As a machine repair technician, it is very easy to teach someone how a repair should be done, it is much harder to educate someone as to what CAN be done. Sometimes things just need to be made to work, and work NOW. good work sir.
The other day I fixed a Lenovo of my daughter's friend. The charging light was there, but no picture. Watching all of your videos since you opened this channel, I assumed the fault might be a frozen bios. I opened the laptop, unplugged the battery, waited a while, connected the battery again, plugged the charger, pressed the power button and "we have picture." Unfortunately that friend had already bought a new Mac book pro, but she was happy to get all her files back, because she had no backup. And I also felt some kind of accomplishment. Sorin, thanks and please do not think easy fixes or "boring jobs" are not helpful. There are many people who really enjoy your way of getting things done. Thank you again!
Her data was always still available, of course... A six dollar SATA to USB 3 adapter would have let her fetch her files off the naked drive in a few minutes. But it is kinda cool to now have an extra laptop. It's just sad that she went to the dark side... ;-]
@@robertcartier5088 Yes, I could have done that, but this young lady wouldn't even know how to open her laptop to retrieve the drive. What I've heard she was in panic to hand in a report, purchased the Mac and started all over again. At 3 am she could finally finish. Unfortunately, I got her Lenovo a few days later. "The dark side" is a good one!
God bless you man ! i have like 60+ defected laptops and they siting for 2,3 years like graveyard after I become addicted and started watching your videos every day I made some of them work! didn't even tested half I'm going rly slowly and learning from you step by steam ! we are all blessed we have you on youtube
I started at 20yr old to to have an AS Degree in electronics and not I'm 74 and still learning to ID the SMD components by watching you name them as you test them. I still have a steady hand to do the micro solder with your help of showing the componants and how you test them. Thank you.
Mr Sorin your Dodgy way is better than the Schematic way!Less time,faster and the job is done!I visit your channel every day for new videos like this!Thank you again for your time and knowledge you spent with us!
A pleasure to se someone like Sorin go through the logic to find where the problem was, OK he didn't replace the MOSFET but like he says, its just a switch. and he got the laptop working without it. well done
I completely understand the decision here especially without schematic. Schematics should be free and obtainable for everything to save the environment.
@@fikrinoh1135 The main reason no schematics are available today is because no manufacturer actually wants the customer or repair shops to fix their products. If it's broken throw it out and buy a new one. A few decades ago this was different. That might change in the future if governments around the world put laws in place that forces manufacturers to design electronics with repairability in mind. Freely available schematics, cheap spare parts, no more glued down internal batteries in smartphones etc. It would be good for the customers wallet and we would also produce less e-waste that pollutes our planet.
@@troemich Totally agree, except the part where it would be cheaper for the customer... To make the devices repairable, they would necessarily have to be built to higher standards to, a) have longer lasting parts, and b) stand up to the physical abuse of being opened, repaired, and closed over and over again. That kind of quality construction costs money... There has to be a happy medium in there somewhere. ;-)
@@robertcartier5088 You misunderstood my post. I didn't mean that every device would need to be a quality device and cost a few thousand bucks. Considering that most Notebooks today even the cheap ones can be opened quiet easy, I mean you see Sorin do it often, repairing them wouldn't be so hard. If the manufacturer has to sell spare parts for a fair price and needs to release schematics to the public, devices could be fixed easier and faster. Why buy a new mainboard or even a whole new laptop if some repair shop could fix your broken board with schematics available. Of course not every fault is fixable but a lot more than with no schematics. Fixing stuff with schematics in hand would be cheaper for the customer as the fault could be diagnosed and fixed a lot faster. Mainboards and special touchscreens for laptops sometimes are way more expensive than what the whole laptop cost a few years ago. Even simple parts like the plastic housing are sold way overpriced or not at all. Not worth repairing. If spare parts had to be sold at a fair price and for at least five years, fixing them would be cheaper for the customer. Of course laptop manufacturers would need to rethink their strategy of releasing a gazillion different laptop models each year. A few models per manufacturer and new models when better tech comes around. Smartphones used screws and plastic clips not even a decade ago. Then they started using glass and aluminium as material and things got glued down instead of screwed down. Nowadays you can't even swap out a dead or dying battery from a smartphone without fighting glue. Unless you buy a Fairphone.
Hey Sorin, do you know the name of that clear plastic film or tape covering the board at 3:38? I know there's also black one but where can i find these things for sale? Thanks
@@electronicsrepairschool I really appreciate your work Sorin. You are amazing and you share with us your passion. I never touched a solder iron since I discovered your channel. 3 months later I'm looking for dead laptop on ebay and others, and I'm able to fix them... That's incredible and you make that possible... Again, thank you sir!
Sorin explains and talks in a way it's very easy to understand and follow and learning. And he has some good innovation. It's really great and I think everyone is super glad you taking your time to do this.
Hi Sorin good to sèé you back at work 👋🏼 ASUS X541S-XX154T with No Power that had a Short on the Main Power Rail which was due to a bad large Cap on one of other Power Rails and once the Cap was removed the Short had gone but still No Power coming through the first 19.20v Charger Port MOSFET with 0.00v on the Gate. The next thing was to check the Battery which was found to be completely dead with 0.00v Output so each of the 3 Cell Wires were removed from the Battery PCB to Charge each Cell up individually to reach their maximum Charge Levels of 4.2v and once Charged reconnected back up to the Battery PCB but still there was No Power on the Battery Output Connector so a Replacement Battery was ordered in, once the Replacement Battery had arrived it was connected to the machine which would Power Up the Main Board but still No 19.20v Charger Port Power coming through the MOSFET with 0.00v at the Gate with or without the presents of the MOSFET which still wouldn’t Charge the Battery neither would Windows sèé the attached Battery once booted up into the OS also Jumping the Charger Port MOSFET would supply Power to the Main Board but it still couldn’t Charge the Battery. My question now is could all of the above be down to a Bad somewhat Damaged “ENE KB902FQ C Power Management IC Chip” which this particular board has???? Any Help or Suggestions would be Muchly Appreciated.
Sorin, It would be nice if you summarize the things at the end! Sometimes its very hard to follow your train of touts! After tinkering for half an hour you suddenly decided to bypass the mosfet. I didn't learn much from this example. I don't mean to criticize you as i very much appreciate your willingness to help others for free and admire your skills! Thank you!
watch rest of his videos and older videos and you will know exactly why he decided to short it , simply cause it is a long story to be digging deep to find the cause not worth it when the solution is simple and easy . to learn much you have to start from the beginning and watch all his videos , don't skip and you will find the answer yourself . Good luck
January is boring because every one is playing with there new laptops and other toys.. by the end of February or march they have broken them and now want them fixed.. or the new has worn off and they realize they like here old stuff better.. Thanks my friend.. this was good.
haha, suuuper, esti roman! In episodul acesta mi-am dat seama cand te-ai incurcat si ai zis ca even february will be "la fel" :)) Faci o super treaba Sorin!
daaa e roman :) are clipuri in care se aude ca vorbeste romana. i-am spus a faca cateva clipuri si in romana, dar nu mi-a raspuns pana acum :( pacat ca sta in Anglia
Hi Sorin you may think that the jobs you do are boring but to a person just getting into helping to fixing computers your videos are a great help even if you do not find and fix them in the most conventional way . I have a Question when you say fix a broken truck to a chip with a wire why do you use such a small wire does it not increase the resistance to the chip making it extra hot at that point some times the the width of the soldering wire you use looks more the right size finally what is the size and make you use many thanks a avid viewer
Had this same laptop generation. Laptop will only turn on if plugged on the AC outlet, will not charge (stuck at 88%) and turns off when you pull charger out from the wall . I opened it and checked its internal battery and it's fine. Plugged a replacement battery and same issue. Turns out that you have to reset the battery by turning it off, unplug from wall, press and hold to power button for less than a minute, plug it and turn it on and uninstall the ACPI something from the device manager. Rebooted and system reinstalled its drivers and issue was resolved.
The charging ic is a very smart ic it talks to the battery and to the EC (super io) if the charge pump to the gate is shorted to the 19v or ground rail I will not charge the battery I had an hp laptop that did not charge the battery even if you shorted the first mosfet S to D , The laptop would turn on but no charging , that hp laptop had a cap from dc in to the gate that was leaking current and drawing the charge pump down. on this laptop the fault is the 2nd mosfet G is shorted , those mosfet are n channel and require a higher voltage to switch on about 23V , I would test the mosfets :)
I sat and stared at a bq277xx series datasheet for hours trying to fix an asus with the exact problem sorins had in the video. I never thought to check for a shorted charge pump. Ugh. Thanks Anon.
at 5:00 you verified if the voltage and it's 19.5V. If mine shows 0 on that side(as in the video) but if i measure from the behind it gives 19.5V does it mean that's ok ? Does the current need to travel on the back of the board also?
Thanks!! You have helped me a lot, I had the same fault that you show in an ASUS TP300L. The same Mossfett after the connector, which has no trigger current. I've bypassed it and at least the laptop turns on. Let's see if someone can help me, novice doubts come: - Can the laptop work without that mossfet? - How can I continue looking for the fault, any suggestion of a component that usually fails? All the best!
Ok i have read through the comments but dont see anyone ask the question. There is 19v input to mosfet and about 3v on the gate which should be enough to make it switch. If the output is not 19v then the mosfet IS faulty right? Why do you say it is fine?
the mosfet is switching the same voltage on gate . if the gate have 19V it will switch the 19V input to 19V output . so mosfet is fine . it can be faulty if no voltage at all on gate with respect to making sure no short to ground . so if all good and no short but mosfet has no voltage at all on gate or near to zero you can ay at the point it is faulty , you can replace it or you can short it which is simple and easier and it will do the same job
Its good to see Sorin back and on top Mosfet-bridging form! Fair play for the diagnostic attempt though! Someone should design a T-Shirt with a bridged Mosfet :-)
In the past, with a dead laptop, I have shorted out the mosfet myself and everything worked fine. I now have two of the same laptops, (Asus). Both work fine with the charger plugged in but die instantly the charger is removed. I have tested the battery pack with a 12 volt car headlight (actually 4 bulbs in parallel), and the batteries are good. So it's not the batteries, it could be the BMS within the battery pack, but I don't know. I have ordered a replacement battery pack just in case. Any chance of a video on this topic? Please....
Hi! I've found your video extremely useful! I have an x540N with the same board. It can be powered up via ac adapter, but it doesn't charge battery. Also, the battery has around 60% charged (I can see the measurement on the BIOS), but the pc doesn't turn on with battery only. I have around 12v on battery (measured with a tester on + and - on batteries). What could I check? Thanks a lot!
thanks for being back on youtube. I follow you very carefully ... could you sometimes make videos of TV repairs? p.s: in this video it could be some transistor that drives some "secondary" MOSFET that goes to drive the two main MOS ... maybe. Thank you, Angelo from Italy.
@@JamRoleStudio for mine they said it's the power that is not delivered correctly, but well it's kinda my fault, I did open it without thinking of static electricity , and now something broke (at least it's not the cpu)
Hello 👋. I have an Asus laptop, model k555l with x555ld REV .3.6 main board. I had connected my laptop's cooling pad using a 9-volt and half-ampere adapter, but I wasn't paying attention and the cooling pad was also simultaneously connected to the laptop via the USB port. Now my laptop turns on, but the laptop screen shows no sign of being on. In your opinion, which part has been damaged by this simultaneous connection of the cooling pad adapter and the connection of the cooling pad via USB to the laptop?
hi, how do you find faults without patterns? Congratulations. I'm starting to fix something again. I still have instruments including a fluke 87 III multimeteo. Is it okay with you for measurements? Thank you
Hi just wanted to say not everyone watches for interesting hard jobs I mean yes there good but it’s good to see things Evan simple things from you’re prospective keep up the good work 👍🏼
hello sir. from philippines.. what is the effect of removing that mosfet to the laptop? is there any side effect? why is that u can just change a mosfet instead of soldering? you know it bother me this question and im looking forward for your answer. thank you sir
Just saw your question. Since no one has answered, I'll do my best. As he said, the MOSFET in this case was acting as a switch for protection. If something goes wrong with the main board, that MOSFET won't switch on because the other circuit driving it senses that there is a fault and stops the 19 volts from damaging any other parts that are under too much load during the fault condition. What he did was to put 19 volts on the output side of the MOSFET and he could see that the laptop was trying to start up. That means there is no fault on the rest of the board. The sensing circuit is faulty and only *thinks* there is a problem. He jumpered out the MOSFET so the 19 volts was on all the time which is like the sensing circuit saying all ok all the time. The laptop ran fine because there was no other fault. If there is a fault in future, such as a short circuit in a component, that component or part of the circuit board etc may be damaged since the protection can't work. It still might be repairable even after that but maybe not. Still, it is working fine for a small cost to the customer now. I would definitely do this repair too since sense circuits are complex and often tricky. I would tell the customer though and they can decide - have it now, cheap fix or pay big money for a new board or complex repair. Unless it is very new, customer goes cheap :)
How many layers have that pcb ? Maybe 6 -7 layers and the track of the second resistor is somewhere between external principal layers.. it takes about several hours of search to find it..
Sorin. Did you come to any conclusion about your previous job on the battery issue. Some were saying a mosfet issue. . Others battery circuitry issue. Do you have further comment on that one.
Hi sir. I have an Asus x553m It just went of, can't charge or turn on. Wen I plug it to charge and turn it on it just shows a green light (charge light)on led and goes off. Wat could be the problem with this one. I tried removing battery and waiting for one minute and press power button, but still couldn't work. Please help.
Hi Sorin! Very nice repair! An idea: wouldn't it be better to put a diode instead of the wire bridge, exactly in the serial mode as the mosfet you removed, pointing the Cathode to the next mosfet, so one can be sure that no power goes backwards, maybe foling the super I/O chip? ... well mine it' just a thought just in case...
@@Customer22374rt I meant "In the place* of the wire bridge sorin often puts to repair these faults, to put the Anode diode where the 19V gets in fro m the charging Port, and the Cathode to the second mosfet. This to prevent the Battery voltage to go backwards to Charging Port, connector and/or other components that could be there (also, maybe, the super I/O chip in the cases where it checks also that port) in the cases when the charging port is connected to the external power supply, but this is not connected to the Mains AC Voltage. Hope it's clearer now.
@@mariodistefano2973 only thing i don't understand is this sentence (( in the cases when the charging port is connected to the external power supply, but this is not connected to the Mains AC Voltage ))
@@Customer22374rt Ok. I'll try to explain it better. Sorin did a wire bridge, "replacing" the first mosfet. So, when the computer is working on it's own battery, you have the +12V battery voltage, (instead of +19V) on that wire bridge. Since the first Mosfet has been replaced by the wire, this voltage also possibly go backwards to the charging port input (possibly, because it depends on how the schematic actually is). So if you accidentally have the charger already plugged in the charging port, whle the charger itself is not plugged into the mains voltage, you have (possibly: also here it depends on the actual schematic) this +12V go into the charger... This is why I was thinking to put a diode instead of the wire. To prevent this "accidental & unwanted" current flow path. Simply that.
@@mariodistefano2973 not being rude but what are you saying will never happen cuz DC voltage and battery voltage have difference bath , they are separate circuits , both are feeded from the main mosfet which he bridged it , not just a theory but i tried it myself , so diode or wire bridge doesn't really matter in this case . thank you
So the MOFSET is proportional? The gate had 3.3V so shouldn't the MOFSET just pass the 19.5V (or not) but it was passing just 3V if it's a just a switch how was it allowing a reduced voltage to pass? (unless switching really quick :)
Hii I have exactly the same model of ASUS X540N that I bought a month ago Lastweek it reached 0% i tried charging it but it dd not show life. What could be the problem with it Your response wil be highly appriciated
4 роки тому
If the main power rail goes directly into N-MOSFET, then what is switching that MOSFET on? If MOSFET is switched off, then there is no power if the battery is also not installed. So what is controlling the gate of MOSFET then?
This laptop was $450 on amazon, but it's more on the level of a lenovo 100s, a baytrail based ultrabook that retailed for $199 in 2017. Maybe the pentium is faster but we're talking bottom tier components here, it's all basically the same. It's just crazy that 3 inches more display allows them to jack the price up that much.
Salut, Sorin :) uite.. am o intrebare pt acest laptop :D :) am vazut acum ca la sfarsit dupa ce ai terminat treaba si ai conectat incarcatorul... laptopul a pornit.. asta fara ca sa mai faci.. power on din buton de la tastatura.. ?? pt ca la alte laptop-uri treaba asta nu se intampla :) ??
As a machine repair technician, it is very easy to teach someone how a repair should be done, it is much harder to educate someone as to what CAN be done. Sometimes things just need to be made to work, and work NOW. good work sir.
The other day I fixed a Lenovo of my daughter's friend. The charging light was there, but no picture. Watching all of your videos since you opened this channel, I assumed the fault might be a frozen bios. I opened the laptop, unplugged the battery, waited a while, connected the battery again, plugged the charger, pressed the power button and "we have picture." Unfortunately that friend had already bought a new Mac book pro, but she was happy to get all her files back, because she had no backup. And I also felt some kind of accomplishment.
Sorin, thanks and please do not think easy fixes or "boring jobs" are not helpful. There are many people who really enjoy your way of getting things done. Thank you again!
Her data was always still available, of course... A six dollar SATA to USB 3 adapter would have let her fetch her files off the naked drive in a few minutes. But it is kinda cool to now have an extra laptop. It's just sad that she went to the dark side... ;-]
@@robertcartier5088 Yes, I could have done that, but this young lady wouldn't even know how to open her laptop to retrieve the drive. What I've heard she was in panic to hand in a report, purchased the Mac and started all over again. At 3 am she could finally finish. Unfortunately, I got her Lenovo a few days later. "The dark side" is a good one!
God bless you man ! i have like 60+ defected laptops and they siting for 2,3 years like graveyard after I become addicted and started watching your videos every day I made some of them work! didn't even tested half I'm going rly slowly and learning from you step by steam ! we are all blessed we have you on youtube
Hi...sir.
I learned a lot of things from you.
May God always with you.
I started at 20yr old to to have an AS Degree in electronics and not I'm 74 and still learning to ID the SMD components by watching you name them as you test them. I still have a steady hand to do the micro solder with your help of showing the componants and how you test them. Thank you.
Mr Sorin your Dodgy way is better than the Schematic way!Less time,faster and the job is done!I visit your channel every day for new videos like this!Thank you again for your time and knowledge you spent with us!
A pleasure to se someone like Sorin go through the logic to find where the problem was, OK he didn't replace the MOSFET but like he says, its just a switch. and he got the laptop working without it. well done
I completely understand the decision here especially without schematic. Schematics should be free and obtainable for everything to save the environment.
The reason why schematic is not available to be obtained is because to avoid counterfeiting.
@@fikrinoh1135 The main reason no schematics are available today is because no manufacturer actually wants the customer or repair shops to fix their products. If it's broken throw it out and buy a new one. A few decades ago this was different. That might change in the future if governments around the world put laws in place that forces manufacturers to design electronics with repairability in mind. Freely available schematics, cheap spare parts, no more glued down internal batteries in smartphones etc. It would be good for the customers wallet and we would also produce less e-waste that pollutes our planet.
@@troemich yup, totally agree!
@@troemich Totally agree, except the part where it would be cheaper for the customer... To make the devices repairable, they would necessarily have to be built to higher standards to, a) have longer lasting parts, and b) stand up to the physical abuse of being opened, repaired, and closed over and over again. That kind of quality construction costs money... There has to be a happy medium in there somewhere. ;-)
@@robertcartier5088 You misunderstood my post. I didn't mean that every device would need to be a quality device and cost a few thousand bucks. Considering that most Notebooks today even the cheap ones can be opened quiet easy, I mean you see Sorin do it often, repairing them wouldn't be so hard. If the manufacturer has to sell spare parts for a fair price and needs to release schematics to the public, devices could be fixed easier and faster. Why buy a new mainboard or even a whole new laptop if some repair shop could fix your broken board with schematics available. Of course not every fault is fixable but a lot more than with no schematics.
Fixing stuff with schematics in hand would be cheaper for the customer as the fault could be diagnosed and fixed a lot faster.
Mainboards and special touchscreens for laptops sometimes are way more expensive than what the whole laptop cost a few years ago. Even simple parts like the plastic housing are sold way overpriced or not at all. Not worth repairing. If spare parts had to be sold at a fair price and for at least five years, fixing them would be cheaper for the customer. Of course laptop manufacturers would need to rethink their strategy of releasing a gazillion different laptop models each year. A few models per manufacturer and new models when better tech comes around.
Smartphones used screws and plastic clips not even a decade ago. Then they started using glass and aluminium as material and things got glued down instead of screwed down. Nowadays you can't even swap out a dead or dying battery from a smartphone without fighting glue. Unless you buy a Fairphone.
You are the reason to make me dive to electronics.
I learn a lot from you.Thank you.
I have seen your comments in almost all sorins videos
So glad to see another video from you, does not matter how you fix the things as long as they work normally in the end. Thank you for your work
Nice to have you back Sorin! I joined your Discord server and amazing how so many people are willing help beginners like me there! Cheers!
Thanks God, the Master is back !!
I'm glad you are back Sorin, I have missed you
Hey Sorin, do you know the name of that clear plastic film or tape covering the board at 3:38? I know there's also black one but where can i find these things for sale? Thanks
Finally Sorin is back. Need daily videos... Good to see you
Thank you
@@electronicsrepairschool I really appreciate your work Sorin. You are amazing and you share with us your passion. I never touched a solder iron since I discovered your channel. 3 months later I'm looking for dead laptop on ebay and others, and I'm able to fix them... That's incredible and you make that possible... Again, thank you sir!
Sorin explains and talks in a way it's very easy to understand and follow and learning. And he has some good innovation. It's really great and I think everyone is super glad you taking your time to do this.
Hi Sorin good to sèé you back at work 👋🏼
ASUS X541S-XX154T with No Power that had a Short on the Main Power Rail which was due to a bad large Cap on one of other Power Rails and once the Cap was removed the Short had gone but still No Power coming through the first 19.20v Charger Port MOSFET with 0.00v on the Gate.
The next thing was to check the Battery which was found to be completely dead with 0.00v Output so each of the 3 Cell Wires were removed from the Battery PCB to Charge each Cell up individually to reach their maximum Charge Levels of 4.2v and once Charged reconnected back up to the Battery PCB but still there was No Power on the Battery Output Connector so a Replacement Battery was ordered in, once the Replacement Battery had arrived it was connected to the machine which would Power Up the Main Board but still No 19.20v Charger Port Power coming through the MOSFET with 0.00v at the Gate with or without the presents of the MOSFET which still wouldn’t Charge the Battery neither would Windows sèé the attached Battery once booted up into the OS also Jumping the Charger Port MOSFET would supply Power to the Main Board but it still couldn’t Charge the Battery.
My question now is could all of the above be down to a Bad somewhat Damaged “ENE KB902FQ C Power Management IC Chip” which this particular board has????
Any Help or Suggestions would be Muchly Appreciated.
It’s always a pleasure to watch your videos. Really inspiring and helpfull to diagnose without schematics. Great job !
I am so glad to have found these video's. This is worth gold.
Thank you Sir ,did the same to Asus X541SA it worked for me after I watched this video, Thank you a million ❤.Stay blessed
Sorin, It would be nice if you summarize the things at the end! Sometimes its very hard to follow your train of touts! After tinkering for half an hour you suddenly decided to bypass the mosfet. I didn't learn much from this example. I don't mean to criticize you as i very much appreciate your willingness to help others for free and admire your skills! Thank you!
watch rest of his videos and older videos and you will know exactly why he decided to short it , simply cause it is a long story to be digging deep to find the cause not worth it when the solution is simple and easy . to learn much you have to start from the beginning and watch all his videos , don't skip and you will find the answer yourself . Good luck
@@Customer22374rt Thanks for reply! I don't skip but he does becouse it's natural for him!
Yess he is back.
Thanks again it’s a nice try to find the problem without being doggy. You are great make it work almost every time 100%
Sorin is back!! ✌
Mi-ar face multa placere.. Sorin, poate intr-o zi.. sa putem sta de vb.. sunt sigur caa.. m-ai putea lamuri cu cateva lucruri despre problema :)
January is boring because every one is playing with there new laptops and other toys.. by the end of February or march they have broken them and now want them fixed.. or the new has worn off and they realize they like here old stuff better.. Thanks my friend.. this was good.
haha, suuuper, esti roman! In episodul acesta mi-am dat seama cand te-ai incurcat si ai zis ca even february will be "la fel" :)) Faci o super treaba Sorin!
daaa e roman :) are clipuri in care se aude ca vorbeste romana.
i-am spus a faca cateva clipuri si in romana, dar nu mi-a raspuns pana acum :( pacat ca sta in Anglia
Asa mi-am dat si eu seama ca e roman cnd l-am auzit vorbind in cateva randuri.
Hi Sorin you may think that the jobs you do are boring but to a person just getting into helping to fixing computers your videos are a great help even if you do not find and fix them in the most conventional way . I have a Question when you say fix a broken truck to a chip with a wire why do you use such a small wire does it not increase the resistance to the chip making it extra hot at that point some times the the width of the soldering wire you use looks more the right size finally what is the size and make you use many thanks a avid viewer
Thank you so much!! I repaired my computer with this video
I learn something new everytime I watch your video. Thank you.
Excellent repair and hints for fixing laptops easily (at least some faults)! Finding that mosfets driving signal back could be pain in the a... 👍
Had this same laptop generation. Laptop will only turn on if plugged on the AC outlet, will not charge (stuck at 88%) and turns off when you pull charger out from the wall . I opened it and checked its internal battery and it's fine. Plugged a replacement battery and same issue. Turns out that you have to reset the battery by turning it off, unplug from wall, press and hold to power button for less than a minute, plug it and turn it on and uninstall the ACPI something from the device manager. Rebooted and system reinstalled its drivers and issue was resolved.
more updates please! we love you sorin! :D
The charging ic is a very smart ic it talks to the battery and to the EC (super io) if the charge pump to the gate is shorted to the 19v or ground rail I will not charge the battery I had an hp laptop that did not charge the battery even if you shorted the first mosfet S to D , The laptop would turn on but no charging , that hp laptop had a cap from dc in to the gate that was leaking current and drawing the charge pump down. on this laptop the fault is the 2nd mosfet G is shorted , those mosfet are n channel and require a higher voltage to switch on about 23V , I would test the mosfets :)
What about the 1st mosfet, the gate only has 3.1v. What's the connection to the 2nd mosfet?
@@pilotboy2612 If it was the first mosfet there would be 19v on gate the first and second mosfet gates are joined
I sat and stared at a bq277xx series datasheet for hours trying to fix an asus with the exact problem sorins had in the video. I never thought to check for a shorted charge pump. Ugh. Thanks Anon.
@@sagebrushrepair I had two boards with this problem , Spent hours solving this problem. Glad it helped some one :)
I'm glad you are back Sorin
at 5:00 you verified if the voltage and it's 19.5V. If mine shows 0 on that side(as in the video) but if i measure from the behind it gives 19.5V does it mean that's ok ? Does the current need to travel on the back of the board also?
Thanks!! You have helped me a lot, I had the same fault that you show in an ASUS TP300L. The same Mossfett after the connector, which has no trigger current.
I've bypassed it and at least the laptop turns on.
Let's see if someone can help me, novice doubts come:
- Can the laptop work without that mossfet?
- How can I continue looking for the fault, any suggestion of a component that usually fails?
All the best!
Ok i have read through the comments but dont see anyone ask the question. There is 19v input to mosfet and about 3v on the gate which should be enough to make it switch. If the output is not 19v then the mosfet IS faulty right? Why do you say it is fine?
the mosfet is switching the same voltage on gate . if the gate have 19V it will switch the 19V input to 19V output . so mosfet is fine . it can be faulty if no voltage at all on gate with respect to making sure no short to ground . so if all good and no short but mosfet has no voltage at all on gate or near to zero you can ay at the point it is faulty , you can replace it or you can short it which is simple and easier and it will do the same job
Great to see you back 👍
Why don´t you checked the second mosfet? It´s a common fault, this P0903BEA mosfet goes to short...
I checked your Videos, great but it would be better in English...
Happy to see you again Sorin
Happy new year Sorin and welcome back! So, is the mosfet faulty or the driver that drives that mosfet?
I have learnt so much from you Sir, thank you.
Make it easy so that we can earn more. Newbie here trying to learn, watching all your videos.
good morning
a great master you are , i learn many things from your videos
thank you so much mister sorin .
thanks for all your work, I think the real fault is on the charger circuit, this circuit is meant to open those mosfets. Good luck to everyone
Not boring to me.. Thanks for the video.
Its good to see Sorin back and on top Mosfet-bridging form! Fair play for the diagnostic attempt though! Someone should design a T-Shirt with a bridged Mosfet :-)
That was a nice comeback ;) .
The video has been saved in the milestones folder.
Thank you Sorin for a nice video
I bought same laptop and it has a same fault lol fixed thanks to sorin :D
I think first mosfet's G - S was shorted. they have same voltage and Gate shouldn't have 3V.
Are you alive!? Good to get you back
what are the differences if you short the mosfet and if trying to figure out what is faulty ? anyway thanks for the video.
Its time , the difference is just time. Because at the end HE will fix anything.
In the past, with a dead laptop, I have shorted out the mosfet myself and everything worked fine. I now have two of the same laptops, (Asus). Both work fine with the charger plugged in but die instantly the charger is removed. I have tested the battery pack with a 12 volt car headlight (actually 4 bulbs in parallel), and the batteries are good. So it's not the batteries, it could be the BMS within the battery pack, but I don't know. I have ordered a replacement battery pack just in case.
Any chance of a video on this topic? Please....
Very nice Mr. Sorin l Iearned a lot from your techniques -Filipino Technician
Sorin, thanks for sharing your knowledge for free.
so you short the 1st mosfet,from source to the drain and to the gate?
Will be “ la fel” 😂. Salutare din romania 👍🏻 mult succes in ceea ce faceti
you are génious !
I have the same problem but can't work like you :( you are a PRO
how to bridge MOSFET? I cant clearly see in the video sir
Sooo awesome. Welcome back sorin.
Sorin pokes the warranty sticker immediately. :))
Hi! I've found your video extremely useful! I have an x540N with the same board. It can be powered up via ac adapter, but it doesn't charge battery. Also, the battery has around 60% charged (I can see the measurement on the BIOS), but the pc doesn't turn on with battery only. I have around 12v on battery (measured with a tester on + and - on batteries). What could I check? Thanks a lot!
thanks for being back on youtube. I follow you very carefully ... could you sometimes make videos of TV repairs?
p.s: in this video it could be some transistor that drives some "secondary" MOSFET that goes to drive the two main MOS ... maybe.
Thank you, Angelo from Italy.
So do you recommend me doing that or going to a repairshop
well the repair shop i went said they won't do that. Maybe with luck i can find one like that.
@@kingnotora i have 2 laptop with the same problem. But it turns out that it qas only the charger for 1
@@JamRoleStudio for mine they said it's the power that is not delivered correctly, but well it's kinda my fault, I did open it without thinking of static electricity , and now something broke (at least it's not the cpu)
This is very interesting to watch. I have an Asus K50 AF laptop that has the same symptoms.👍
That's one durable logitech mouse you've got Sorin.
you are a big help .i learn so much from your videos.thank you sir
Hello 👋. I have an Asus laptop, model k555l with x555ld REV .3.6 main board. I had connected my laptop's cooling pad using a 9-volt and half-ampere adapter, but I wasn't paying attention and the cooling pad was also simultaneously connected to the laptop via the USB port. Now my laptop turns on, but the laptop screen shows no sign of being on. In your opinion, which part has been damaged by this simultaneous connection of the cooling pad adapter and the connection of the cooling pad via USB to the laptop?
Thanks Sorin knowledge & entertainment . Bargain . : - )
Happy New Year Sorin!
Thank you, same to you!
The calibrated fuse comes to the rescue once again.
hi, how do you find faults without patterns? Congratulations. I'm starting to fix something again. I still have instruments including a fluke 87 III multimeteo. Is it okay with you for measurements? Thank you
Hi just wanted to say not everyone watches for interesting hard jobs I mean yes there good but it’s good to see things Evan simple things from you’re prospective keep up the good work 👍🏼
hello sir. from philippines.. what is the effect of removing that mosfet to the laptop? is there any side effect? why is that u can just change a mosfet instead of soldering? you know it bother me this question and im looking forward for your answer. thank you sir
Just saw your question. Since no one has answered, I'll do my best. As he said, the MOSFET in this case was acting as a switch for protection. If something goes wrong with the main board, that MOSFET won't switch on because the other circuit driving it senses that there is a fault and stops the 19 volts from damaging any other parts that are under too much load during the fault condition. What he did was to put 19 volts on the output side of the MOSFET and he could see that the laptop was trying to start up. That means there is no fault on the rest of the board. The sensing circuit is faulty and only *thinks* there is a problem. He jumpered out the MOSFET so the 19 volts was on all the time which is like the sensing circuit saying all ok all the time. The laptop ran fine because there was no other fault. If there is a fault in future, such as a short circuit in a component, that component or part of the circuit board etc may be damaged since the protection can't work. It still might be repairable even after that but maybe not. Still, it is working fine for a small cost to the customer now. I would definitely do this repair too since sense circuits are complex and often tricky. I would tell the customer though and they can decide - have it now, cheap fix or pay big money for a new board or complex repair. Unless it is very new, customer goes cheap :)
Hi, answer is this laptop will not charge battery and will turn on itself.
How many layers have that pcb ? Maybe 6 -7 layers and the track of the second resistor is somewhere between external principal layers.. it takes about several hours of search to find it..
Great Job Keep it UP !!!! Thanks master sorin keep uploading video i’m still learning 😁👍🏻
Sorin. Did you come to any conclusion about your previous job on the battery issue. Some were saying a mosfet issue. . Others battery circuitry issue. Do you have further comment on that one.
Hi sir.
I have an Asus x553m It just went of, can't charge or turn on. Wen I plug it to charge and turn it on it just shows a green light (charge light)on led and goes off. Wat could be the problem with this one. I tried removing battery and waiting for one minute and press power button, but still couldn't work.
Please help.
flash the bios
@@Customer22374rt how do I do it.
And where is it located exactly?
@@simategeoffrey.s8923 google it sir
Do you have a link or name of the charger for it?
Hi Sorin! Very nice repair! An idea: wouldn't it be better to put a diode instead of the wire bridge, exactly in the serial mode as the mosfet you removed, pointing the Cathode to the next mosfet, so one can be sure that no power goes backwards, maybe foling the super I/O chip? ... well mine it' just a thought just in case...
so in the mosfet input will be the cathode and the output will be the anode ?
@@Customer22374rt I meant "In the place* of the wire bridge sorin often puts to repair these faults, to put the Anode diode where the 19V gets in fro m the charging Port, and the Cathode to the second mosfet. This to prevent the Battery voltage to go backwards to Charging Port, connector and/or other components that could be there (also, maybe, the super I/O chip in the cases where it checks also that port) in the cases when the charging port is connected to the external power supply, but this is not connected to the Mains AC Voltage. Hope it's clearer now.
@@mariodistefano2973 only thing i don't understand is this sentence (( in the cases when the charging port is connected to the external power supply, but this is not connected to the Mains AC Voltage ))
@@Customer22374rt Ok. I'll try to explain it better. Sorin did a wire bridge, "replacing" the first mosfet. So, when the computer is working on it's own battery, you have the +12V battery voltage, (instead of +19V) on that wire bridge. Since the first Mosfet has been replaced by the wire, this voltage also possibly go backwards to the charging port input (possibly, because it depends on how the schematic actually is).
So if you accidentally have the charger already plugged in the charging port, whle the charger itself is not plugged into the mains voltage, you have (possibly: also here it depends on the actual schematic) this +12V go into the charger... This is why I was thinking to put a diode instead of the wire. To prevent this "accidental & unwanted" current flow path. Simply that.
@@mariodistefano2973 not being rude but what are you saying will never happen cuz DC voltage and battery voltage have difference bath , they are separate circuits , both are feeded from the main mosfet which he bridged it , not just a theory but i tried it myself , so diode or wire bridge doesn't really matter in this case . thank you
So the MOFSET is proportional? The gate had 3.3V so shouldn't the MOFSET just pass the 19.5V (or not) but it was passing just 3V if it's a just a switch how was it allowing a reduced voltage to pass? (unless switching really quick :)
There is no slot for ram upgrade?
where can i get a motherboard
eBay ?
Is this costs a lot? Pls answer me as fast as u can i rly need help
yay Sorin's back!!
Te felicito, excelente. Encontraste rápido el problema !!!! Gracias por compartir tus conocimientos
Hi, I can chang the cpu inside for a intel or one up pawer?
Nice repair video 👍
hello sir...im so happy to see u again...thank you...
Hii
I have exactly the same model of ASUS X540N that I bought a month ago
Lastweek it reached 0% i tried charging it but it dd not show life. What could be the problem with it
Your response wil be highly appriciated
If the main power rail goes directly into N-MOSFET, then what is switching that MOSFET on? If MOSFET is switched off, then there is no power if the battery is also not installed. So what is controlling the gate of MOSFET then?
Where is the battery placed on the Asus laptop ?
The Man of Techniques!
This laptop was $450 on amazon, but it's more on the level of a lenovo 100s, a baytrail based ultrabook that retailed for $199 in 2017. Maybe the pentium is faster but we're talking bottom tier components here, it's all basically the same. It's just crazy that 3 inches more display allows them to jack the price up that much.
why the fan is not working while the screen is on?
Super Video.Danke!
Salut, Sorin :) uite.. am o intrebare pt acest laptop :D :) am vazut acum ca la sfarsit dupa ce ai terminat treaba si ai conectat incarcatorul... laptopul a pornit.. asta fara ca sa mai faci.. power on din buton de la tastatura.. ?? pt ca la alte laptop-uri treaba asta nu se intampla :) ??
Awesome work this video has been a lot of help to me thank u so much
You are the Main Master Man for this Job Sir Sorin. I will always br your fan. Look at my hands, see? Its somewhat, shorted too, i guess. 😂
Upload more ! we missed you Lol .
the source and the gate is the same volt. (so the mosfet is Shortening) you dont need to do brige. you just need to replace the mosfet :-)