقوم بيعمل تقني 3,3v

[@KaccemKaccem]

Subw sur

[@BM-oz2cd]

Mghribi?

[@joshygaminghub7428]

so lets remove the CPU okehh? lets connect the black to the ground okehhh?

[@meangtongmey8651]

❤

[@seralvplyr]

I don'tYFY Lol

[@KaccemKaccem]

لوحا ليوم 3,3

[@electronicsrepairbasics_erb]

??