When a MOSFET sends 12v to my framebuffer :(

hi so I haven't done a lot of board repair video in a while you may have noticed that I've been going through all of my older edited videos and I will not edit videos but I've been going through my old recordings and editing them rather than doing some new recordings so I haven't done a live board repair video in a while but we're gonna get to one with this board right here we're gonna try to figure out what's going on with it and I'm gonna explain it to you as with all these board repairs live on camera so this is a 15 inch retina from about 2013 2014 and the issue with it when we go to plug it in is that you get a light on the charger but it doesn't turn on so we're gonna go over fixing it so that it does turn on so what I always say is that you should take a quick look over the board before you turn your brain on this is a concept that I think I've been explaining to a lot of the students that come for the tutoring but it's something that I don't think I've been getting across properly to the people who actually watch the channel so I'd like to do something we're called brain on brain off so one of the ways that I deal with the way my business works so as I've explained in some of the prior videos I'm the only person here doing all the board repairs my years of attempts at finding somebody qualified have all usually failed with either people lying about their experience or coming for training and then within a 1 of 6 weeks running away screaming at the horror the horror of doing my job of working for me anyway so I do all the work here in the way that I'm able to get all of that done in the way that I'm able to not burn myself out is I go back and forth between brain on and brain off so in order to not get tired I try to spend as much time as I can on what I call the brain off mode where I don't have a schematic open I'm not thinking about which pawel rail comes first or what the sequence of signals are or even just looking for things on a schematic I really try to limit using my brain until I absolutely need to so I do a lot of work in this mode called brain off where I'm not necessarily thinking as I'm going through what it is that I need to do so let's go through that with this board so the first thing that I do is I look over the board to see if there's a spill because even though most people come in saying I've never spilled something this is kind of thing where they think that were the Apple store you see it's like they people are kind of used to lying because they think if they lie they'll get something for free or that'll be it's just kind of something that I think is in grains and in people's heads and they carry over into these situations where there is where there's no chance of warranty like I don't really care if the issue with the machine was a liquid spill or if the issue with the machine is something else I'm you know I'm going to charge you anyway but one of the most common things are gonna here is that I didn't spill anything no I didn't spill anything this person was really adamant that they had never spilled something on their machine even though it smelled smelled like Starbucks but they know so the first thing I'm going to do is do what dr. house says and not believe them we're gonna look and see if as house says if everybody lies so let's take a look at this under the microscope and my microscope looks funny piece of so let's see are you gonna look good when I plug you back in turn you on yeah we get alright so let's try unplugging that here we go this looks a lot better I really have no right to open broadcaster is free and being free you know it's it's going to it's it's gonna do some silly sometimes let me just make sure that it's in focus for me now I'm gonna make sure that it's in focus for you and we're gonna set it up and we're gonna go through this board so you tell me if you see anything that looks a little out of the out of what you would usually perceive as ordinary so we're gonna go through no-spill maybe he is maybe the person's right maybe they're not lying after all maybe I am just being an customers don't lie man may never make stuff up okay we're gonna go to the other side of the board what I feel like the noises that great a Andrey makes can apply to so many things in life and here I just see his little stick figures going what do you mean there's no water damage mate you man I would I would pay good money to watch great i under a new board repair I really would like I've never given patreon money before but if grade a under a we're willing to do component-level motherboard repair and deal with some of the stuff that I do I would pay good money I would pay good money to see yeah you know it's interesting lately by the way for those of you that keep asking what it is I'm putting on there that's called flux if you're new to the channel flux helps solder flow this is the flux that I use come on focus on me camera there we go it's trying to focus on my face I figure if I put my face right next to the solder flux you'd be able to see it there we go so this helps solder flow and the thing about this is it also is great for cleaning so the whole idea behind this is gonna clean any any of the junk that's on the board that's going to keep it from making a proper solder joint but also what this is going to do it's also gonna help me in cleaning away that dirt so let's say I take this board and I put it directly in the ultrasonic cleaner let's say there's a little bit of that solder joint that's just barely holding on there's a little bit of junk left the ultrasonic cleaner is gonna wash that away but if I reflow it in a place first then when I go to clean it I'm gonna clean the corrosion off but I'm not gonna up the solder joint so it's just that that's why what I do now is I is I do a bit of a cleaning with with the flux and everything and at first I try to fix the board first an ultrasonic it at the end the reason we were doing ultrasonic in first before was because I had several people working here that did not do board repair that would do whatever they could to make it work again before it got to me so in that workflow with that workflow it made a lot more sense in that scenario to have made a lot more sense within that scenario to have somebody ultrasonic at first but since I'm the one who's both disassembling the machine now and also doing the border pair it makes a lot more sense for me to just go through it like this because I know it's gonna make my life again if it's ultrasonic first I'm not gonna see that there's damage that I'm gonna have to go through and measure every single power rail which means having brain on I don't want to keep my brain on I want to be like you know I want to be like the people that don't use their brain and make money anyway so that's what I'm doing here so just heating away and now I can get a little bit of a better view of what's going on there now remember brain off not gonna look up at any of those things do brain is off baby so I know what the original cause of failure was because one of the things that I got trolled on with that reddit video is you don't if you don't know what the cause is then how are you actually gonna properly fix the problem again for those of you that watch the channel you guys know that I go through and I look for what actually caused it and I explained it in all my videos that are actually longer that was the one video that I did that was short and that's why I don't do short videos in this channel because I don't want to cheat people out of information so but in that video was probably it wasn't liquid to the motherboard the motherboard was in liquid damage but the track that had a little bit of liquid on it and that caused the board to happen but here I already know what the cause was so I know that the issue with the board was something something related to water so the first thing I'm gonna try to do here is I'm gonna try to bring back this see this pad over here people would say that that pad is blown Louis you got to get a pad repair kit why aren't you fixing boards properly with a pad repair kit why because I just fixed it in five seconds BAM magic mofo magic so if I had a guess I would say the actually honestly I don't even know what that is I'm guessing that one of these up here or power is coming into the IC I don't know what that that thing is for you know what I'm not even gonna look it up I'm genuinely not gonna look it up because I don't care we're in brain off mode here brain off mode is great because you get to save because the thing is if I can fix this without using my brain and that means that I get to save my brain for the ones that matter and I've noticed I'm really at a point where I have to save as much of my brain power as I can cuz I'm not finding a replacement to me anytime soon I've been getting more serious over the past month or two about finding a replacement to myself can't do your job forever but man it is hard it is a challenge as I always say great I stole the component I need from this book I'm a thief as I always say the people who can do the type of work that I'm doing here are the people that are employed at the $200,000 or $150,000 a year jobs and the people who will work for the salaries that this business will support they look at the screen they look at what I'm doing and they nod and they nod and they go oh yeah and then I put them in front of something in I put them in front of something in and it's over it's like what and then I cry now I'm not gonna get too crazy about putting them on perfectly because as I have to heat each one to solder it on there I'm going to wind up reflowing the one from right before so I'll be able to flow it in a place just fine so when I go to solder the last one that's when I'm gonna go over all of them and flow them in a place see all I really care about now is getting them down on the board in a manner where they where they stick where they're supposed to it's all about coming up with tactics how can you deal with the things that make you not great at your job makes me not good at my job my soldering is atrocious but doesn't matter I'm gonna make this look like Factory backings it's how you get around your flaws and imperfections that define you it's not the floor the imperfection you think I'm gonna let the fact that my hands don't listen to my brain suck up my ability to do my job you out of here I'm not gonna let my brain win I'll even do it left-handed if I have to and that bottom capacitor could get flowing into place even though it looks right right now I know that it's sitting a little bit high on the right side and you can't see that from this angle in the microscope but you might see it if I tap on it actually it wasn't sitting high that's just me being a freak with the OCD now the middle resistor there on the right side could look a little bit nicer just wait for this thing to beep here this is gonna beep in a second and we go here and bam sexy as hell and still no fan spin you mean I gotta use my brain seriously that's cruel oh well okay it was worth a shot it was worth a shot it was worth it so now I'm just gonna have to open the board view and I'm gonna have to actually think you ruined my day motherboard you got my hopes up okay so this is for the GPU frame buffer power supply which I'm not really that concerned with right now because it doesn't turn on so now we're just gonna go to some basic troubleshooting here which is gonna be troubleshooting power rails and we're going to try to figure out why it doesn't turn on so any time we have a no power issue what I do is I go to the page that has all the power rails listed and we're gonna go from there so which page here is gonna have my power rails listed come on you can do it let's see is this an old enough schematic that it's gonna be listed on page seven this one of those schematics R it's on page 70 that's a perfect page to put the power rails let's put it on page 81 the first thing that you gotta check on the schematic Thank You Apple so the first thing that we have to check here is PP bus g3 hot so on this new board view program if I want to find pp bus g3 hot oh it's beautiful it's beautiful it's so beautiful I love it now keep in mind I know that I have pp 3 before - which is the first rail you're supposed to check I know that I have that because the light is on the charger so I'm gonna do now as I'm going to check for P bus g3 hot you can't see the multimeter because of the camera angle oh well you'll just have to yeah you can barely see it there you go so let me do this I'll get a video and I'll get a video employee by the time you know yeah once I get somebody to actually do this stuff point eight volts 0.8 volts okay so now we've checked the end of the circuit and we have 0.8 volts instead of twelve point six and now I'm gonna check for a short to ground we turn the multimeter to ohms then we go into diode mode and then I pick my red probe put it on grounds and my black probe and put it on PP bus g3 ha and what do you know we have a direct short to ground so what are we gonna do when we have a direct short to ground we have a direct short to ground what I'm gonna do is I'm going to run power into the system and then see if after I run power into the system using my bench power supply if anything gets hot and what gets hot and that's going to tell me what's wrong so I'm gonna get my bench power supply that's sitting behind my HP 65-42 a I'm gonna solder this onto the motherboard right now so I'm just going to do this put a little bit of solder on a screw hole this is the wrong iron to be doing this with since this is a micro pencil but that's micro pencil is really not feeling what I'm trying to do with it micro pencil is not feeling this at all why are you trying to solder a huge ground plane with a little micro pencil oh well you're going to go whether you like it or not I don't need a perfect joint for this it's not like I'm gonna plan on keeping it there then I'm going to solder the nonce I'm gonna solder the positive ends of the power supply onto here now here's one of the things that short detection on pp bus g3 hot is you have to realize the pp bus g3 hot power is the buck converter that makes power for the CPU and GPU which work on something approximately around one volt so the reason that I'm going to start short detection on this line with the very low voltage is if one of the MOSFETs providing the CPU with power is blown if that's the case that if that's what's going on here and I just run power through the board at like five or ten volts because of the 12 volt line and the MOSFET is shorted that means that the power from the MOSFET is going to go directly to the CPU if these MOSFET is shorted and then I send 12 volts to my CPU and my board is and I don't want to do that alright so I got the power supply on and got the amperage set to a high amperage and current is set to one volt and my wires are not even plugged into my power supply great ok so I've put a volt into the board and now I'm gonna try to see what gets hot now the first thing I insure is that the CPU is not even getting remotely warm or the GPU before I up the voltage to do anything else so CPU GPU PCH any of that stuff I want to make sure any of the large chips are not getting hot and once that's the case then I can go a little higher Loren's by a thermal camera Lewis by a thermal camera Lewis by a thermal camera also by a thermal camera when you're not paying like $600 for the resolution of a Game Boy I have just something against getting ripped off I don't have it in me to get ripped off oh yeah fine cool give me 1080p for like 400 bucks and good quality and I'll buy it but again every thermal camera that I've tried so far has been just complete I mean just really like every camera camera that I've tried it's just always the same type of it's some where it's like I see that the board is this big and the yellow dot or the orange dot is this big what good does that do me you know absolutely nothing it's just pointless like I would buy it if it made the job easier it's just man yeah I'm not against the idea of a thermal camera I'm against the idea of spending money on a thermal camera when we're still at this points where thermal cameras are just anyway hmm now here's one thing I want to point out - yeah do you see where here's the thing we wouldn't even need a thermal camera or your eyes would suffice so see this so you just saw her and it's kind of popped out you see what this tells me this here tells me that this had something go onto it even if I wasn't actually running voltage through this particular motherboard so I'm just gonna stop the voltage right now and I'm gonna see what that thing is for but I'm pretty certain that that's our problem so let's just turn on the board view software ah you're seeing my desktop and you're seeing you're seeing my drive and the title of a video that I haven't released the end yeah oh noes and you see the IP address of a backup server I'm going to get hacks or did it hacks or did it hack sword hacks H ax so it's this little mofo q 8760 q 8760 okay so this make this is all coming into play now so the little resistors that died with this one and this stuff here which creates GPU frame buffer now this creates GPU frame buffer from using this MOSFET and if I had a guess I would say that this MOSFET is shorted at least the top section of it at the bottom section because the Geographics chip never actually got hot so that means that maybe the bottom one is short who the know something over here is up and there's a good chance the graphics chip is not dead now this comes from this and this comes from pp bus g3 yacht so this is all making sense now alright this is all making some good sense all right so now here's the thing with buck converters if this is shorted that means that it probably sent 12 volts to this which made this stay on which then caused this to die and this then caused this to die so the whole thing is I have to replace these as a team if I replace this without replacing this this will be dead it will tell this to be on all the time which will then cause this to send too much power to this and they will just die so if you look at my video on why new B socket repairing the CPU v core circuit this will all make sense in context so the whole idea with the buck converter is you have to replace post look at the controller IC and the top and the bottom MOSFET or else you're just torturing yourself so let's go over here and shove this off the board and I'm pretty sure that my short circuit is then going to go away let's just get my air my fume extractor over here get it nice and close bonus if you don't burn the fan connector not burning the fan connector would be a bonus you get extra points for that [Music] okay I'm not about to try and clear MOSFET pads first GPU frame buffer with a micro pencil iron so I'm gonna plug my standard iron in there get my wick in place here wick here which here wikki wikki wikki wikki wikki where are you wick come here wick where'd you go here we go new wick gute wick I think that's Chinese for good this is all these little Chinese symbols on the front of it but it's really good stuff that's why I think G OoT is Chinese for good it's good to know a little bit of the language if you're buying from vendors that sell things in another in another language I'm never gonna forget this is one vendor I don't buy from anymore and I talked about that in a lot another video and there's remember that was unpack I'm packing boxes one time this one guy back when we actually sold parts came by to buy some stuff he looks at the box and he's Chinese and you just laughing his ass off he finally asked him like what the he was so giddy about and he said the box well you're opening a box that's labeled and I thought he was kidding and we opened the box to use the parts and although most of them didn't work so I'm guessing that the guy was right he the guy you know pretty much wrote on the box in Chinese and actually sold us that stuff just one of you one of the things to think about all right so this is not exactly the ideal tip to do this you should use one of those bevel tips if you're gonna do any type of wicking the reason I'm using this is because my beveled tip got destroyed so I have to make do with what I have this is not the ideal tip for what I'm doing but again sometimes and you wanna you wanna you wanna do you want to be the one to tell the customer they gotta wait because a tip got destroyed or do you just want to make do with what you have you figure out how to make do with what you have right and you do your best if not touch the capacitor that's to the right that's what the you're the wick I was just looking for before and you were sitting on my desk this entire time mofo all right so some light sinning what a crowded space anytime you see that Hershey's kiss thing you have to go over your joint again I got a couple of Hershey's kisses there is the angle here is not great it's naturally a angle angle to work with how well it's it's something that's gonna get bashed directly onto the board anyway let's get some flux get my alternate board pray that I haven't stolen that piece yet okay great I haven't stolen that piece yet preheat the board a little bit clean off my tweezer yeah tweezer still has some junk on it and be if you don't preheat the board you can be heating the chip and burning the chip but the board is going to be absorbing the heat if the board is cold you have to saturate the board was heat and then when you go in to remove the chip it's going to come off nice and easy because the board the pads and the board are not cold but if the pads on the board are cold and you're kind of there we go comes off nicely yes I am come and catch me repair police you come and catch me you tube tech police oh yeah I'm doing it Louis I can't believe you don't have every single component for every single motherboard made in the past ten years immediately in stock as a small business how dare you how dare I indeed oh dare I indeed okay there we go it's in a place I move it around a little bit but it's not flat in the board so then once it dries I press on the top now I know I'm not gonna move it around but it's flat in place and I push down and all the excess solder that's on the pad is gonna magically go away a little solder ball that flew away is not getting past me and catching you mofo I can have runaway solder balls inside of my machine and we're just gonna pick up all the stuff that came out the side so it looks nice and clean and pretty and sexy not like that iMac video I uploaded so you know runaway solder balls no runaway solder balls this is such a angle to work with all right is what it is and we go under the bottom of machine we're gonna replace that buck controller I see even if it managed to be good right now it may not be good into the future I don't trust it because I know that a FET in front of it shorted and it was so there's no need if you want a customer to come back immediately the best thing that you can do is half fix their machine Louis I don't want to watch these long videos I don't want to lapse long videos videos and then I release a video that's seven minutes long and then it's all Lewis where's the primary fault they Louis what is the primary fall they Louis you didn't explain everything yeah one thing I realized is you should never try to make people on YouTube happy if you're making youtube videos I would suggest that you make them for yourself and if people enjoy them that's great and if they don't then they don't but if you try to make view Tube videos for other people it's never gonna work you're never gonna make other people happy just make stuff that you that you if you think is cool content and if others don't like it at the very least you can live with the fact that you were true to yourself I will most likely never be a person that does three minute videos just three to five minutes it's not not happening it's not me if you're looking for those videos then let me just tell you now that you're definitely on the wrong Channel I just wouldn't want anybody to waste time on the wrong channel if they don't have to righty that is sexy bunch of pads right there [Music] notice I'm not going nuts to make sure every single one is the same size I just want to make sure there's a decent sized bump I know all of them you know we're going to remove that from the donor board it should be hot enough to come off come on tweezer really is a good wheeze here we go BAM I gotta place this go mother go mofo okay you go to place the guy see heat you know there's no rush I see a lot of people I try to train they're like ah they run on the chip as fast as they can no rush mo no rush man no rush we heat from far away and you see all the flux light but you see all the excess there's a reason for that we're gonna wait for it to flow away and once that excess flows away and you can only see a little ripple amount around every side of the chip I'll show you what I mean by that in a second we're gonna heat it in heated and so you only see this tiny little amount for about one or two millimeters outside the chip so once you can see the puddle of flux is isolated to one or two millimeters outside the chip then that's when I go in close and bam it flows right into place see that now they go far away again I push down on the chip once it's at once the surface tension has put it into place I heat it again I push it down so that it's flat on the board and making a good connection now I'm done and I left a little mark on the outside of the chip but that's totally fine it's probably gonna piss off a couple of engineers but oh well it's part of my fun on this channel you have to piss off engineers will just go over the joins [Music] oh the hands required to do this job I can't wait to find a replacement for myself I'm giddy we'll see how that goes though alright so let's see is my short gone if I inject voltage let's put this power supply at 0.8 volts and I see that it's zero amps are being used so I'm gonna plug this in and let's see if I get a fan to spin [Music] okay I get a light and I get a fan spin you know what just because just because it's a really small chance that 12 volts went to my GPU I'm gonna make sure that it actually gives you a picture on the screen before I get all excited I'm gonna disconnect the power supply [Music] [Music] disconnect the power supply from the board and let's see if I get a picture on the screen again just one of those things when there's a 50-50 chance a 50 percent chance that 12 volts went to the GPU we always test these things but I want to actually just show you on camera because I know there are some people that are gonna go great a under a there are people who are gonna give me the grade a under a what you didn't even check that and you call this a finished repair video take off the air filter what what okay so we're just gonna plug in the bare minimum here so I'm gonna plug in a DC n board I'm going to plug in a screen and I'm going to see if the screen shows me any sign that this thing actually works and if it does then I can clean the flux off reassemble run ASD test in my OS and all that other boring that gets done off camera because that's just it's frankly just boring you you want to see me sit here and reassemble stuff run ASD that's a that's a yawn fest right there that's a total yawn fest so I'm gonna do this plug my DC n board and make sure nothing metal is touching where it should end get you in there okay okay it turns off okay I get a light on the screen and oh well 12 volts to the GPU that's exactly what happened to this thing so I was running something like one volt with my power supply to see what God ha but it doesn't matter because when that FET did what that FET did it sent 12 volts to the GPU frame buffer and so the vram so knowing that all the GPUs I can buy for this board are 50 to $60 in coming from vendors in China that and here's the thing with this like you think most people like Louis well just buy a GPU if I could buy the GPU from Nvidia I buy it but I'm not I'm gonna buy a GPU from some dude that's either ripping it off a dead board or taking it from a spool and here's the thing with that spool here's what I want you to understand is that the spool is where did he get that spool from I spilled my drink on my shirt I just noticed in the camera this is why I can't wear white shirts I can't be trusted with anything normal I wind up spilling crap all over myself the thing is with this is if I could buy that from Nvidia I would be happy to take the time to solder a new one on because it's about a 40 or 50 minute job and I am no fix no pay but wait if Nvidia and AMD do not sell those chipsets the people where do you think that crap comes from it comes from the back of a truck somebody sells the rejects are the ones that were bindas junk so you know have you ever heard of this whole idea of processor binning the whole idea being that you know there's no such thing as a 3.3 or 3.5 and a 4 gigahertz processor they try to make a bunch of 4 gigahertz processors and the ones that fail at 4 gigahertz they test them again at 3.5 or 3.3 and if they pass that then they get released that way what happens is I'm um here's my guess is that a lot of the processors or the graphics chips that won't even work at the normal speeds in some way shape or form of the one that for some reason failed they're binning tests are the ones that get sold and the reason is because I've done enough of them to know they just don't last as long as the original one and a lot of the times they just don't work at all and I was thinking about this and it's like well if they don't sell their good chips to people if nobody can buy them then how are these people getting ah they're buying from the garbage it's just one of those things that would be really cool if it could change in our business but it's not something that I think is gonna change anytime soon but again as this channel gets more popular and as I get to talk about these issues with more and more people and as it gets a bigger audience what I'm hoping happens I'm hoping that enough people realize this stuff but again it is kind of a waste that somebody like me doesn't see it worth the time and replace that chip because all the places I can buy it from our places that will there are places that will probably sell me again good chance I get a chip that works for a little good chance I get a chip that doesn't work at all very low chance that I get a chip that was from the same pile as the one is same bin binning as the one that was originally put on the board so this is where I will call this board repair ended and again the whole thing with the no fix No Fee model the whole thing with the no fix No Fee model I get a lot of easy ones but you know I spent a half hour on this one and I ain't getting paid for it so not much that I can do there not much that I can do at all actually so that's it for today and as always I hope you learned something and support the rights or repair bill so that people like me can buy these chipsets that would be so cool that's it

Channel: Louis Rossmann

Views: 115,623

Rating: 4.8996577 out of 5

Keywords: macbook pro logic board repair

Id: wEwKkhxI73M

Length: 40min 35sec (2435 seconds)

Published: Tue Jun 07 2016

Reddit Comments

[u/gerrywastaken]

Somebody should make a compilation of timestamps for all of his rants. They are always so interesting.