I was just yelling the entire time... "the other fuse..... The other fuse.... The one on the leeeftt... Thaaatt one... No no.. No. To the left".... But Sorin had a different path.. 😂😂
I ignored that fuse which most likely is good as we have picture and the fuse is on 3.3v power rail, my new multimeter probes are playing, but i could be wrong
I was talking to the screen saying it’s the other H fuse as it went to 4 connected vias on the motherboard connector 🤣. Sorin rocks !! My favorite repair guy on RUclips
I was also screaming...... the fuse with the 'H' on the left you missed😆😉 Could be that Dell switch the 19V with the 3.3V via that H fuse like a relais to the screen ? It's a Dell and a lot of simple things are made difficult, they are good at that
de fapt FZ2 era si ea arsa daca te uiti la minutul 6:36 ai si masurato si era arsa dar tu ai reparat FV1 care si ea era arsa 🤣 chiar ni se intampla tuturor .... o zi faina si video la fel de grozave pe viitor . ajuta pe tot mai multi sa devina chiar electronisti si nu doar schimbatori de placi .
You are correct Sorin, this is a good video. Regardless of missing fixing FZ2 that you found burnt @6:37, the biggest thing to learn is when you do this for a living and time is money, the smart thing is do the fix you know yourself to be quickest and easiest, regardless of 'dodgy', and move on to the next job. A 'bodge' wire job would have seen this fixed in 15 minutes rather than over an hour. Nice one Sorin!
43:23 I was holding my breath for at least backlight to come back. I felt your pain my friend. Time to repair it the best way you can. No reason to spend 2 hours + to come to the same resolution you could have in 20 minutes . :) thanks for sharing !
The H fuse was the 3 dot big power rail for the back light, Sorin just didn't expect to have a 2 blown fuses, (maybe) and forgot to check the big 3 dot powerline,.. The learning lesson is always check All the fuses twice, especially if there is a lot of them in the same small area. Tank you for the lesson Sorin and stay sharp, there is always another way ;)
I have Schematic for this board LA-K371P and I have checked the blown fuses FV1 - Is touchscreen (replaced) FZ2 - is backlight power JEDP1 connector PIN 1-3 is +BL_PWR_SRC (FZ2 fuse) PIN 4 is No Connect PIN 5 is + TS-PWR (FV1 fuse)
Hi, I had to repair some 7420's and it's a truly pain waiting so long while motheboard is resetting BIOS. On the other hand, I have the schematic and FV1 is a fuse for touchscreen power (not important), but FZ2 is a key fuse for Backlight Power.. Sorin, can you check that and may be replace it with a "proper calibrated fuse" hahaha ? I enjoy each video, You're the best !!!
I rechecked the video, and you are correct. I don't think he checked that fuse ever again. Took me 2 mins to find a schematics and boardview. Sometimes being lazy costs you a lot of wasted time.
I really enjoyed the video cause it's long (OF COURSE i don't want you to work SO MUCH sir) but i love the "every single small detail has been recorded"kinda videos Thank You For working hard for the costumers AND FOR SHARING YOUR INCREDIBLE KNOWLEDGE WITH US *ACTUALLY I SHOULD SAY "TEACHING US INSTEAD OF THE WORD SHARING"* HOWEVER THANKS ANYWAYS 😊.
Cred ca e prima data cand te-am auzit injurand in romana Sorin :))))) nistiu ce facea fiecare dintre sigurante insa cum au zis si restul cred ca ambele au fost arse. Am ras, am strigat la monitor, am avut si de invatat din aces video, proper edutainment :)))) Sorin, te ador! Multa sanatate in doresc si numai de bine! Te salut din Timisoara.
i see at the begining that is 2 fuse burn but that don't maters the job is done & i am happy that the laptop works at the end the customer don't need to change motherboard & cost less. Then every one is happy have fun & happy New year to all.
This is one of those occasions where slowing down a little at the initial diagnosis stage may speed the fault finding up. As Sorin said his meter probes could have been playing up which may be why the H fuse seemed bad and may be why there seemed to be no continuity for the main backlight supply through the jdec connector. These are very small components with flux or glue getting in the way. But the fault was the main backlight voltage was missing. Probably because of a logic fault it was switched off via the FET. Sorin eventually bypassed the switched backlight voltage with a direct feed. Given the size of the components and the nature of the fault Sorin did the best fix that was practicable.
You see, you're a pretty good teacher, as many of us saw the mistake and we learned that from you 👍🏻. By the way, what happened to you here is called "confirmation bias" and it was the reason for many plane crashes where skilled pilots made mistakes obvious to observers because of being locked momentarily in a particular path of thinking. Happens to all humans 😄
Im glad im not the only one who nitced he missed a fuse I suspect he fixed the backlight enable fuse and missed the fuse that gives the backlight voltage But its understandable in this line lf work espefiallt when time is money plus trying to video the profess and doing the videos as short as possible and being informative at the same time so easy enoug to make mistakes I as someone who has been doing repairs in electronics fle several years have made my share of mistakes very easy to do when trying tobget kobs done and out the door But regardless i do find these videos super interesting and learning from them as i was more kf old school electrinics the good old CRT TVs and VCRs and audio stuff before i left UK and not really into the more modern circuits with SMD components and chips the size kf a small finger nail but thanks to videos like this has beem great to advance my outdated skills Good work
Dear Sorin. I think laptop manufacturers use fuses instead of wires for a reason. You own a shop, so I think it is not a problem to buy some new fuses and use them to replace blown ones. They cost like nothing. The letter on the fuse tells you its voltage and max amp value. Sorry, I think that replacing fuses with a wire is super dodgy, yet it fixes the issue to make quick money. But I feel bad for the customer that will get a laptop with a fuse replaced with a wire. Replacing the fuse is even faster than soldering the wire. You just need new fuses in stock. Or grab them from spare boards.
Get a wire on it. Get the job done ASAP and move on to the next. Time is money or rest. This is how it works in real life. Happy New Year, Sorin and pupils
Alternatively, “F” stands for “Fast” or “fast-acting fuses” and the “FF” rating stands for ultra-fast fuses such as the one shown here. Ultra-fast fuses operate at higher temperatures and are therefore ideal for providing circuit protection for semiconductor devices
@@balyemez9489 Class H fuses are non-current-limiting fuses with current ratings of up to 600 A and voltage ratings of 250 V or 600 V. As non-current-limiting fuses, Class H fuses only trip after about one and a half cycles, unlike current-limiting fuses which trip much faster (about half a cycle).
@ Class H fuses are non-current-limiting fuses with current ratings of up to 600 A and voltage ratings of 250 V or 600 V. As non-current-limiting fuses, Class H fuses only trip after about one and a half cycles, unlike current-limiting fuses which trip much faster (about half a cycle).
You had 2 blown fuses, 1 was at FZ1 and the other was at FZ2,, you did determine that the both fuses were blown but you forgotten the FZ2 fuse. You ended up bypassing the FZ2 fuse.
Lol you repair the 3.3 power line but not the main power line marked at fuse h even though you checked fuse h to begin with. then caused your self a headache but at the end of the day a fix is a fix
One of my older colleagues was repairing mechanical typewriter. He told me, If I can repair the equipment through chimney and take less time, I will do it. Because you do the repair complicated.!!!
Happy New year 🎉 The whole problem was that you used a "thin wire" instead of a proper calibrated fuse 😂 You started smoking? You stopped the electronic cigarette?
Mmm, looks like the via is internally broken or even shorting to a ground plane. Adding pressure probably connected it temporarily for you when checking with the probes. I would definitely cut the traces from the via on both sides since that looks like the place that caused the fuse to short to ground.
It would be even more interesting if youtube didn't show us the duration of the video from the beginning because that would be even more intriguing. And soldering that wire was a very important part, it is sad it was not recorded...
And could it be that the error message at the end of the video is related to that blown fuse ? Maybe the chipset or EC controller does not give a enable signal because of it ? I'm just putting my thoughts about it, maybe it helps.
sir i want some help regarding that my laptop is facing some issues regarding display which is partial display brightness flickering and when it is off a specific area of display having some light which looks weird and that area only flickers when i increase or decrease the brightness please tell me what should i do ? if u will reply then i will explain this in detail
It should be, if the PWM signal is there. 19v to the screen is always on, if I'm right, it isn't varied. The inverter on the screen adjusts it for what it needs.
19V don't arrive to the connector? Simple you need to put the 19V to the connector in a way or another, I would put the cable at the charging port, because the costumer need to put the charging cable for backlight hahahaha, good job Sorin you are a good teacher
Before you will comment about fuse, read down here. guys, all of you stop screaming about fuse, even i am taking my comment back. Sorrin we love you anyway
Imagine if that was the small MOSFET before the fuse. These exact ones like to die on GPUs 12V PCIE input voltage. If fuse has blown, this FET is likely dead as well.
I was just yelling the entire time... "the other fuse..... The other fuse.... The one on the leeeftt... Thaaatt one... No no.. No. To the left".... But Sorin had a different path.. 😂😂
then?
When he found the blown H fuse and the forgot about it, and then did all that stuff, I had to rage-quit the vid - lol -.
me to he forgot the second fuse he tested was blown
"Age Factor" , i think our Big Teacher needs a Perfect Retirement.
I ignored that fuse which most likely is good as we have picture and the fuse is on 3.3v power rail, my new multimeter probes are playing, but i could be wrong
I was talking to the screen saying it’s the other H fuse as it went to 4 connected vias on the motherboard connector 🤣. Sorin rocks !! My favorite repair guy on RUclips
There were 2 fuses burned. You missed one Sorin.
Exactly
I was also screaming...... the fuse with the 'H' on the left you missed😆😉
Could be that Dell switch the 19V with the 3.3V via that H fuse like a relais to the screen ? It's a Dell and a lot of simple things are made difficult, they are good at that
de fapt FZ2 era si ea arsa daca te uiti la minutul 6:36 ai si masurato si era arsa dar tu ai reparat FV1 care si ea era arsa 🤣 chiar ni se intampla tuturor .... o zi faina si video la fel de grozave pe viitor . ajuta pe tot mai multi sa devina chiar electronisti si nu doar schimbatori de placi .
F is 500mA up to 32V, H is 1A up to 32V
Thanks for the detailed steps in diagnosing backlight problems
2 fuses fixed one and left one it was funny seeing him struggle to finally do a dodgy solution.
You are correct Sorin, this is a good video. Regardless of missing fixing FZ2 that you found burnt @6:37, the biggest thing to learn is when you do this for a living and time is money, the smart thing is do the fix you know yourself to be quickest and easiest, regardless of 'dodgy', and move on to the next job. A 'bodge' wire job would have seen this fixed in 15 minutes rather than over an hour. Nice one Sorin!
You are right. This fuse might be the one for the back light. Overall, nice educational video .
43:23 I was holding my breath for at least backlight to come back. I felt your pain my friend. Time to repair it the best way you can. No reason to spend 2 hours + to come to the same resolution you could have in 20 minutes . :) thanks for sharing !
Si siguranta FZ2 era arsa. Multumesc pentru tot ce faceti, am invatat foarte multe lucruri de la dumneavoastra.Super injuratura in romana 😂
Exact !
The H fuse you forgot @Electronic Repair School
The H fuse was the 3 dot big power rail for the back light, Sorin just didn't expect to have a 2 blown fuses, (maybe) and forgot to check the big 3 dot powerline,.. The learning lesson is always check All the fuses twice, especially if there is a lot of them in the same small area. Tank you for the lesson Sorin and stay sharp, there is always another way ;)
I love how you spend time explaining how easy it is :D
I have Schematic for this board LA-K371P and I have checked the blown fuses
FV1 - Is touchscreen (replaced)
FZ2 - is backlight power
JEDP1 connector
PIN 1-3 is +BL_PWR_SRC (FZ2 fuse)
PIN 4 is No Connect
PIN 5 is + TS-PWR (FV1 fuse)
It’s good Sorin! We got it! Your way is the best and you gave us a beautiful present for the start of the year! THANKS !
Hi, I had to repair some 7420's and it's a truly pain waiting so long while motheboard is resetting BIOS. On the other hand, I have the schematic and FV1 is a fuse for touchscreen power (not important), but FZ2 is a key fuse for Backlight Power.. Sorin, can you check that and may be replace it with a "proper calibrated fuse" hahaha ? I enjoy each video, You're the best !!!
FZ2 is BL Power Source
Started to read comments... It turned out even more interesting than the video... 😁😁😁
in Minute 06:35 you checked Fuse FZ2 is dead, but you did not check FV1 - and only replaced FV1 (i think) :D
Still, one minute later, at 7:30, he says that that's the fuse for 3.3v. A shame he didn't fixed that one too, could have been the issue.
I saw it aswell! FZ2
Good morning, I think the same, FZ2 is burned and not shorted !!!!
There was no continuity between the repaired fuse and the connector pin. So the problem was probably there.
I rechecked the video, and you are correct. I don't think he checked that fuse ever again. Took me 2 mins to find a schematics and boardview. Sometimes being lazy costs you a lot of wasted time.
I really enjoyed the video cause it's long (OF COURSE i don't want you to work SO MUCH sir) but i love the "every single small detail has been recorded"kinda videos
Thank You For working hard for the costumers AND FOR SHARING YOUR INCREDIBLE KNOWLEDGE WITH US *ACTUALLY I SHOULD SAY "TEACHING US INSTEAD OF THE WORD SHARING"* HOWEVER THANKS ANYWAYS 😊.
Cred ca e prima data cand te-am auzit injurand in romana Sorin :))))) nistiu ce facea fiecare dintre sigurante insa cum au zis si restul cred ca ambele au fost arse. Am ras, am strigat la monitor, am avut si de invatat din aces video, proper edutainment :)))) Sorin, te ador! Multa sanatate in doresc si numai de bine! Te salut din Timisoara.
FV1 fuse is for touch screen power. FZ3 fuse is for 3.3V. FZ2 is for Backlight power.
i see at the begining that is 2 fuse burn but that don't maters the job is done & i am happy that the laptop works at the end the customer don't need to change motherboard & cost less. Then every one is happy have fun & happy New year to all.
Hello sorin You missed the FZ2 fuse ...
Dupa ce am scris am vazut ca si alti au observat FZ2. Da se intampla ...doar sa greseli sa facem ca Sorin . Multumim pentru postari.
Hi Lewis
It was great as always, but the fuses on the back of the board, fuse H, were also blown (cut).
What to learn from this video? I'm learning from your videos! Great job.
This is one of those occasions where slowing down a little at the initial diagnosis stage may speed the fault finding up. As Sorin said his meter probes could have been playing up which may be why the H fuse seemed bad and may be why there seemed to be no continuity for the main backlight supply through the jdec connector. These are very small components with flux or glue getting in the way. But the fault was the main backlight voltage was missing. Probably because of a logic fault it was switched off via the FET. Sorin eventually bypassed the switched backlight voltage with a direct feed. Given the size of the components and the nature of the fault Sorin did the best fix that was practicable.
1A 32V fuse should ring a bell. If it is not ringing it is faulty.
he needed to check the 19V after the repaired fuse, but he did not do that, to eliminate the possible mosfet switching possibility.
"Not shure why i'm doing it but yeh, let's do it" :D You are the greatest Sorin!
i think there were 3 fused burned. one is in sorins short term memory ^^
Glad to see you well again.
See you tomorrow 😊
Ps: i also believe it was the 3v3. The one we fixed. The 19 seems to be the other one.
Thanks for the video Master
Fuse H is 32V, 1A
Fuse F is 32V, 500mA
You see, you're a pretty good teacher, as many of us saw the mistake and we learned that from you 👍🏻. By the way, what happened to you here is called "confirmation bias" and it was the reason for many plane crashes where skilled pilots made mistakes obvious to observers because of being locked momentarily in a particular path of thinking. Happens to all humans 😄
"sorry guys is not an easy pizza".
We are sorry for you Sorin, but we do like watching you for 50 minutes, so we are kind of sorry no sorry 😂🙏🏼🙈
Im glad im not the only one who nitced he missed a fuse
I suspect he fixed the backlight enable fuse and missed the fuse that gives the backlight voltage
But its understandable in this line lf work espefiallt when time is money plus trying to video the profess and doing the videos as short as possible and being informative at the same time so easy enoug to make mistakes
I as someone who has been doing repairs in electronics fle several years have made my share of mistakes very easy to do when trying tobget kobs done and out the door
But regardless i do find these videos super interesting and learning from them as i was more kf old school electrinics the good old CRT TVs and VCRs and audio stuff before i left UK and not really into the more modern circuits with SMD components and chips the size kf a small finger nail but thanks to videos like this has beem great to advance my outdated skills
Good work
6:35 "H" fuse blown... Probably your back light😅
lol :D just seen your comment too late - i think too
@christianvogl3629 😄
A lot of us were yelling😂😂😂
Dear Sorin. I think laptop manufacturers use fuses instead of wires for a reason. You own a shop, so I think it is not a problem to buy some new fuses and use them to replace blown ones. They cost like nothing. The letter on the fuse tells you its voltage and max amp value. Sorry, I think that replacing fuses with a wire is super dodgy, yet it fixes the issue to make quick money. But I feel bad for the customer that will get a laptop with a fuse replaced with a wire. Replacing the fuse is even faster than soldering the wire. You just need new fuses in stock. Or grab them from spare boards.
Get a wire on it. Get the job done ASAP and move on to the next. Time is money or rest. This is how it works in real life. Happy New Year, Sorin and pupils
Nice job
Alternatively, “F” stands for “Fast” or “fast-acting fuses” and the “FF” rating stands for ultra-fast fuses such as the one shown here. Ultra-fast fuses operate at higher temperatures and are therefore ideal for providing circuit protection for semiconductor devices
And H ?
And H ?
@@balyemez9489 Class H fuses are non-current-limiting fuses with current ratings of up to 600 A and voltage ratings of 250 V or 600 V. As non-current-limiting fuses, Class H fuses only trip after about one and a half cycles, unlike current-limiting fuses which trip much faster (about half a cycle).
@ Class H fuses are non-current-limiting fuses with current ratings of up to 600 A and voltage ratings of 250 V or 600 V. As non-current-limiting fuses, Class H fuses only trip after about one and a half cycles, unlike current-limiting fuses which trip much faster (about half a cycle).
@@jalalyn many thanks
dear Sorin I think you missed a fuse so it would be better to mark the faulty parts with a red marker so you don't forget them.
Good job mate 👏
You not replaced a blown fuse .. and after that you gone crazy searching the backlight voltage. ( or not ? )
Is that cost ur money?
Yeah.
Just started watching and I see you have new probes and new tweezers 😂😂
The comments!!!! LOL Always entertaining and educational, no matter how dodgy the repair is!
Yea too many scientist in the comment section
nice work
Greetings from Ukraine. Your fault is before the fuse. mossfet that controls the supply of illumination. had such a device with the same malfunction.
You had 2 blown fuses, 1 was at FZ1 and the other was at FZ2,, you did determine that the both fuses were blown but you forgotten the FZ2 fuse. You ended up bypassing the FZ2 fuse.
06:35 FZ2 FZ2 FZ2
Yes, he forgot the dead FZ2 !!!!!!!!!!!!!
Very good my Friend
Lol you repair the 3.3 power line but not the main power line marked at fuse h even though you checked fuse h to begin with. then caused your self a headache but at the end of the day a fix is a fix
One of my older colleagues was repairing mechanical typewriter. He told me, If I can repair the equipment through chimney and take less time, I will do it. Because you do the repair complicated.!!!
One more burn Fuse my friend. I love you
Good job as always!
Sorin beautiful job but i think FZ2 was burned you cheeked it but forgot about it. This what happens when you concentrate to much.
either dell board rejecting enable BL voltage from third party brand lcd panel, or there is invisible broken track. thanks sorin for sharing
Happy New year 🎉
The whole problem was that you used a "thin wire" instead of a proper calibrated fuse 😂
You started smoking? You stopped the electronic cigarette?
Bro nice job
Two blown fuses, bypassed one and forgot the H one, maybe related? Properly calibrated wire was the alternative in the end
I guess this one was the first time we were happy when we still have the picture without back light 😂😂
the issue was those fuse.. but what component did he jump the wire to from power rail?
Sorin are you going to take it apart again and replace the blown fuse you forgot about 😀
Mmm, looks like the via is internally broken or even shorting to a ground plane. Adding pressure probably connected it temporarily for you when checking with the probes. I would definitely cut the traces from the via on both sides since that looks like the place that caused the fuse to short to ground.
That's happened when the first repair guy replace the screen without disconnecting the battery.
the boardview and schematic are available on badcaps, FZ2 is for BL PWR, and FV1 is for TS_PWR (touchscreen). is it the same model?
06:37 - FZ2 - H - FUSE PROBLEM
Hi sorin , why you not check before and after the double diot 😶
Brawo Sorin!!!! Dziękuję za wierzę.
Nice job but just a quation did the liminusity adjastibale??
good job but it was really an easy pizza but you made it very complicated, 2 blown fuses, replaced 1.
Brainless fuse playing with Sorin feelings 😂😂😂
What about checking why the fuse got blown?
It would be even more interesting if youtube didn't show us the duration of the video from the beginning because that would be even more intriguing. And soldering that wire was a very important part, it is sad it was not recorded...
Nice jop mr sorine but i need to know about the green wire you connect to revoltage the connector
how thick calibrated thick for fuse?
Bruh, don't know if you gonna replace that 2nd fuse or not, 25 minutes in, but I'm yelling here into TV to you to replace that fuse! lul
And could it be that the error message at the end of the video is related to that blown fuse ? Maybe the chipset or EC controller does not give a enable signal because of it ? I'm just putting my thoughts about it, maybe it helps.
sir i want some help regarding that my laptop is facing some issues regarding display which is partial display brightness flickering and when it is off a specific area of display having some light which looks weird and that area only flickers when i increase or decrease the brightness
please tell me what should i do ?
if u will reply then i will explain this in detail
Hello good morning what do you think about using PTM7950 in a cellphone
sorin the second fuse H one is burned too
Would the screen brightness still be adjustable?
It should be, if the PWM signal is there. 19v to the screen is always on, if I'm right, it isn't varied. The inverter on the screen adjusts it for what it needs.
19V don't arrive to the connector? Simple you need to put the 19V to the connector in a way or another, I would put the cable at the charging port, because the costumer need to put the charging cable for backlight hahahaha, good job Sorin you are a good teacher
Thankssssss❤
Nice! 😎
You could have just double-checked your fuse check, etc. Anyone can solder, but no one can make it work properly.
Today's lesson, how to complicate an easy pizza.❤
That will be the longest video of changing two fuses. )))
if they were replaced the board what will gone left?😁 repairing is about saving something😄
Don't get bog down with tech headaches just hotwire it 👍😅💷💷
But why did the two fuses blow?
Before you will comment about fuse, read down here. guys, all of you stop screaming about fuse, even i am taking my comment back. Sorrin we love you anyway
2 burn fuses and 1 calibration wire, 😂,
I loved the romanian swear 😂😂😂 , keep up the good work.
You forgot the other fuse that activate the backlight voltage suppose to be 3.2v
All the best in 2025 Sorin.
12:40 "should work"
me : video is 52 minutes "ho noooo..."
Also 18:55 dw we're not doing this hahaha
You only replace one fuse you have two burn fuses on the board sir
the FZ2 is bad too
Imagine if that was the small MOSFET before the fuse. These exact ones like to die on GPUs 12V PCIE input voltage. If fuse has blown, this FET is likely dead as well.