Had the exact same fault on my old T470. This laptop actually charges from both the 20V charger and the USB-C port. The Lenovo port is one power rail (before the first two mosfets), the USB-c is the second power rail (before its two mosfets) and after the 4 mosfets is your "main" 19V powerrail, which then creates the 12,7V powerrail. Mine had a shorted capacitor on the rail after the 4 mosfets. Took me about 1-2hrs to figure it out since i didn't have a thermal camera or a power supply at the time of attempting this repair.
Another very beautiful laptop repair and clear explanation! Always pleased to follow your videos and voice! Best Teacher Ever! Grazie di Cuore! Multumesc din tot sufletul!
It's no coincidence that what Sorin posts is what I get that week for repair, happened a lot to me and your help is greatly appreciated, Thank you GrandMaster Sorin
Hi sorin, thank again for your quite and clear explenation lesson made with passion, and thank you toshare your passion, bye Francesco Timpano from Florence Italy
I have a t420 the old one when I press power button it comes on but not like normal (like most of the lights that normally come on don't come on) then turns off same time and power button light keeps going on and off. Nothing else happen. 20v power rail is present that's all I check so far.
Despite the ability of the mosfets to carry high current they still get short, btw do you test how much current can the proper calibrated fuse carry before it gets burned? lol i made few "pcf" with different current rating based on the test i made on the psu, they won't replace a real fuse anyways
Hi mr SORIN, Thank you for all ...please if it is possible,can you zoom in when you check components with the probes because sometimes its hard to tell what component checked ! Thank you again.
I just watched this again, learning from Sorin videos, I am confused .. why is main power rail only 12v when have 19/20v at charger? If motherboard removed I would be thinking something is wrong... 🙂
Well done. My questions are 2 if you don't mind: what is the model of the thermal camera and the microscope you are using? And possibly from where you found them? Most probably I do not find these in my country so would have to order them from another country. If from USA the duty here is way too high for me to afford and now I'm retired. Thank you. 👍
Man love your woek!!! Wish you can help me troubleshoot a Sony oled tv issue with 4 blinking red lights !! Replaced power supply and mainboard still have same issue :(z…
By the way boss u did check on the board by the time you remove the mosfet but u did you just change the without checking the mosfet u been removed coz if u remove a short component u need check by time u remove it but u didn't check the short mosfet but u just replace the other good mosfet
It's a thinkpad thing, with 2 separate batteries you can carry one or few of spares and never turn off laptop while you replacing it, Internal act as an UPS and last resource
Ive noticed Sorin no longer uses "Diode Mode" on his MM to find shorts, he, 100% of the time now, uses resistance mode. What changed ? Just curious. . . . .
He mentioned in a video years ago that diode mode can lead to "false positives." He then proved it with a demonstration and a handrawen diagram to further explain. That's why he uses his power supply (faster diagnosis) to find shorts/overheats alongside the MM,thermal camera, and alcohol tests. Side note: He used to also use the customers charger to power the board initially, but in one repair, the charger was bad, unbeknownst to him, which led to a bloated repair time. So then he started powering the board with his power supply.
yeap , but who cares ? you just a saw a blown fuse with first mosfet burned caused by a a shorted capacitor ...so fuse was improper by default second , you're right, there should be solder a calibrated fuse and more than that fuse must be rapid , wire is a slow fuse !
If the last digit of first number on mosfet is odd then it is PNP and Even number is NPN In this video the first number is 7121 .so last digit is 1 is odd and PNP mosfet
@@italianofx OK but what about names ending in consonant? For example: "DA21DT FDPC 5018SG" Do I take into consideration the last number from the top line (1)?
Had the exact same fault on my old T470. This laptop actually charges from both the 20V charger and the USB-C port. The Lenovo port is one power rail (before the first two mosfets), the USB-c is the second power rail (before its two mosfets) and after the 4 mosfets is your "main" 19V powerrail, which then creates the 12,7V powerrail. Mine had a shorted capacitor on the rail after the 4 mosfets. Took me about 1-2hrs to figure it out since i didn't have a thermal camera or a power supply at the time of attempting this repair.
Did you fix it? Still cool that you can troubleshoot the mobo and find the faulty components!
@@j.lietka9406 I did! I removed and "replaced" the capacitor.
@@express496 cool! Thank you 🤓
@@express496 did you say hello to your little friend?
Another very beautiful laptop repair and clear explanation! Always pleased to follow your videos and voice! Best Teacher Ever! Grazie di Cuore! Multumesc din tot sufletul!
It's no coincidence that what Sorin posts is what I get that week for repair, happened a lot to me and your help is greatly appreciated, Thank you GrandMaster Sorin
Hi sorin, thank again for your quite and clear explenation lesson made with passion, and thank you toshare your passion, bye Francesco Timpano from Florence Italy
Nothing good to wakeup on a Sorin repair video 😊
We have a picture, that is crazy“. Nice Job Sorin
Hi! Bro and everyone it’s very hopefull and amazing presentation you always passionate bro.
finally! a proper calibrated fuse
Me parece maravilloso su contenido y la forma en la que explica todo, soy nuevo suscriptor pero fiel, dejando like a cada video que voy viendo.
Words I need to hear today.
Proper calibrated fuse
and we have picture 😁
very nice sorin... proper nice fuse😅😅
thank u i appreciate u the way u easily solve problem
Yes Sorin, the mosfet is still burn. Lol
I love Sorin!
akurat odcinek do kawki ;)
🎉I learnt a lot My tutor 🙏🏿
Lucky costumer and 2 pizzas for u and Diana🍕🍕💪🏻
Thank you for the vidéo, I would like to know why not replace another capacitor.?
Thank you sir ❤
I have a x250, pretty similar 5th gen laptop. Little smaller than that one. Good to know.
Good job mate 👍
Lets checking on L490 power checkup and everything
Ah, a Hungarian customer.
Biztos
perfect job
I have a t420 the old one when I press power button it comes on but not like normal (like most of the lights that normally come on don't come on) then turns off same time and power button light keeps going on and off. Nothing else happen. 20v power rail is present that's all I check so far.
hello sorin, i still find it challenging to differentiate between N-type and P-type musfet
Despite the ability of the mosfets to carry high current they still get short, btw do you test how much current can the proper calibrated fuse carry before it gets burned? lol i made few "pcf" with different current rating based on the test i made on the psu, they won't replace a real fuse anyways
Please how to identify a P or N channel mosfet as you did?
Hi mr SORIN, Thank you for all ...please if it is possible,can you zoom in when you check components with the probes because sometimes its hard to tell what component checked ! Thank you again.
I just watched this again, learning from Sorin videos, I am confused .. why is main power rail only 12v when have 19/20v at charger? If motherboard removed I would be thinking something is wrong... 🙂
A proper laptop with an external easily replaceable battery! 😎
Respect
If I want to be like Sorin what kind of courses should I take at the uni?
Nice proper calibrated wire 😅
Well done. My questions are 2 if you don't mind: what is the model of the thermal camera and the microscope you are using? And possibly from where you found them?
Most probably I do not find these in my country so would have to order them from another country. If from USA the duty here is way too high for me to afford and now I'm retired. Thank you. 👍
I have the same question as well
Man love your woek!!! Wish you can help me troubleshoot a Sony oled tv issue with 4 blinking red lights !! Replaced power supply and mainboard still have same issue :(z…
how can you tell whether a mosfet is p or n chanel?
Just take the fuse from 7:30, proper calibrated wire.
Nice one
We haaave piiictuureee ,... dat's kkraazyyy you should put this line on your home page picture ... :)
Hello🤝good job 👍👍👍👍👏👏👏👏👋👋👋👋
By the way boss u did check on the board by the time you remove the mosfet but u did you just change the without checking the mosfet u been removed coz if u remove a short component u need check by time u remove it but u didn't check the short mosfet but u just replace the other good mosfet
Very hard to understand what you are saying. Maybe try to edit your comment to make it intelligible
Say hallo to my little friend 😂
Good
very nice
👍
Is this laptop dual battery?
Grt job
Nice! 😎
Sorin Sir ***** job
8:54 oh come on, that wire is too thin, for cpu, gpu, ram, heavy load with battery charging.
a proper calibrated wire 😁
This laptop has an internal and an external battery?
Yes
This laptop has two batteries👌
😮kudos
2 batteries??
Looks like it!
It's a thinkpad thing, with 2 separate batteries you can carry one or few of spares and never turn off laptop while you replacing it, Internal act as an UPS and last resource
👍👍👌👌
A replacement board costs £35, so why not replace the board?
This is a nice laptop it's DEAD 🤣
Because you only say nice things about the deceased
Ive noticed Sorin no longer uses "Diode Mode" on his MM to find shorts, he, 100% of the time now, uses resistance mode. What changed ? Just curious. . . . .
Good catch, I noticed that too
He mentioned in a video years ago that diode mode can lead to "false positives." He then proved it with a demonstration and a handrawen diagram to further explain. That's why he uses his power supply (faster diagnosis) to find shorts/overheats alongside the MM,thermal camera, and alcohol tests.
Side note: He used to also use the customers charger to power the board initially, but in one repair, the charger was bad, unbeknownst to him, which led to a bloated repair time. So then he started powering the board with his power supply.
Proper calibrated fuse indeed😂😂😂
It's a capacitor!!!😂
I believe dead fuse prevented you to see short on main power rail, since you cheched before a fuse. When you were after fuse, you saw it.
im sorry, dodgy is dodgy, I wouldnt trust that wire, even if its current rating is similar to the fuses
Why?
@@ddannyable wire isnt made to blow when over current, and is probably thicker than the one in the fuse, and the fuse is, predictably
yeap , but who cares ? you just a saw a blown fuse with first mosfet burned caused by a a shorted capacitor ...so fuse was improper by default
second , you're right, there should be solder a calibrated fuse and more than that fuse must be rapid , wire is a slow fuse !
Whats with all the White Dots...
Let there be 🍕
MAGYAR WINDOWS?????
Egy szerencsés Magyar! 🙂 Honfitárs
tényleg az volt.:DDDDD
Pure doggy fuse. 😂.
Sorin, how can you tell if a MOSFET is channel-P or N without looking up on Google? Are there any indicators?
If the last digit of first number on mosfet is odd then it is PNP and Even number is NPN
In this video the first number is 7121 .so last digit is 1 is odd and PNP mosfet
@@italianofx OK but what about names ending in consonant?
For example: "DA21DT FDPC 5018SG"
Do I take into consideration the last number from the top line (1)?
11:46 Hungarian language Windows.