Thank you to everyone who made a purchase on eBay via our affiliate link at rossmanngroup.com/ebay for helping support this type of content. Your viewership is appreciated and as always, I hope you learned something!
Louis Thank you from the bottom of my heart for sharing you knowledge . I own a computer repair shop in MA and because of your videos on TH-cam I now fix logic boards instead of replacing them.
I really didn't want to learn all this but no choice. but man you are so good. that info worth thousand of dollars Thank you Louis for making my comeback easier
Not only is Louis highly experienced and talented. He’s dead funny also. Lmao. “Then I’m gonna have to “ Actually Louis it is beneficial because you make it dead funny while teaching.
Always great videos with great explanation. Would be great if you post also a specific video talking about "3.425V "G3Hot" Supply" this would be very usefull for me at least :) should be simple circuit however I'm missing the basis Rik
It would be great to have a video that explains how this circuit works from beginning to end Here’s some doubts 820-2915B This IC (U6990) is creating the 3.425 v and it’s fed from 2 main rails PPBUS_G3H & PPDCIN_G3H right? if one of these rails is not present at D6990 does U6990 still will be able to create the 3.425v? I'm actually having 12v at ping 4 & 7 however still 0v at pin 6 & 9. PPBUS_G3H is coming from U7000.. means that if U7000 is not working properly also G3Hot Supply won’t work ? I would appreciate a lot a small video about that. Rik
supeb!!! thanks louis, i just order amscope , 3.5x90x with 5mp camera duel boom... only bcaz of you lol, plus i googled and got all the schematic and bv too...
I was just commenting the other day on your logo. & I'm going back through the one wire video and see that stuffed animal sheep. I'm curious to know about it : D Tell us about the sheep!
Hi Louis! I have seen some of your one wire circuit videos but my MBP works fine. It turns on, fan too, but it doesn't charge the battery or turn the green/orange light from the magsafe on. Battery is holding its last charge (60% right now). I already swapped the power jack inside the laptop. Charger is original Apple about 6 months old and it's working. Should I look at a different video because it isn't related to one wire circuit? It is an early 2011 13" Intel i5 MBP. I bought it brand new on April (March?) 2011. I know it's old and I already got my money's worth in return from all the work I have done with it, but, if it turns on, maybe WE can save it. (tech but no tech here, if you know what I mean) Thanks for any tip or approach to take.
I had a dead MacBook from around 2011 era. No light. I gave it to a tek friend of mine. For free. It looked great. But was a brick. I know could not have brought it back without watching Louis for about a year straight. Obv. And buying a few grand worth of equipment. Still wish I’d kept it Just in case I learn something here.
After watching this video and other videos I am now confused as to when to use flux. It seems like in the newer videos you use the flux syringe most of the time when adding and removing components.
nice videos, in one you say than you recording on laptop, why you dont record and screen same as video and microscop, and later mix before upload. ffmpeg, vlc have input for screen capturing.
Doubt I'm supposed to be even showing that I have these PDFs on the internet, would much less rather have a more "perfect" copy if you know what I mean. Also more work.
Hi Louis, Firstly I must say your video is exceptional in a sense it is very detailed and informative. Thank you for your work. As well I do have trouble finding a signal on my Macbook Air 820-3209 that has similar functionality of the ADAPTER_SENSE. In addition, I tried to find SMC_BC_ACOK but couldn't find it (this is understandable given I'm using a different board) and I found CHGR_ACOK instead. At this point I am confused with what to debug next. And would you mind guiding me on how to debug the problem? The symptom of the board is that it can be powered on (fan spinning without the chime sound and there's no display on the screen) and I am seeing no charging light on the power adapter. Thanks in advance.
Louis Rossmann Thanks I'll give it a shot. Umm... Does it mean the "ADAPTER_SENSE" signal is processed on the DC in board rather than going through the flex cable? If it is later what would be the corresponding SENSE signal? And it would be great if you could post a video regarding tracing the adapter signal on Mac Air. :)
Wow, this is great instructional video! Thanks for sharing your experience. I was able to check almost everything but on my old Macbook A1278 2008 mobo 820-2327 the "one wire circuit" looks different on schematics. The symptoms are strange: dim green light on magsafe, powers only with the battery on but charges normally. The problem was caused by a fried old Masafe adapter and i still didn't figure out what is the problem. I get 0V on adapter sense, is that normal?
+Louis Rossmann I used to be a chemist but i like to learn always something different... Thanks to your videos i have learned a lot and for sure i won't surrender so easily until i will find the solution even if this it would cost me one year of tests! :) Thanks Louis you are a great guy!
+Louis Rossmann Following the rabbit hole of the PP18V5 around the Q6910 i have found this: it.tinypic.com/r/10pvoxz/9 It looks like that nothing is coming out from it so i came to the conclusion that it is blown. I have no tension (0.03V) also on U6915. I am right?
Am I the only one who saw the EMPTY fugly pads right above the caps pads he removed? Or is that just no connection? Wouldn't that affect the smc and be a reason why it works bypassed?
the smc looks like what they use to call embeded controller in another laptop... did annyone manage to crak/rescrive the firmware of the SMC? I'm thinking that the apple has only a couple of models and should be easier to do... for acers there was a russian guy that manage to crack everything...
I'm sure that there is a way tu burn a new chip, they do it... I don't know if there is sommekind of fuse for extracting the hex from inside... I don't work with apples... I'm in a different field but have the same problems with custom asics, custom firmware for chips with the fuses burned ecc... unfortunately I don't have used dismissed boards to recover the chips from...
I have a 820-2936A Motherboard. The problem i have is there is a dim green light. tried doing all the resets SMC and stuff but the thing i notice that when i connect the charger the battery is not charging and also not going down. i previously had water damage but managed to dry up and was working fine abt a year or 2. i want to take some voltages and i do have the schematic but i cannot find the components to measure. possible to help or advice?
with the u7000 (ISL6959) removed, should you have ANYTHING on Pad 14 (SMC_BC_ACOK)...? I had the U7000 (Got VERY hot!) on the board and have nothing on PIN 14... removed u7000 and plugged charger in and on pad 14 there is 3.4x volts at the pad... is this even remotely possible?
Louis Rossmann ok, so the volt from the magsage is 16.5 16.5 ground ground and sense ,does the sense have a volt? louis when people from mac see you they will contract you , i hope you never forget you people and youtube, i like you videos thanks
Hey Louis, really great video! Thanks for all the effort that you put into posting these. Thanks to you, I was able to fix my Macbook Pro power problem. It saved me weeks of frustration. I even posted a summary of my (ultimately happy) experience on my blog: www.jpuderer.net/2015/09/repairing-macbook-pro-yes-it-possible.html
So I have a question that I am hoping you may be able to answer. it is about the onewire circuit or any other circuit for that matter. In my example I will use onewire and the u6990 IC ST PM6640. So question is, according to schematics it appears that pins 6 and maybe also pin 9 whichis reference supply the 3.42v used for the ppv342_G3H. Lets say there is a short to ground somewhere in the circuit maybe a capacitor. Wouldn't you still be able to check for the voltage at L6995 either pin 1 or 2 or right at the pin 6 of the PM6640? Since there is a short to ground wouldn't voltage still flow out of PM6640 and through the inductor and than stop somewhere along the way when it hits the short to ground? Meaning couldn't you use a multimeterr set to DCV and test for the 3.42v at pin 6 or pin 1 or pin 2 of the inductor? Obviously the circuit wouldn't work because it is going to go to ground instead of where it should be going but wouldn't you be able to see the voltage coming out of the PM6640? \ In a board I recently did wind up repairing I got no voltage from PM6640. I swapped the chip prior to looking for a short. After replacing the chip I still had no voltage out of PM6640. I than checked for short and found short of the pin 2 side of L6995. Turns out a capacitor had shorted to ground and once I replaced it green light voltage the whole nine yards. I just in my mind cannot figure why the voltage wasn't there prior to fixing the short. I know that electricity wants to go to ground so wouldn't the PM6640 still spit out the voltage and it would just flow endlessly to ground? Thanks for your help!
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Thank you to everyone who made a purchase on eBay via our affiliate link at rossmanngroup.com/ebay for helping support this type of content. Your viewership is appreciated and as always, I hope you learned something!
Louis
Thank you from the bottom of my heart for sharing you knowledge . I own a computer repair shop in MA and because of your videos on TH-cam I now fix logic boards instead of replacing them.
Amazing. Keep it up!
Freaking excellent. I don't have these issues, but dude.. I love to learn and this lets me know how my machine works :)
Thanks Louis!
I love how you say A-COK instead of AC OK. Love your vids!
+Zzyzx Wolfe Thanks for watching!
smc bypass mode, learnt something new today
One more great video thanks Louis.
I really didn't want to learn all this but no choice. but man you are so good. that info worth thousand of dollars
Thank you Louis for making my comeback easier
Great video Louis!
Not only is Louis highly experienced and talented. He’s dead funny also.
Lmao. “Then I’m gonna have to “
Actually Louis it is beneficial because you make it dead funny while teaching.
Excellent vid
Always great videos with great explanation.
Would be great if you post also a specific video talking about "3.425V "G3Hot" Supply" this would be very usefull for me at least :) should be simple circuit however I'm missing the basis
Rik
Ask more specific questions and a video will be created accordingly.
It would be great to have a video that explains how this circuit works from beginning to end
Here’s some doubts
820-2915B
This IC (U6990) is creating the 3.425 v and it’s fed from 2 main rails PPBUS_G3H & PPDCIN_G3H right?
if one of these rails is not present at D6990 does U6990 still will be able to create the 3.425v? I'm actually having 12v at ping 4 & 7 however still 0v at pin 6 & 9.
PPBUS_G3H is coming from U7000.. means that if U7000 is not working properly also G3Hot Supply won’t work ?
I would appreciate a lot a small video about that.
Rik
you do not need ppbus_g3h in order to get pp3v42_g3h.
And U7000 fully working?
I'm doing a video tonight on PP3V42 to explain this a little bit. U7000 does not have to work for PP3V42 to be present with a charger plugged in.
supeb!!! thanks louis, i just order amscope , 3.5x90x with 5mp camera duel boom... only bcaz of you lol, plus i googled and got all the schematic and bv too...
I was just commenting the other day on your logo. & I'm going back through the one wire video and see that stuffed animal sheep. I'm curious to know about it : D Tell us about the sheep!
Very informative thank you for uploading.
Great Videos, please keep them coming!
Subscribed!
and in you're field you're lucky because you find boards to buy... that and the fact that you find the schematics make's life much more easyer...
Hi Louis!
I have seen some of your one wire circuit videos but my MBP works fine. It turns on, fan too, but it doesn't charge the battery or turn the green/orange light from the magsafe on. Battery is holding its last charge (60% right now). I already swapped the power jack inside the laptop. Charger is original Apple about 6 months old and it's working. Should I look at a different video because it isn't related to one wire circuit?
It is an early 2011 13" Intel i5 MBP. I bought it brand new on April (March?) 2011. I know it's old and I already got my money's worth in return from all the work I have done with it, but, if it turns on, maybe WE can save it. (tech but no tech here, if you know what I mean)
Thanks for any tip or approach to take.
I had a dead MacBook from around 2011 era. No light. I gave it to a tek friend of mine. For free. It looked great. But was a brick. I know could not have brought it back without watching Louis for about a year straight. Obv.
And buying a few grand worth of equipment.
Still wish I’d kept it Just in case I learn something here.
After watching this video and other videos I am now confused as to when to use flux. It seems like in the newer videos you use the flux syringe most of the time when adding and removing components.
What OS do you use? It kinda looks like some Linux distro. Just out of curiosity
nice videos, in one you say than you recording on laptop, why you dont record and screen same as video and microscop, and later mix before upload. ffmpeg, vlc have input for screen capturing.
Doubt I'm supposed to be even showing that I have these PDFs on the internet, would much less rather have a more "perfect" copy if you know what I mean.
Also more work.
Hi Louis,
Firstly I must say your video is exceptional in a sense it is very detailed and informative. Thank you for your work.
As well I do have trouble finding a signal on my Macbook Air 820-3209 that has similar functionality of the ADAPTER_SENSE. In addition, I tried to find SMC_BC_ACOK but couldn't find it (this is understandable given I'm using a different board) and I found CHGR_ACOK instead. At this point I am confused with what to debug next. And would you mind guiding me on how to debug the problem?
The symptom of the board is that it can be powered on (fan spinning without the chime sound and there's no display on the screen) and I am seeing no charging light on the power adapter.
Thanks in advance.
Corrosion on 821-1477 DC in flex cable, or bad DC in board. Most of the time corroded flex.
Louis Rossmann Thanks I'll give it a shot. Umm... Does it mean the "ADAPTER_SENSE" signal is processed on the DC in board rather than going through the flex cable? If it is later what would be the corresponding SENSE signal? And it would be great if you could post a video regarding tracing the adapter signal on Mac Air. :)
Wow, this is great instructional video! Thanks for sharing your experience. I was able to check almost everything but on my old Macbook A1278 2008 mobo 820-2327 the "one wire circuit" looks different on schematics. The symptoms are strange: dim green light on magsafe, powers only with the battery on but charges normally. The problem was caused by a fried old Masafe adapter and i still didn't figure out what is the problem. I get 0V on adapter sense, is that normal?
+Rossano Balloco That uses different onewire circuit, but you will figure it out if you look hard enough!
+Louis Rossmann I used to be a chemist but i like to learn always something different... Thanks to your videos i have learned a lot and for sure i won't surrender so easily until i will find the solution even if this it would cost me one year of tests! :) Thanks Louis you are a great guy!
Q6910 is first hint
+Louis Rossmann Following the rabbit hole of the PP18V5 around the Q6910 i have found this: it.tinypic.com/r/10pvoxz/9 It looks like that nothing is coming out from it so i came to the conclusion that it is blown. I have no tension (0.03V) also on U6915. I am right?
do you have a solution to remove apple id from desktop pc apple mac 2007 whitout apple id from previous owner ?
The "power button" on the keyboard? Is this a Mac keyboard thing?
Am I the only one who saw the EMPTY fugly pads right above the caps pads he removed? Or is that just no connection? Wouldn't that affect the smc and be a reason why it works bypassed?
Why do You conclude that SMC is at fault, when it powers up only in SMC bypass?
BR
Dagnis Lazdins yes i like to know this as well. i thought when the fans are spinning. it should mean SMC is working right?
Ohm's law baby. It works.
If you don't mind me asking, where are the location where you measure the 12v,5v,and 3.3v
Find boardview for your board, search for PPBUS_G3H, PP5V_S5, PP5V_S3, PP3V3_S5, PP3V3_S3, PP3V42_G3H
the smc looks like what they use to call embeded controller in another laptop... did annyone manage to crak/rescrive the firmware of the SMC? I'm thinking that the apple has only a couple of models and should be easier to do... for acers there was a russian guy that manage to crack everything...
I'm sure that there is a way tu burn a new chip, they do it... I don't know if there is sommekind of fuse for extracting the hex from inside... I don't work with apples... I'm in a different field but have the same problems with custom asics, custom firmware for chips with the fuses burned ecc... unfortunately I don't have used dismissed boards to recover the chips from...
I have a 820-2936A Motherboard. The problem i have is there is a dim green light. tried doing all the resets SMC and stuff but the thing i notice that when i connect the charger the battery is not charging and also not going down. i previously had water damage but managed to dry up and was working fine abt a year or 2. i want to take some voltages and i do have the schematic but i cannot find the components to measure. possible to help or advice?
Did you figure out the issue? Having the same symptoms but never had any water damage.
Love this. :)
with the u7000 (ISL6959) removed, should you have ANYTHING on Pad 14 (SMC_BC_ACOK)...? I had the U7000 (Got VERY hot!) on the board and have nothing on PIN 14... removed u7000 and plugged charger in and on pad 14 there is 3.4x volts at the pad... is this even remotely possible?
+William Bailey If you remove a buck controller and apply power to the board it is done for. Never do that.
+Louis Rossmann Awesome... lesson learned...
hi, i cant find macbook unibody (late 2009) 13" model n°A1331 schematics anywhere... somebody help???
i have a question the 3.42 v start in the macsafe?
raulmorel1 No.
Louis Rossmann
ok, so the volt from the magsage is 16.5 16.5 ground ground and sense ,does the sense have a volt?
louis when people from mac see you they will contract you , i hope you never forget you people and youtube, i like you videos thanks
10:07, Am I the only one to notice the missing component?
"Power fan?"
Hey Louis, really great video!
Thanks for all the effort that you put into posting these. Thanks to you, I was able to fix my Macbook Pro power problem. It saved me weeks of frustration.
I even posted a summary of my (ultimately happy) experience on my blog: www.jpuderer.net/2015/09/repairing-macbook-pro-yes-it-possible.html
So I have a question that I am hoping you may be able to answer. it is about the onewire circuit or any other circuit for that matter. In my example I will use onewire and the u6990 IC ST PM6640. So question is, according to schematics it appears that pins 6 and maybe also pin 9 whichis reference supply the 3.42v used for the ppv342_G3H. Lets say there is a short to ground somewhere in the circuit maybe a capacitor. Wouldn't you still be able to check for the voltage at L6995 either pin 1 or 2 or right at the pin 6 of the PM6640? Since there is a short to ground wouldn't voltage still flow out of PM6640 and through the inductor and than stop somewhere along the way when it hits the short to ground? Meaning couldn't you use a multimeterr set to DCV and test for the 3.42v at pin 6 or pin 1 or pin 2 of the inductor? Obviously the circuit wouldn't work because it is going to go to ground instead of where it should be going but wouldn't you be able to see the voltage coming out of the PM6640? \
In a board I recently did wind up repairing I got no voltage from PM6640. I swapped the chip prior to looking for a short. After replacing the chip I still had no voltage out of PM6640. I than checked for short and found short of the pin 2 side of L6995. Turns out a capacitor had shorted to ground and once I replaced it green light voltage the whole nine yards. I just in my mind cannot figure why the voltage wasn't there prior to fixing the short. I know that electricity wants to go to ground so wouldn't the PM6640 still spit out the voltage and it would just flow endlessly to ground? Thanks for your help!