So you saying if bq sees a little raise on resistance it will shut down battery charging? That's makes sense, I thought it would be something related to Hertz.
SiE, we understand your point on the video few months ago, where second Mosfet shorted would cause battery not to charge. But the first one? That is really new. I think Sorin didn’t wait long enough and the charging would eventually start.
There is transistor that carry the voltage to battery if the ic chip detected short on second mosfet it will be not send signal to transistor to be open if you short the second mosfet you should be short on the transistor to.
I've the same problem a compaq laptop (hp) turn on but doesn't charge i'll check the second mosfet..sure i need to check if the battery it is shorted.. thanks very much for your time
Hi Sorin i am a recent recruit to your very interesting channel and it wet my appetite to learn more, can you tell me where i can get chip recognition information and how i go about to get a particular schematic information please. Many thanks for a very interesting program. kind regards Mark from Wigan
@Electronics repair school - I am so glad you made this video; I have had a Chromebook by HP that does exactly this issue; runs fine on AC power, but won't charge battery! If I manually charge the battery with my bench power supply, the Chromebook will work fine on the battery no problem, but won't charge it! I was tearing my hair out as I can't fund a schematic for this and could not find anything on the internet or youtube to help me diagnose the problem (results only show info for "no power" but not "no charging"!
Yes Sorin i repeat if one of the mosfet is shorted, the laptop will not charge the battery and it will never unless the charger ic is faulty somehow...I've been telling people on my channel to stop jumping mosfets, it so unprofessional and amateur thing to do...Always give customers the best I know people resist change, they block themselves from learning new things, and exploring new paths...LET SAY NO TO JUMPING OF MOSFETS...I use to jump mosfet as well when i first started to repair laptops but after few months i understood that the charger ic is so smart, it senses and communicate with those 2 mosfets, if one is shorted, it will never allow power to pass
I understand but I used to bypass two mosfets and it charges , can you explain please ? I know in newer laptop the BQ chip won't allow that but how about older laptops ? I tried it myself in hp pro book board which first two mosfets was burned and welded to the board and I bypassed them with jumber wire and laptop was working and charging
hello Sorin question for you my friend has a HP laptop 17 inch D4L46EA#ABF hes having problems with his keyboard he sort of wacked it and run his hand over the keys as it wasnt responding he now has a problem with his keyboard cannot put his pin code in without one or more numbers appearing its just not working as it should what could be his problem will he need to replace his keyboard or try to reload his laptop look forward to your reply
Thanks a lot, I have two laptops that do not charge. I was suspecting this kind of issue but didn't look because you said a few times this should not be the case. Great that you found this :). Thanks for sharing. Would love to know more causes for laptop powering on and battery not charging. I am sure the batteries are good, one Toshiba actually has had 2 replacements to try, no luck. Was thinking to check charging wires with an oscilloscope :). Thanks a lot of sharing and glad you and others learn from each other!
I have fixed this problem before first open the battery disconnect the positive of the battery from the battery circuit connect it to the battery positive pin with a fuse wire, The battery will then have voltage connection at its positive and negative pins and the battery clock pins etc will be present and working. Using two bc 548 transistors a resistor and a zender diode of the correct values make a voltage regulator connect the input to 19 volts at board input connect earth to the board the connect the regulator output to the positive of the battery connector. Works on my hp same laptop same charging circuit shows charge percentage when it is on works on battery no problems.
Quick Question. Please what happens when you replace P channel mosfet with N Channel? Will it render the motherboard useless? Can it cause further damage to other components? How do you distinguish P Channel and N Channel mosfets without schematics? I know there are numbers on the mosfet and by typing those numbers on the mosfet in google, you can actually read the datasheet and know. BUT.. I've seen some mosfet numbers that don't have datasheet available on google. How then can one be able to always distinguish N Channel and P Channel mosfets.
Hi sorin thanks for sharing I've learnt alot from you, actually the chip that controls the two mosfets has a special mosfet short circuit protection, the mosfet has an Rds(ON) resistance when it conduct which create a voltage drop, current monitoring feature of the chip is achieved through monitoring the voltage drop across RDS(on) of the MOSFETs after a certain amount of blanking time. In case of a MOSFET short circuit, the overcurrent condition is sensed by two comparators and two counters are triggered. After seven short circuit events, the charger is latched off and the two MOSFETs are turned off to disconnect the adapter from the system yet another mosfet is turned on to connect the battery pack to the system (i quoted it from the bq24780s datasheet), so obviously what happened the mosfets when shorted the Rds(ON) resistance went so low then the voltage drop is greatly reduced the chip got the information and the adapter got disconnected ,and the laptop works on the battery.
When I test the voltage with a multimeter from the charger, it shows 20v, when I plug it in the laptop, the voltage drops and starts fluctuating (not steady) betwween different numbers ranging from 13-15v but does not reach 0v and does not turn on the laptop. All it does is make the charger light flicker. The laptop works properly as I used another charger in it. Its a lenovo, and I now have 2 chargers doing the exact the same thing. My guess is that its a component inside the AC which is failing. Any knows what the problem might be?
You forgot to check battery voltage, when the laptop was with wire. It is possible if it was too low to not charging. Maybe I am wrong I am not professional.
Hi ! Great video it's awesome to follow your real train of thought, thank your for this ! At 21:23, why don't you simply power the laptop DC jack connector with the power supply ? (you could solder the "adapter" in 10 seconds if you don't already have one)
Ey sorin , I always question my self why you dont check the mosfet you take out. Well I appreciate you did it today. Or at least try it before misplaced hahaha . Good video
Can someone help me to figure out what is the problem on my laptop? The model is travelmatep214 and I checked on the 2nd mosfet, the drain is 19v but the source is 10.5v. And it doesn't power on my laptop even if I plugged my charger without the battery. pls help
@@thinkverse991 Are 3.3V and 5V power rails working? If so check for shorts on all the other power rails. If no shorts, verify that all the required voltages are coming to the charging chip.
Sorin, A plug-in mains power monitor is an easy way to check battery charging ( and other things too). Just plug your laptop charger into it and watch for the power reading change with the battery plugged or unplugged.
Does the gate need some feedback ? so if you just short the mosfet, that signal pin is open and thus chip wont allow charging? but laptop will get power and run. The two mosfets sort of work together? so shorting one will stop any charging?
Nice work, Sorin you should talk about the right to repair do you think it should be a law that forces the producer to make products more easy to repair, also force them to sell all the components required for repair schematics included. Did you see the last surface on ifixit it has 0 score for repairability you have to destroy the case to get inside is this how thigs should be, also apple is trying to do with new products . What is your point of view?
HI, that is funny, 0.9 V was what I find everywhere on the motherboard I tested, then I discovered that it came from the gate or the output , of the first mosfet, and that voltage was all along the 19 V rail. SO I guess if I find again that value I will think of the shorted mosfet first
we are all wrong at times. dont worry about it. at least you can be a man and admit it. nobody is perfect. i respect you for this. so dont worry when you make a mistake. we dont learn if we dont make mistakes.
Wouldn't you be better off leaving the faulty MOSFET in place and putting the wire link across it? Removing the MOSFET totally and then just putting a wire link there how is the signal supposed to work?
2nd mosfet no charging? ... No. First time on the "fuse" you didn't try long enough and the charge control circuitry just didn't start charging, yet. 2nd time on the replaced mosfet you tried for longer and then it eventually started to charge. Remember, those mosfets at the input are just protection. One cuts out when there's too much current, the other one cuts out when the polarity is wrong.
Sorin has waited 32 seconds with the "fuse" to see if the battery starts charging. With the MosFet replaced, after 13 seconds the battery began to draw current.
You should educate yourself in electronics, and after that than you could venture yourself in repairing things. If you don't understand why the second mosfet is shorted, then you shouldn't offer repair services to ANYONE!
Hi Sorin, I am proud of you :)
So you saying if bq sees a little raise on resistance it will shut down battery charging? That's makes sense, I thought it would be something related to Hertz.
@@SiETechNotebookReparatur or bq24780 page 21
SiE, we understand your point on the video few months ago, where second Mosfet shorted would cause battery not to charge. But the first one? That is really new. I think Sorin didn’t wait long enough and the charging would eventually start.
@@professoringles985 no, the wire he placed has for sure lower resistance comparing to conducting mosfet.
@@asv5769 Here was also the second MosFet shorted.
NO way, sorin replaced the mosfets :D now i seen everything! :D
you forget legend of portuguese people, good to see you again :)
thank you sorin
Hello Sorin,welcome back!
Love your honesty Sorrin. Wish you was a politician as they never admit when they are wrong.
Thanks i learned new again.
There is transistor that carry the voltage to battery if the ic chip detected short on second mosfet it will be not send signal to transistor to be open if you short the second mosfet you should be short on the transistor to.
I like your video... I'm becoming pro by following you bumper to bumper
I've the same problem a compaq laptop (hp) turn on but doesn't charge i'll check the second mosfet..sure i need to check if the battery it is shorted.. thanks very much for your time
Hi Sorin i am a recent recruit to your very interesting channel and it wet my appetite to learn more, can you tell me where i can get chip recognition information and how i go about to get a particular schematic information please. Many thanks for a very interesting program. kind regards Mark from Wigan
Great job 👍
Thanks
Thank you Sorin for sharing your knowledge with us :) greetings from Brazil. Best wishes
@Electronics repair school - I am so glad you made this video; I have had a Chromebook by HP that does exactly this issue; runs fine on AC power, but won't charge battery! If I manually charge the battery with my bench power supply, the Chromebook will work fine on the battery no problem, but won't charge it!
I was tearing my hair out as I can't fund a schematic for this and could not find anything on the internet or youtube to help me diagnose the problem (results only show info for "no power" but not "no charging"!
I too have a similar problem , it says charging but the percentage is not increasing. I wonder what it could be . Battery is also new .
Very nice explane
nice heatsync, learning from apple
😊🤣🤣😂😊At last you believe me, great video👍
Thanks for sharing, nice video
love you sorin
At last, you back :D
Yes Sorin i repeat if one of the mosfet is shorted, the laptop will not charge the battery and it will never unless the charger ic is faulty somehow...I've been telling people on my channel to stop jumping mosfets, it so unprofessional and amateur thing to do...Always give customers the best
I know people resist change, they block themselves from learning new things, and exploring new paths...LET SAY NO TO JUMPING OF MOSFETS...I use to jump mosfet as well when i first started to repair laptops but after few months i understood that the charger ic is so smart, it senses and communicate with those 2 mosfets, if one is shorted, it will never allow power to pass
I understand but I used to bypass two mosfets and it charges , can you explain please ? I know in newer laptop the BQ chip won't allow that but how about older laptops ? I tried it myself in hp pro book board which first two mosfets was burned and welded to the board and I bypassed them with jumber wire and laptop was working and charging
Thanks!!
hello Sorin question for you my friend has a HP laptop 17 inch D4L46EA#ABF hes having problems with his keyboard he sort of wacked it and run his hand over the keys as it wasnt responding he now has a problem with his keyboard cannot put his pin code in without one or more numbers appearing its just not working as it should what could be his problem will he need to replace his keyboard or try to reload his laptop look forward to your reply
Thanks a lot, I have two laptops that do not charge. I was suspecting this kind of issue but didn't look because you said a few times this should not be the case. Great that you found this :). Thanks for sharing. Would love to know more causes for laptop powering on and battery not charging. I am sure the batteries are good, one Toshiba actually has had 2 replacements to try, no luck. Was thinking to check charging wires with an oscilloscope :). Thanks a lot of sharing and glad you and others learn from each other!
what if it see current on current resistor before it send signal to open mosfets
Thank you Master Sorin!!!
It is a kind and unselfish heart that will share such knowledge and experience. I have learnt a lot from you. Thanks a lot and God bless ...
I have fixed this problem before first open the battery disconnect the positive of the battery from the battery circuit connect it to the battery positive pin with a fuse wire, The battery will then have voltage connection at its positive and negative pins and the battery clock pins etc will be present and working.
Using two bc 548 transistors a resistor and a zender diode of the correct values make a voltage regulator connect the input to 19 volts at board input connect earth to the board the connect the regulator output to the positive of the battery connector.
Works on my hp same laptop same charging circuit shows charge percentage when it is on works on battery no problems.
More info. Video if u can
Nice Video 😊
i have learnt a lot from you Mr Sorin.... thanx a million
Can there be no gate signal?
did you solder your wire back on battery input?
In the life you will always learn something new. Good video again ty Sorin.
Quick Question. Please what happens when you replace P channel mosfet with N Channel? Will it render the motherboard useless? Can it cause further damage to other components? How do you distinguish P Channel and N Channel mosfets without schematics? I know there are numbers on the mosfet and by typing those numbers on the mosfet in google, you can actually read the datasheet and know. BUT.. I've seen some mosfet numbers that don't have datasheet available on google. How then can one be able to always distinguish N Channel and P Channel mosfets.
P channel usually have odd number at the end
@@shomi75 Thank you so much for the answer.
Sorin Happy you are back.
Dit you had a nice holiday week (gaming 24/7😁😁)
Monday is a hard day
Sorin .... Im waiting for your dogggieee masterpiece... Hahaaa. Thank u for your time for us...
Hi sorin thanks for sharing I've learnt alot from you, actually the chip that controls the two mosfets has a special mosfet short circuit protection, the mosfet has an Rds(ON) resistance when it conduct which create a voltage drop, current monitoring feature
of the chip is achieved through monitoring the voltage drop across RDS(on) of the MOSFETs after a certain amount of blanking time. In case of a MOSFET short circuit, the overcurrent condition is sensed by two comparators and two counters are triggered. After seven short circuit events, the charger is latched off and the two MOSFETs are turned off to disconnect the adapter from the system yet another mosfet is turned on to connect
the battery pack to the system (i quoted it from the bq24780s datasheet), so obviously what happened the mosfets when shorted the Rds(ON) resistance went so low then the voltage drop is greatly reduced the chip got the information and the adapter got disconnected ,and the laptop works on the battery.
Thank you, now make sens
When I test the voltage with a multimeter from the charger, it shows 20v, when I plug it in the laptop, the voltage drops and starts fluctuating (not steady) betwween different numbers ranging from 13-15v but does not reach 0v and does not turn on the laptop. All it does is make the charger light flicker. The laptop works properly as I used another charger in it. Its a lenovo, and I now have 2 chargers doing the exact the same thing. My guess is that its a component inside the AC which is failing. Any knows what the problem might be?
Usually bad caps in the charger.
@@SinsBird or lose solder joints in the high voltage side of the charger starting with the input or the big filtering capacitor
What does Sorin mean by 'he saw it in the chat'? Is this a video of a live broadcast? How to see the live version with the chat?
Either discord or comment section
@@SinsBird OK thanks. It seems like he is talking live to a chat forum but maybe he is just talking generally.
I don't believe others you always right.
can we put 3gb of ram in laptop?like 2gb of 1 and 1gb of 1?
yep!
You forgot to check battery voltage, when the laptop was with wire. It is possible if it was too low to not charging. Maybe I am wrong I am not professional.
Hi ! Great video it's awesome to follow your real train of thought, thank your for this !
At 21:23, why don't you simply power the laptop DC jack connector with the power supply ? (you could solder the "adapter" in 10 seconds if you don't already have one)
Its not possible. The 3.3 middle pin responsible for charger type detection will not be present and hence the laptop will not charge.
@@davidasare6841 All right !
I would have sent 19v to the middle pin :D
👍👍👍
Finally You're back , another great video
sir sorin i wish we had a lesson about the bq chip and charging system and the battery charging system and battery powering the loptop
Hey sorin
Hello Soren, my name is Karl, I’m a refrigeration/HVAC mechanic (17 years), I’m trying to learn electronics, you are helping me a lot. Thank you.
The customer who owns this laptop is a Nigerian or related to. Cus that name is a Nigerian name
Sorin always talks of "super ion"/ "superio" / but l don't actually get the name properly. can anyone help me with the name?
Super io
Or EC chip embedded controller
@@SinsBird thank very much
@@AnonymousRepair thank you very much
different mosfet, looks like you replace n channel with p channel mosfet
I think that you are right. He put p channel on n channel place and I don't know how that thing works
Thank you very much sir, i have a similar issue, i hope this video will help me to fix those issues.
Ey sorin , I always question my self why you dont check the mosfet you take out. Well I appreciate you did it today. Or at least try it before misplaced hahaha . Good video
sorin just one request if you understand why it is not charging then please make a video and tell us how the thing works.
Where are my Mosfets...
Nice job Sorin . I think you should wait a little bit before replacing the second mosfet to make the current flow to dead battery
That's the problem with taking too many vacations! we forget... ;) too relaxed ? :) Thanks for your videos Sorin !
it's gone
A slightly different design, one in a 100 laptops repaired.
Your rules still work for most machines.
🤩😍😍😍
Can someone help me to figure out what is the problem on my laptop? The model is travelmatep214 and I checked on the 2nd mosfet, the drain is 19v but the source is 10.5v. And it doesn't power on my laptop even if I plugged my charger without the battery. pls help
Sounds like the mosfet is not getting turned on.
@@SinsBird I used dc power supply, I think i fried my laptop using my old hot air station. it’s not turning on now 😅
@@thinkverse991 Are 3.3V and 5V power rails working? If so check for shorts on all the other power rails. If no shorts, verify that all the required voltages are coming to the charging chip.
@@thinkverse991 Is the first mosfet shorted?
@@SinsBird Not Sir
Sloppiness is taking it's revenge... I remember someone sent you a nice component board sometime ago....😇
Sorin a Legend in His Own Time
I always learn more from your mistakes than your success. Thank you
Sorin, A plug-in mains power monitor is an easy way to check battery charging ( and other things too). Just plug your laptop charger into it and watch for the power reading change with the battery plugged or unplugged.
Probably you missed that, but in the end, you can see customer name on laptop screen.
How ru
Does the gate need some feedback ? so if you just short the mosfet, that signal pin is open and thus chip wont allow charging? but laptop will get power and run. The two mosfets sort of work together? so shorting one will stop any charging?
So the question now becomes: How many laptops have you sent to customers that cant charge ?
Nice work, Sorin you should talk about the right to repair do you think it should be a law that forces the producer to make products more easy to repair, also force them to sell all the components required for repair schematics included. Did you see the last surface on ifixit it has 0 score for repairability you have to destroy the case to get inside is this how thigs should be, also apple is trying to do with new products . What is your point of view?
You could of just check if the voltage is going up on the battery. That is enough proof from me
some times youre cunfusin
hahahaha thanks you sir
HI, that is funny, 0.9 V was what I find everywhere on the motherboard I tested, then I discovered that it came from the gate or the output , of the first mosfet, and that voltage was all along the 19 V rail. SO I guess if I find again that value I will think of the shorted mosfet first
I wish i could understand this i am fasinated
we are all wrong at times. dont worry about it. at least you can be a man and admit it. nobody is perfect. i respect you for this. so dont worry when you make a mistake. we dont learn if we dont make mistakes.
Wouldn't you be better off leaving the faulty MOSFET in place and putting the wire link across it? Removing the MOSFET totally and then just putting a wire link there how is the signal supposed to work?
2nd mosfet no charging? ... No. First time on the "fuse" you didn't try long enough and the charge control circuitry just didn't start charging, yet. 2nd time on the replaced mosfet you tried for longer and then it eventually started to charge.
Remember, those mosfets at the input are just protection. One cuts out when there's too much current, the other one cuts out when the polarity is wrong.
Sorin has waited 32 seconds with the "fuse" to see if the battery starts charging. With the MosFet replaced, after 13 seconds the battery began to draw current.
is the first input mosfet responsible for polarity safety and the second one is for current protection?
You should educate yourself in electronics, and after that than you could venture yourself in repairing things. If you don't understand why the second mosfet is shorted, then you shouldn't offer repair services to ANYONE!
why are you here watching then ?
why the second mosfet is shorted Mr.Donkey ?
keeping it real :)
5th
Second
you thought you are dodgy no you are fool