Hi at the end of the video when you were saying about the charging light being on my yes was fix on the connector not the white charging cable, after re-watching the end part I manged to see what you were talking about, I may be stupid but I just couldn't see the light I know that it may be trivial but pointing out where the light is would help. Thank you for listening. Overall I have learnt a lot about the schematics of the board. I'm look forward to watching the next episodes in the series of video,
This is a brilliant series, I’ve already learnt so much from it. I really appreciate you not going macro with the logic gate and gave us a much better perspective of what you were doing
Thank you so much for this - Im trying to get into the fixing of audio equipment and have been trying to find instructive videos on TH-cam to show me how technicians "go about" finding problems. Also VERY "brain opening" for me is the way you explained how the components worked together to create the correct voltage required (from previous video). Thanks xxx1000 - Regards from Iceland
Don't want to get roasted for saying this, but I find your explanation of this circuit ever so slightly better than Louis Rossmann's...his is great too, don't get me wrong - he IS the God of Macs after all - but on the other hand you also demonstrate on the board step by step where everything is :D
I usually run my hot air at 400c, and as much airflow as not to blow components away. I use a bit of distance so as not to grill things as well. Keep in mind that different air stations behave differently as well though, so you may need more or less heat. Practise will teach you when you're running too hot or too cold, you get a feel for it after a while.
Is good to practice on a faulty board first. The temperature depends on many factors such as your component size, air noozle size, air speed, flux, pad size, surrounding components, and the use of low melt solder. Some motherboards requires much higher temperature due to the type of solder they use, lead/unleaded solder. Usually 380 Celsius as a start, and preheating the board for a while by blowing the component 2 inches at the same temperature for a while and then slowly move into the component and blow the hot air on it can help a lot.
You are measuring for PP3V42 from pin 1 of the (missing) AND gate, but in the schematic pin 1 is in fact receiving SMC_BC_ACOK signal. Shouldn't you be measuring pin 5 in the lower left corner contact? (this could also better explain the low reading instead of just the bad contact with the DMM probes) If not, could you (or anyone) be so kind and point out what I'm missing here, please?
I noticed this also when comparing to the schematics im following using openboard and the schematic, it should be SMC_BC_ACOK signal he was testing, for pin 5 is PP3V42...i guess its just a mistake probably @adamant IT can you confirm?
@@anuoluwapooyelohunnu7958 No, pin1 is input signal to the AND gate and pin5 is the positive power input so both of these pins should be getting the correct readings even if the gate is removed. Pin4 is the output and thus the only pin that is affected by the gate.
It's probably to do with reuse/availability of parts, or that an AND gate chip was a commodity component, but there was no market for a single input version. Why pay for the design and manufacture of something when you could by an off-the-shelf part that can be configured to do the same thing...
Yea I see what you mean... You need SMC_BC_ACOK so the SMC has the ability to turn off the green light (so the user has visual feedback about charge status) and you can't power U6900 from that signal alone - but they could've used a simple SOT-323 to allow ACOK to switch in PP3v42. It can't be bypassed without forcing the one-wire circuit into an always-on (even when unplugged) state, but it could have been simplified. Hell, they could've picked a better U6900 that has an Enable pin on it, which ACOK could toggle.
hiya, i have one laptop board which im pretty sure stopped working due to power as its not powering up. have you email where i can reach you to help me diagnose and fix it
The software is provided by Paul Daniels. He has a channel on TH-cam. As far as schematics are concerned they are in the 9th dimension of the Chinese Universe. You have to look hard, though 😄.
I'm at this stage on my own fix, a more modern board. Diagnostics seem to report that CHGR_BMON is missing (it said reading below low point) , and I believe SMC_BC_ACOK is missing too. Any ideas on where I should start? I've measured for power rails, those are all OK. I'm thinking that the U7100 (ISL6259) has a fault since both CHGR_BMON and SMC_BC_ACKOK (I believe) are missing. I'm not sure how to measure on chips, only resistors. To clarify my board powers via button, runs normally on AC or battery, but does not charge (battery not charging) and has no green light.
Thanks for the reply. It's a Macbook Pro 13in Retina A1502, board 820-3476-A. I've checked a number of resistors on the board, they all measure within reason to the resistance they should be at (R7120, R7121, R7122 etc). I will probably also check R7110 and R7111. I can't see any visible signs of damage, no liquid or corrosion present, board looks immaculate. I began trying to measure the ISL itself but became a bit iffy on it since I don't want to damage anything further. All I know is I'm missing CHGR_BMON and BC_ACOK, while everything else on the board is telling me I should have full operation. Based on my limited knowledge, it really seems like a bad ISL (which I've ordered a new chip for).
@@Adamant_IT Ohh that reply make sense and I think it can help me a lot. Hope you make more tutorial on troubleshooting macbook in details cause I like your way of explaining things. More powers!
Hi ! I know that this is an old video but still I have a question if you have the time... is onewire is a code for the charging line ? is it universal ? and is it a logical diagnosing start point when we have pp3v42 and not the charger light ? Thanx in advance :)
I'm not sure what data is actually transmitted on the onewire line, but the important thing is that the U6900 is getting power. As far as I know, if U6900 is powered up and not physically damaged, OneWire should be fine. The next thing down the line is the SMC and PP_Bus_G3_Hot for the power up sequence.
08:30 Poor little connector on the left of the AND gate :q You should have at least give it a nice quilt made of aluminium foil so that its plastic parts didn't melt or burn.
Hope you read this, so noob questions, in this situation U6901 was bad, do I have to buy a new U6901 then? Exactly same model? Any recommended sites? Thanks!
Yea needs to be the same. eBay and Aliexpress are my usual sources. They're not the best value for money, but the most accessible for one-off purchases. Most people doing this regularly have a few unfixable "donor boards" laying around as a source of spare parts.
The best tutorial for beginners I saw on Internet. Thank you.
This series is just brilliant, can't wait to watch the following episodes :-)
As I was watching this video I was thinking to myself "I should suggest this channel to Vince".
@@jaredl2239 Or Rossmann! Lol
Absolutely fantastic. Thank you for taking the time to provide this for us beginners. You are a very good instructor. Well done sir.
Thank you for patiently sharing and teaching. This the best tutorial for beginners like me. Nothing beats problem-based learning.
Hi at the end of the video when you were saying about the charging light being on my yes was fix on the connector not the white charging cable, after re-watching the end part I manged to see what you were talking about, I may be stupid but I just couldn't see the light I know that it may be trivial but pointing out where the light is would help.
Thank you for listening.
Overall I have learnt a lot about the schematics of the board. I'm look forward to watching the next episodes in the series of video,
This guy knock's it out of the park, for laptop repair IQ!
This is by far the best series on board repair here on YT. I need to find some time now to watch the rest asap :)
This is a brilliant series, I’ve already learnt so much from it. I really appreciate you not going macro with the logic gate and gave us a much better perspective of what you were doing
Thank you so much for this - Im trying to get into the fixing of audio equipment and have been trying to find instructive videos on TH-cam to show me how technicians "go about" finding problems. Also VERY "brain opening" for me is the way you explained how the components worked together to create the correct voltage required (from previous video). Thanks xxx1000 - Regards from Iceland
Slow and steady wins the race. step by step troubleshooting done.schematic study nice.thanks
Great series of videos, very informative. Thanks!
Wow! incredible work! Many thanks to you and others making those schematics and educating everyone!
Exellent lesson! Thank you so much!
Don't want to get roasted for saying this, but I find your explanation of this circuit ever so slightly better than Louis Rossmann's...his is great too, don't get me wrong - he IS the God of Macs after all - but on the other hand you also demonstrate on the board step by step where everything is :D
Louis always says that he's not good at teaching.
Louis knows his stuff, but is not so good at teaching it, and his channel has mostly turned into a rant for a while now, i dropped it.
@@donsurlylytetrue
Thank you. You explained everything very well and it is very good again thank you
Great video ,feel like a student again .Can’t wait for the next video lesson thanks.
Incredible quality content
Nice n step by step Demonstration of dead set.
to be continued.thanks for video
Thanks so much for this series of videos!:)
Amazing tutorials mate! thanks a lot for sharing your knowledge!
Explanation is very good
Appreciate that
just saw your page, amazing content and well explained..
Very nice video.
Excellent content and instructor :-)
I am mind blown!!
Best tutorial on this topic. Thanks.
thank you! very much appreciate these videos
very nice explanation and work
Another great video. Thank you!
Nice work. Thank you
Thanks so much for these
You're our saviour
if you'd release it in the form of a book, I'd buy it
Great Video THANK YOU
Excellent 👌👌
Thank you so much brother thank you so much... love from India
Where can you find board view files and laptop schematics? Thank you
Thank u very much ❤
When reattaching 6901 and gate. What setting and heat was your hot air gun? Eg 5/8 300C. Thanks and these guys are helping me greatly.
I usually run my hot air at 400c, and as much airflow as not to blow components away. I use a bit of distance so as not to grill things as well. Keep in mind that different air stations behave differently as well though, so you may need more or less heat. Practise will teach you when you're running too hot or too cold, you get a feel for it after a while.
Is good to practice on a faulty board first. The temperature depends on many factors such as your component size, air noozle size, air speed, flux, pad size, surrounding components, and the use of low melt solder. Some motherboards requires much higher temperature due to the type of solder they use, lead/unleaded solder. Usually 380 Celsius as a start, and preheating the board for a while by blowing the component 2 inches at the same temperature for a while and then slowly move into the component and blow the hot air on it can help a lot.
Thanks a lot
what applicatin or software to see diagram on pdf?
You are measuring for PP3V42 from pin 1 of the (missing) AND gate, but in the schematic pin 1 is in fact receiving SMC_BC_ACOK signal. Shouldn't you be measuring pin 5 in the lower left corner contact? (this could also better explain the low reading instead of just the bad contact with the DMM probes) If not, could you (or anyone) be so kind and point out what I'm missing here, please?
I noticed this also when comparing to the schematics im following using openboard and the schematic, it should be SMC_BC_ACOK signal he was testing, for pin 5 is PP3V42...i guess its just a mistake probably @adamant IT can you confirm?
I think the reason he's measuring pin 1 is because, he has removed the u6901 and there's no way power would get to pin 5
@@anuoluwapooyelohunnu7958
No, pin1 is input signal to the AND gate and pin5 is the positive power input so both of these pins should be getting the correct readings even if the gate is removed. Pin4 is the output and thus the only pin that is affected by the gate.
@@tohtorizorro oh I didn't know that
@@tohtorizorro I'm just starting at this
Is the one-wire circuit just something you'll find on a MacBook or will something like a Dell Laptop also have it for the same purpose?
Why use AND logic gate if you short both inputs together anywas?
It defeats it's functiionality completly....
It's probably to do with reuse/availability of parts, or that an AND gate chip was a commodity component, but there was no market for a single input version. Why pay for the design and manufacture of something when you could by an off-the-shelf part that can be configured to do the same thing...
@@Adamant_IT I mean why not completly avoid using it and just bypass it?
Yea I see what you mean... You need SMC_BC_ACOK so the SMC has the ability to turn off the green light (so the user has visual feedback about charge status) and you can't power U6900 from that signal alone - but they could've used a simple SOT-323 to allow ACOK to switch in PP3v42.
It can't be bypassed without forcing the one-wire circuit into an always-on (even when unplugged) state, but it could have been simplified. Hell, they could've picked a better U6900 that has an Enable pin on it, which ACOK could toggle.
@@Adamant_IT Yeah just some transistor if current needs to be higher.
can u help me fixing some argb fans from lian li who got conected on 12 v 4 pin connector ? pls .
Can anyone please tell me where and how can I get BRD to file for the laptop? also, anyone has a dell latitude e6420 BRD file?
a+
Thanks
hiya, i have one laptop board which im pretty sure stopped working due to power as its not powering up. have you email where i can reach you to help me diagnose and fix it
What software do you use to see the circuit diagram
I have one question. Where are you getting these schematics and board layouts? I haven't been able to find anything worthwhile on the web.
The software is provided by Paul Daniels. He has a channel on TH-cam. As far as schematics are concerned they are in the 9th dimension of the Chinese Universe. You have to look hard, though 😄.
I'm at this stage on my own fix, a more modern board. Diagnostics seem to report that CHGR_BMON is missing (it said reading below low point) , and I believe SMC_BC_ACOK is missing too. Any ideas on where I should start? I've measured for power rails, those are all OK. I'm thinking that the U7100 (ISL6259) has a fault since both CHGR_BMON and SMC_BC_ACKOK (I believe) are missing. I'm not sure how to measure on chips, only resistors. To clarify my board powers via button, runs normally on AC or battery, but does not charge (battery not charging) and has no green light.
Thanks for the reply. It's a Macbook Pro 13in Retina A1502, board 820-3476-A. I've checked a number of resistors on the board, they all measure within reason to the resistance they should be at (R7120, R7121, R7122 etc). I will probably also check R7110 and R7111. I can't see any visible signs of damage, no liquid or corrosion present, board looks immaculate. I began trying to measure the ISL itself but became a bit iffy on it since I don't want to damage anything further. All I know is I'm missing CHGR_BMON and BC_ACOK, while everything else on the board is telling me I should have full operation. Based on my limited knowledge, it really seems like a bad ISL (which I've ordered a new chip for).
Hi! my macbook has a problem of green light only on charger but it won't turn on. Do you have step by step troubleshooting video on that?
@@Adamant_IT Ohh that reply make sense and I think it can help me a lot. Hope you make more tutorial on troubleshooting macbook in details cause I like your way of explaining things. More powers!
Congratulation
nice man :D
Hi !
I know that this is an old video but still I have a question if you have the time...
is onewire is a code for the charging line ? is it universal ? and is it a logical diagnosing start point when we have pp3v42 and not the charger light ?
Thanx in advance :)
I'm not sure what data is actually transmitted on the onewire line, but the important thing is that the U6900 is getting power. As far as I know, if U6900 is powered up and not physically damaged, OneWire should be fine. The next thing down the line is the SMC and PP_Bus_G3_Hot for the power up sequence.
❤❤❤❤❤
08:30 Poor little connector on the left of the AND gate :q You should have at least give it a nice quilt made of aluminium foil so that its plastic parts didn't melt or burn.
If you can fix these delicate motherboards, can you please fix the squeaky chair please lol
Hope you read this, so noob questions, in this situation U6901 was bad, do I have to buy a new U6901 then? Exactly same model? Any recommended sites? Thanks!
Yea needs to be the same. eBay and Aliexpress are my usual sources. They're not the best value for money, but the most accessible for one-off purchases. Most people doing this regularly have a few unfixable "donor boards" laying around as a source of spare parts.
@@Adamant_IT Thank you very much! You are an inspiration, I really enjoy your videos! Greetings from Argentina!
What magnification /light you using??
I use a Logitech BRIO webcam. The lighting in this video is just from an LED desk light - but these days I have studio lighting.
@@Adamant_IT awesome thanks man, looking for something that can zoom and focus well for working on those teeny parts lol
Why when he says "bayam" does he sounds like he's from a backwoods USA state?