Really honest person,trying to explain what’s going on , after finding already problems. Thankful

Happy return teacher, your classes are greatly missed; thanks for the experience and tips, greetings from South America.

You chose the HP because the color matched your shirt. Thanks for today's lesson.

like MOSFETs, Zener diod is almost certainly part of the charging chip design template. Most of the manufacturers implement reference design instead of inventing their own weel. The problem with input voltage protection is that both MOSFETs could be shorted by voltage spike of a malfunctioning power supply. If it builds up a high-frequency AC ripple, it may be overseen by ACDET regulator but it will still blow insulator in MOSFET. in this case, you have uncontrolled DCIN going directly into the main power rail which is always a bad situation. Zener diodes are used on every single HDD as an over-voltage protection fuse - it gets blown very fast and it shorts power rail to the ground. Think of Zener diodes as an over-Voltage fuse. Since you did not replace the Zener and customer will use the same PSU, this laptop might come back at some point and I guess if it will, it will come with a blown cap or VCORE MosFET.

The best teacher I have ever seen.

Not stupid if they want the laptop to "break" easily...

It's not zenner diode, it's reverse polarity protection. See it's pd9, not pz9 and the symbol shows a diode. That's why it is there for reason and not stupid.

"Now I'm angry" ..the way you said it... Loved it! Very educative as well.

I like your way in analyzing and solving each case you come up to, i am addicted to your videos, a week without them OMG

amazing talent you have sir.....I do repair things, but a laptop on this level is something I always wished....

I love all your videos.. I truly admire your generosity in sharing your valuable experience and knowledge. Bless you!

In my PSU designs I use suppressor diodes to protect from spikes, when they fail, fail short and burn out the fuse, so the rest of the board is safe and doesn't stress the charger or whatewer the power source. HP really should put some kind of fuse to the power rails. EDIT: if something goes wrong with the charger or wrong charger plugged in tantalium capacitors blow up pretty agressively. My guess they use max 25V components.

Thank you for being such a good teacher!

Subbed and Thumbs up! Thank you so much for this! I was a repair engineer _Once_ and I still like to think that I can tackle most things but I was presented one of these in a very similar scenario, with the exception that the charging light comes on and it will charge the battery but when the power button is pressed, lights (but no screen) come on briefly; fan spins briefly then everything goes quiet, leaving only the charge light on. PSU is fine but *not* original. One of my excuses to not attempt something like this is that I don't have a Scope or re-ball facilities but you prove the contrary, using tried and tested basic equipment to repair things that would otherwise be 'beyond economical repair' by smaller companies and astronomically high priced repairs from manufacturers.

That part you were pointing out is actually a TVS diode (transient voltage suppressor) marked as "IV". You can look at it's specifications under it's equivalent being SMAJ20A tvs diode. It was a bit tricky finding it as either new semiconductor devices do not have a standardized marking code or, that (somewhat imperialistic) companies have their own marking code which at times do not even correspond to their own data books.

I have repaired my HP Pavilion 15-n225sf , i can't believe this, you are... a master, and i'm as far to be skiled as you are, Thanks thousand times.

Great stuff. I have just bingewatched about 4 hours back-to-back. Thanks.

That stupid zenner diode allows you to have a client =) your videos are fantastic, thanks for sharing your knowledge!!!

Long time no see Master. I've missed you.

Wonderful, I love your videos man, so much to learn from, thanks a million.

Loved this one. thx so much for teaching me

HP designer and his manager disliked the video!

Always love your teachings Sir..thanks you come back...yes i believe hp got a problem as i experienced

keep sharing sir ..this a big help to all beginner like me ..to become someday like you sir

Great video.I agree with your reasoning on the protection diode,which does not really protect but kills your laptop.

Your all videos are full of information Thank you sir Love you

wow... you really cant understand how much you've been a source of inspiration to me. thanks Sir... i really appreciate this

Did the guy with the computer give you the shirt too?😂😂 Love your stuff man.

Excellent work!! Love your lessons.

Thank you Sír you are a great human being for share all of this. I wish I have the 5 dólares to joining your school.

Hope you had a nice holiday Sorin, I was wondering where you was, I missed your videos big man 👍🏻

Very good your point of view HP notebooks, Excellent contribution to knowledge

A very very good explanation, you're the man Sorin !

25:46 where fun part starts :)

Thank you Sorin, I imagined the fault before you show it just because I saw your other videos before ... You're a master in the Power fault !!!

This is a nice one, thanks for nice diagnosis. I am being inspired.

Love the way you teach troubleshooting.

Am grateful for your videos it teaches me new methods

'This is moral thing' Well explained. Thanks Sorin

You are the BEST Sir, it was same on my laptop, GREAT...!!! HP ab203TU ... I solved it looking your lesson.. Thanks again..

Thank you so much for today lesson!

Wonderful, I like your enthusiasm

Good job Mr. i m learning a lot

Welcome back ,nice to see you again.

He kinda looks like a grandpa teaching his grandchild with so much care and devotion. 💓💓💓

Welcome back Sorin we miss you Thank you for the nice video

i have a limited electronic education but you explain so good i can understand .

Hello thanks for sharing your experience. After you remove the zenner diode you had to put a bridge wire at it place right?

happy to see you Sorin :) we missed you

felicidades maestro y gracias por la leccion. see you next one thanks

very helpful to our friends ,, all of you are very kind

now I am going to look for zener fusible diodes right beside a capacitor....ACER ASPIRE 5333 water came out from ceiling it got poured and now hard to think more possible solutions. Thank you for sharing another idea!

started more liking for your lessons and a style of teaching too. very informative. Thanks

I so much love the way you teach... I wish I could be your student.

31:05 haha what is that someone put coin in USB port ? :O will that make laptop dead ? Respect! i learned so much from you and every day learning working with laptops 20 years and still every day I learn something new from you ! God bless you!

Thank you sir! I learned a lot from you.

It may be a Transil diode called also TVS (Transient Voltage Supressor). It is used to protect against overvoltage. It shorted itself but protected rest of the components. In some cases transil can even protect against catching fire or explosion of Lithium-ion batteries.

Amazingly intelligent man I wish i was half as smart as you Sorin. Your videos brighten up my day!

very cool technician you are ,following since TOGO

Thanks for the great video. I removed the zener diode but still the PC wont start and no power led lighs up. Voltage over the zener diode when removed is 19,9 volts when you had 0,5 volts..so obviously there is another problem right?

Sorin, they got you back just to fix all the unfixable ones. Admit it!

I fall asleep from your calm explanation that I cannot follow it, you are the master of electronics

God bless you for today’s lesson ❤️🙌🏽

nice work sir I learn something in this video

Thanks so much for this nice and clear video!!! I would like to have your thoughts about a laptop HP envy i7 17" I have which does not charge the battery when it's ON and charge it when power is OFF. power supply has the light, when the battery is charge everything works. I tried to remove the battery and power ON but apparently this laptop needs a battery to power ON. thanks for your answer.

very clear sir! and thank you for the lesson yeah!

Welcome back! Wanted to ask, can you show how to diagnose if a hub is dead? Thank you!

Sorin, your shirt matches the laptop!

you inspire me and i think your job is pretty cool i have a similar problem but the super I/O (ITE chip) is getting hot and i dont have a voltage measure device

capo total la manera de explicar es sensacional soy de argentina y entiendo mas con vos que con los de mi propios idiomas

Great work Sorin, thank you

I should call you "Master"! It really helped me a lot. thx!

i missed you man, the guy from South Africa.

thank you for New video sir.. Miss you

Thanks so much and your videos has helped me a lot and I were able to fix my Boss's Hp laptop - Probook as the Ram slightly came loose. And I had to open it up and pulled out Ram chip and replaced back into the board and then the laptop powered up and operated after experiencing screen freeze and only lights blinking within the keyboard area,,,. And now I need to fix my friend's Hp ProdID 250 G7 laptop but haven't seen one video of it as yet, and if someone able to show me and I would very much appreciate that,,,,. Regards, Charlie Jay, Wabag, Enga Province, PNG.

wow, best ever video on repairs you are truly a genuis🎉

It’s a great repair again And indeed the blue case is matching

buna, frumos dom profesor, apreciez munca depusa.

thanks mr sorin,you're my teacher. i get a lot money from your videos

You are amazing man Thanks for o lot of hints and I recovered a HP Laptop coz of you.

you have to come together with Louis Rossman :)

you are simple to follow keep up the good work

Learning a lot from you . Thank You

Helpful video 👍

Sorin I wanna know something. Now whoever is sending you those laptops to you for reapirs, ( you said its from another shop) are those people or that guy not watching your videos and learning to troubleshoot? Get my point? By the way thanks so much once again. Love. Good luck. 😊 You are a man of 'heart'.

Hi Sorin what if I dont have linear power supply and i inject maybe 5v 2a through the pwr resistor can I find short with this method or I need higher voltage?

happy to see you again !

Thank you for the lessons

I Recived this laptop on my shop same day this video was Published, and you know what? Same problem, i think i owe at least a Coffee to Sorin! :D THanks!

Awesome channel. Godbless you sir.

Your a flipping credit to watch. Unreal. Good luck and health to ye. Lorcan here in Ireland

Thank you very much for your lesson. You are a great teacher.

I have the same motherboard and I removed the zener diode as I had the same symptoms, I now think I also have a blown mosfet M3016D the big mosfet in this video below the zenor diode with 3 legs, is it safe to bridge this mosfet or would it be safer to get a replacement M3016D mosfet, thanks, P.S love the videos I am learning more each day

I didn't learn anything but thank you so much for sharing your knowledge because I'm not interested in laptop repairing but on the other hand it is a big service for the people thanks again.

Excellent, compulsive viewing ! The TV is dead !!! Great entertaining show !!

Man I don't watch 5he Visio very good because I have no time but you have a nice work keep it up

You are the best man love your'e video's I learn so much from you thanks man

Thank you sir for the great teaching. sir if a hp laptop is not powering and the charging light is showing please what is the solution?

Fascinating! Thank you! As an application software support programmer, I find similar stupid things that programmers do in their programs. At least half or more of the programmers have no business writing programs. 90% of programs are terribly unstructured, disorderly, and inefficient. 10% of them are quite elegant and are a pleasure to read and follow along. The "logic" in circuitry is very similar to the "logic" in software, and most of the time, there are problems with insufficient testing and a lack of consideration for the end user's perspective.

I think its a TVS diode. A transient voltage suppression diode. It will short if the voltage reach its limit and does not recover from short anymore. I found one in a Western Digital Hard drive and its the same problem, the area where it was located we're charred/burnt.