A2141 MacBook Pro no power diagnostic 820-01700 and Some A1466 MacBook Air board repairs

all right so now switching back to our mid-grade tower we are getting about 10 dropped frames and youtube went ahead and sent us a notification saying that we're live so that was actually a lot quicker after switching out the computers yep next second awesome hey we're back haven't been on in almost two months mostly because my main streaming rig went down it looks like i either have a failing processor or my zombies failing power supply i'm sorry or my zombies processor that i bought about 10 years ago is finally on its way out but my uh i think it's a amd 8320 is performing at probably a quarter of what it's normally supposed to operate at so because of that i haven't been able to do any streaming videos in a while went ahead and downgraded back to our old into intel core 2 duo processor streaming rig here and we are actually getting some solid connection here so let's go ahead and jump straight into it it's been a little while since we've done something but i got myself an interesting one here it's a 16 inch 8 21 41 that is just not turning on went ahead and i've already taken the logic board out and what we get when we hook it up to our ammeter is about 20 volts and zero amps just so that we can replicate let's go ahead and turn it on real fast so we're getting about 20 with 0.20 amps 0.3 and then it turns itself off so to me that usually means that something is trying to turn on but it never actually makes its way to complete all the power aliases needed for it to turn on in the past we've seen this be a shorted pp3v3s4 line as well as a corrupted t2 chip so in this case i'm just going to go ahead and look at the power aliases and see if all of our rails are there so let's go ahead and switch over to our board view and see what we got so here we got our flex board view by paul daniels and what we want to look for specifically is going to be our power aliases and this isn't the exact one we want to look for we want to keep going through this page until we find these ldos are necessary for turning on our cd3215s but we're not really concerned about that right now because we do have power this schematic looks a little bit different than what i'm used to working with usb c x support this one is going to be lcd backlight driver which we're not concerned about and this one is usb c t support so this is a little bit different than what we normally used to i see a lot of ldos and these are going to be uh what is that same for limit dropout i think this is going to be what ends up creating our 20 volts on our c3215 so this doesn't look like the normal power aliases of what we've seen in previous schematics so let's take a look at the first page let's go back to page one of and just kind of read through the table of contents see what we have here and in fact actually one second let me pull this up just in case there he is hey how's it going tim i actually had to pull a different computer out from out from the grave essentially in order to get this one working again okay so let's see what we're looking for here we want to look for something to do with power typically it's power aliases power sensors thermal sensors pp bus power supply battery charger pmic ldos it's been a little minute since i've done in a2141 so i can't remember ah here we are there's two separate power alesis pages one on page 1 17 and 118. so let's go ahead and just look for 117 of and that takes us back to usb ct support so maybe this actually is going to be low dropout regulator for dc linear voltage regulator that can regulate the output voltage even when the supply voltage is very close to output voltage that was a mouthful page 1 18 gpu 3.3 volt gpu discharge that's not exactly what the index had told us hmm there we are it was sheet 117 not power elise i'm sorry it was sheets 117 not page 117 sorry it's been kind of a long day all right so first thing we want to check and see is do we even have our pp bus present we should have our pp3b3 present because that's how we have our 20 volts coming from our cd3215 i think this one has cd3215s i don't think they switched them into cd3217s on this model yet i was wrong this one does have c3217s alright so let's take a look over here at these fuses at our pp bus all right so it's going to be about right here specifically our fuses for our pp bus and measuring with our multimeter we are getting 12.61 that sounds about right for this unit oh yeah i'll keep the multimeter down here i did buy a new multimeter from banggood probably about two months that is supposed to have a usb interface and because of the crazy snowstorm that happened in memphis and texas everything's just kind of been a little slowed down right now so it has not arrived yet so we're working with what we got all right let's look at doo doo doo doo sure i'm not missing anything all this looks like this might be related to pee pee bus since it's in the name but this one specifically is also talking about our real-time clock actually not too familiar with that line specifically so let's let's take a look it's still the same voltage as pp bus but let's see what's going on here so it looks like it's going to be down here on the top side of the board same side as the cpu and what kind of voltage do we have on you okay yep still pp bus so that's just a pp bus line let's continue looking forward on our schematics here this is going to be cpu i'm going to take a guess that this isn't present only because we're not drawing it off amperage and it's actually in a very inopportune location let's see if we can take a look at it underneath our microscope camera so we have a couple of capacitors right here and these two right here in the middle is supposed to be your cpu v core and cpu vcore is not present okay so somewhere in between pp bus and cpv core something's not turning on let's now look for our whoops let's put this back up let's now take a look at our 5 volts and our 3 volts let's see this is 1.2 i'm not really interested in this stuff at this moment so this is probably going to be on the next sheet power aliases two here we are so we have our three v3s and our five so let's take a look at our five gs our pp5vg3s i don't know why i couldn't say that that is a lot of different spots on our board let's kind of look back in the same area we were earlier so this right here supposed to be our five volt line we are getting some pulsing let me just make sure that i actually have a stable connection here with my ground my multimeter we have 5 volts and staying at 5 volts so my left hand was just shaking a little bit too much to where it was kind of jumping all over the place that's perfectly fine and what i want to look for is the equivalent of 5vs4 but i don't really see anything like that here and we know that we have our pp3p3 and g3 hotline present because that is how we are turning on our cd3215 we can just confirm that real fast by probing this resistor right next to our battery connector it's kind of tucked all the way over here but i think we can reach that yep 3.3 volts which would make sense because 3.3 volts is necessary oh what is this youtube is not receiving what is this error message i'm getting youtube is not receiving enough video to maintain a smooth stream as such viewers will experience buffering hmm let's see what's going on our network has also been pretty choppy here too uh let's see looks like we're going to have to change something with our bit right here hold on just for one second i will be right back what is going on okay after changing our bit right now we're only dropping about five frames per second let's work with that for the time being back to what we were working on okay so we know that our pp3 v3 g3 hot is present so these look like these are all g3 hot or g3s i don't know if that is g3 sleep standby i'm not sure what the s stands for in this regards so is there any other power aliases that i might be overlooking here let's see what's on our next page next page is signal aliases this isn't going to be anything we're looking for at this particular moment let's just check searching directly on the board view itself so pp5v underscore s yeah see there's an s4 right here but that's going to be going strictly to the usbc so something looks a little bit different than what i'm familiar with i apologize if i'm not as knowledgeable as some other videos don't really work on enough of these 16 inches so let's kind of take a look over here see what's going on with our usbc our pp5es4t usbc that is on the top side of the boards these giant capacitors we don't even need to put this underneath the microscope to take a look at them [Music] let's see what we have here and we have absolutely nothing no short to ground let's see if we get a pulse when we first plug in our usbc ammeter because it does try to pull 0.3 amps before it shut itself off okay so it doesn't look like that signal that signal i wonder because that is connected to our usbc if that's because we are actually hooked up to this specific side of the logic board because whenever we did a search i'm just kind of talking out loud here when we put in pb5 v underscore s4 we can see that there is a t and an x so what happens when we look at our x usbc that is on the other side of the board is that potentially where we have some power right now i'm just kind of going off of experience with previous power just to see if there is any obvious power or missing power so we have c3506 right next to our cd3217s let us go back to our microscope camera and our multimeter says zero and just plugging this in real quick since it is pulsing at first okay this is the part where i wish i had three hands what is your meter reading the meter reading right now says zero however when i first plug in my multimeter it actually got a reading it almost looks like it spiked some power there for a second and then is dropping let's try that again no nothing there still zero okay this is one of those repairs where we actually have to think that's why i wanted to do this specific stream usbc that is oh the usbc ammeter if uh it is reading 20 volts at 0.2 amps for probably about 5 seconds then it goes to 0 amps now from my previous repairs whenever i had that usually meant there was a short somewhere on a main power rail now i know since this one is a t2 chip this one can also have a corrupted t2 chip and going into dfu mode as well let's keep moving is the battery any good oh it's a 16 inch as in it needs the right charger hold on that is a very good question kevin one second let me see if we're even using the right charger because this one does need a battery it is a 96 watt yep aha so that's that is the right charger for this one this one can turn on without a battery though if as long as that's a 96 watt good to see you live again sir good to see you too ipro repair i just haven't really had a working computer lately to be able to do this so that is a good theory we don't have any replacement batteries here for a 16 inch uh last time we got one we actually had to end up getting a used top case which was roughly around i want to say 400 it was uh not really the cheapest right now and there's a lot of really bad aftermarket batteries out there so we're kind of avoiding uh getting any batteries for the 16 inches but this battery unable to really test out at this moment until we can get it to turn on the 96 watt charger is enough for this to still turn on without a battery so let's let's carry on on worth yeah let's see what are we missing here so like previous devices we had different power aliases all on one page this is a power alias as well this is supposed to be a 3.3 volt line for pp5 es4t usbc and no i'm sorry i misread this this is a five volt line right here pp3p3so switch tpt tsn 3.3 volts is supposed to be 3.3 volts okay let's just keep searching on our schematic for this specific one primary ac usb c port controller for upc and that plugs into pp cable usb c port controller ta and it looks like this cd3215 is responsible for eventually making this pp5e s4 line interesting okay so we have a logic gate right here for upct 5v enable r and so we get pp5 underscore our pp5e underscore g3s goes into ub 700 which from my experience is not acd3215 i'm sorry what is this it's on the back side of the device and it looks like this is responsible for eventually creating rs4 line let's take a look at ub700 so we're gonna have to actually flip our board around is this one of the models that won't act without a bmu cable bmu i'm not sure what that is is that going to be the battery cable i'm actually gonna have to do a quick google search on that one tim i'm showing my ignorance here yeah battery management unit flex cable interesting okay so that's going to be the data line cable then for the battery um this one i've been able to turn on without that cable present i had one very specific one i can think of where we were able to let the client use the computer while i was connected plugged into a charger while having that cable removed because that cable was actually the the issue here with that specific client so he was able to continue using the computer without the cable plugged in as long as he had the 96 watt usb c cable plugged in so this is ub 700 this little guy right here that says gas serial so what we want to look for here is just verify that pp5v underscore g3s is going to pin 19 and if we actually have an enable line coming from our upc tvr enable where is pin 19 that is bottom right and pin 15 which is our enable is the fourth from the left on the bottom side turn on our multimeter and make sure that our usbc is actually plugged in so pin 19 is going to be 5 volts that is present now we want to check and see if our enable signal is present it is not present okay let's go a little bit further up the line actually when a rail is not present just for safe measure i like to make sure there's no obvious short to ground and there's not all right so let's go back to our schematic here and see what's going on so upc tv enable r there is a logic gate right here which is ub 740. that is on the bottom side of the board to the naked eye it looks perfectly fine and in order for power it looks like it's going to be a 3.3 volt line coming from our pp3 v3 g3h underscore t we're going to have to have pm rsm reset l and upct 5v enable present all right so where is this to the naked eye looks perfectly fine with the microscope looks even better okay pin six that is bottom right and pin three is top left and what do we have nothing coming there which may be okay because pm rsm reset l l is a low line but nothing at all coming from upc tv enable from pin 3. all right we're going to learn today where does this line come from okay this is going into u1200 which is our hold on it's a little bit of everything platform controller hub real-time clock espi and pm power management i don't believe that's the t2 chip no u3900 should be the t2 chip okay well that's it going into something this is going into something but where is it coming out from probably directly from the cpu and this is probably just a rabbit hole at this point it is coming out of pchpm level shifting okay u4760 does hmm hold on so the signal has to [Music] be low in order for okay hold on let me re look at our logic here the signal here has to be low which i would imagine zero is low enough as well as this enable line has to be present and we have a resistor this is a confusing logic gate because usually a logic gate will not send power to the output until these lines are present this line will not be present from my understanding until sorry sorry let's see where else does this come from ah okay so that is going to be coming out of our digital core i o and controller which is ub 300. ub300 is our looks like a usbc port controller ta is this the equivalent of a thunderbolt port or is it just a cd3217 that's kind of what this looks like here so upct 5v enable that line was not present that line is generated from yeah cd3217 is it possible here our cd3217s are only partially turning on yep here's a coming out of ub400 no we don't want to search ub 300 we know where that's at we want to search for upc tv enable sorry right now i'm actually measuring the resistance to ground on our upct 5v enable and it looked like it was a hundred kiloohm which sounds normal that that's too specific of a mole a reading for that to be something off all right let's switch back over to our oh i still have my microscope camera pulled up so if you are not turning on all the way how is it that you're getting 20 volts but still not sending an enable signal we may actually have to check to see if all of our ldos are present i am going to go to logi.wiki real quick just to do a little bit of research so let's check and see if there's any information about cd 3217 power on sequence for t2 and cd3217 awesome the cd3217 does not have the ldo outputs test the lines for shorts okay bat c3217 can often cause a loop at step 10. needs to be fully function communicate with the system management controller before the cd3215 connected to the charger will request 20 volts we are getting 20 volts though these documents are for specific specific boards but will likely apply to most t2 max okay there are a lot of steps here but that is the power on sequence specifically they said step 10. let's see what we have here okay so we actually need to have a pp1 v8 sleep s2r present before hold on maybe i'm reading this wrong pp3 vg3 hot and then this is turning on our ssd pp3 v3 s5 and what is this specific sequence this isn't for our specific board okay what is it that we are looking at here it's not properly loading so this doesn't look like it's helping it is thinking about it though there we are okay so this is the normal power on sequence pp2v usbc see i didn't see this type of power rail there on this specific computer so this one's probably not going to apply to our 16 inch that we have here eventually makes its way to u7000 which creates our pp bus and eventually turns on the ssd cool did you change the usbc board i'm actually using one that we usually use for board repair but what i want to check out is i have only been using one port so if there is an issue with our cd3217 i am going to go ahead and just try a couple of different ports here and see if we get a different reading all right so we're getting 20 volts here 0.2 and 0.5 or 0.05 i should say and now it's just pulsating i think that was the same thing that we were getting on this bottom port here 20 volts 0.3 and immediately dies to 0.05 all right let's take a look at the other usbc port right here 20 volts is 0.0 20 volt to 0.3 and then 0.05 so it looks like i'm going to get the same reading across the board 0.0 0.2 0.0 that one's only getting up to 0.2 while i think the rest of these we're doing about 0.3 okay let's give this one a visual inspection how about that and let's see behind this specific tape that we have here all right so this is going to be the actual thunderbolt i see and everything looks fine here just the top right here looked a little suspicious like someone else would mess with it you you so far i don't see any obvious signs of damage okay i'd say with the visual inspection nothing too obvious on here so where do we go from here at this point we do know that we are missing that upc line what specific was it the upct 5-volt enable line and we did determine that that line was coming from our cd3217 so if we're missing that specific line i see video starting to get a little bit choppy on my end if we're missing that specific signal let's go back to our cv3217 ah so yeah whenever we were measuring we've got about a hundred kilohms to ground uh that's because we have this rb 2320 or i'm sorry two three two um that is a hundred kilo ohm resistor so that's the right reading so this is going to come out of our cd3217 specifically the spi ace digital core i o control so this needs to turn on first the actual ic whole ic needs to turn on first so what's strange is that it's already getting uh 20 volts so oh man this is where things get confusing because we need that enable line present before we even get power needed to create our pb5eo pp cable so it looks like this talks to a couple different things back and forth until it eventually turns back on thunderbolt tci power enable cio um this is an input this is thunderbolt usb power enable going into it upc power management unit reset [Music] out of curiosity let's check this ldo right here pb3v3 upc t-a-l-d-o that is going to be part of bus power and that is on the bottom side of our board let's turn our multimeter back on and this ldo we are getting 3.3 so that is necessary that is in fact present so we got our ppv bus usb cta that's going to be what powers on our v bus right here that should be present though and there is that pp1 v8 sleeper or sleep s2r that we were talking about earlier that's in a spot that i don't necessarily want to probe okay there we go so that seems to be present ppv bus usb cta or i'm sorry not present the opposite i'm sorry like i said it's been it's been a very long couple of weeks okay no obvious short to ground so where does ppv bus usb cta come from it's probably going to come out of cd3217 later on down the road okay so that is supposed to be a 20 volt line what creates you we know that you go into the cd3217 but where do you come out of it looks like hold on v bus opt opt optimization not sure what that stands for but let's see where else ah okay usb ct connector looks like it is talking on pin 60 of whatever jb 500 is ppv bus usb cta ppv bus usb tb now on previous usbc models i've worked on the ta and tb are actually going to be different ports is that what's going on here what is jb 500 let's just kind of explore this rabbit hole jb 500 is going to be the actual connection where our usbc port plugs into so that's exactly what it looks like here so we might be missing our ppv bus usb c a because if we were plugged into a different port let's simply change that i am so sorry that should not be that loud i apologize to headphone users all right so we plugged into a different port i'm gonna have to get some wd-40 during this stream all right now that we are plugged into a different port let's see what we get as far as that v bus line goes again yep that's exactly what was going on ta is going to stand for this specific usb c or cd3217 and the usb tb is going to be this specific one so we're getting 20 volts here like normal that's perfectly fine red herring now that we know that let's revisit where that is specifically on our ub 300. ub 300 is the specific ce3217 all right and so we were looking for b bus so v bus is just going to be essentially the power for this specific part of it and we're going to have voltage in 3.3 volts uh ldo 3.3 so we probably should make sure that these lines are present too just to make sure it's getting the proper power so let's do just that let's look at vn which is going to be pp3 v3 g3 hot real time clock x i think we checked this one before all the numbers are kind of matching or are blurring together at this point yeah we did measure that earlier so we do have 3.3 volts so that's perfectly normal and let's check our vdd io the pp1 v8 sleep s2r it's going to be cb302 on the bottom of our ub 300 1.8 and that is present vdd config i'm not sure this is anything in particular we're looking for if anything i would imagine this is a signal to change the different vdd voltage and it doesn't necessarily show me anywhere directly on the board view where it's coming from i might regret this later but i'm just going to skip that line and let's go to pp3v3 upctaldo and we've actually already measured that line before and it does have 3.3 volts so we're just going to skip that and pp3 v3 tbtsx 0.003 schematic says that specifically is vlv we have v in lv but we don't have vlv just going to read the resistance to ground on this real fast 34 kilo ohm yeah 34 km hmm that sounds normal but i'm curious as to why that's even missing in the first place we know that v-ret is going to be present because that's part of our pp3 g3 hot rtcx ss super saiyan for you dragon ball z fans not sure what that is i'm going in this completely um completely new open-minded and i've done a couple of these but this one just definitely seems a little different what is our super saiyan line it's nothing ss is nothing looks like it's just connected directly to ground let's check our ldo core the pb1v5upctaldo core it's going to be cb304 cp304 is this specific capacitor and we do have 1.5 all right and v bus opt i feel like this is going to be present i'm not sure if this is in direct correlation to ppv yeah ppv bus usb cta yeah no that that's already present so we actually don't need to check that we're going to go ahead and skip that part p b d c n t a g three hot f not sure what the f stands for in this regards f for free me feedback that's what f's got to stand for all right only reason i say that is because on the actual board view it says fb 200 i don't know if that's a feedback line uh whenever we measured pbdc and ta g3f we are getting 20 volts so that seems about right okay so this part of the power area seems okay except for vlv is this something that we should consider looking into why not i feel like we're going to be on this room for a while so let's go ahead and check our schematic and see where this goes to and it looks like it is 3.3 volt so switch thunderbolt t switch so it takes pb3 v3 g3 t which i knew what the t stand for stood for and it's going to be cmp computer these are our new abbreviations i'm not too familiar with eventually it's going to be make our pp3 v3 so switch dbt which comes from our thunderbolt power enable which is what turns this on i might be getting a little ahead of myself here did we already measure this line before the pp 3v3 g3 hot t we did that line is present what about thunderbolt power enable i might be getting ahead of myself here this is probably something that eventually turns on but not what we're looking for at this moment now i'm not getting anything there from thunderbolt power enabled if i had to guess this is going to be coming from our cd3217 and is going to act as a voltage divider i'm going to assume the cmp is going to be some sort of switch based off different voltages it's going to be doing different things this is all just a guess the only reason i say that is because between our pb3 v3 g3 hot t we have one resistor right here and another resistor now the voltage in between which is pp3 v3 tbt t c and p will change if this turns into ground now this is not ground but i think the cd3217 when it turns on is actually supposed to ground this out which drops the voltage on our cmp from pp3v3 tpt tcmp so that's probably normal what we have going on here we're not getting any voltage and when it's turned off we're not shorted to ground probably because the cd3217 has to actually be on so let's skip this part this is just a red herring let's keep going and this is where it starts getting a little bit complicated because that eventually makes its way to tptt rtd 3 power enable which is part of our poc gpio okay we are definitely going down a rabbit hole here another thing i could do i could cheat only because i've spent a good bit of time here cheating would be you know let's cross our fingers there's a short somewhere like on our if whatever the equivalent of our 5vs4 and 3v3s4 line are on this specific computer if there is a short we would be able to detect it using our thermal camera so we're going to play please bro here for a moment only to see if we can kind of speed up some time gave it a visual inspection and it's perfectly clear so let's see if there is something that is shorted let it open up our software things are probably going to get a little choppy here because this is a little uh processing intensive more than what this intel core 2 duo computer can handle i'm actually struggling just kind of moving this over yep and just like that we are dropping frames so please deal with me for a moment why we kind of resume what's going on here it's just going to be very miserable for a moment looks like it's gonna update about every seven seconds uh let's see so we need to change this to on screen okay i'm so ready to have my streaming computer back you all right nothing on that side of the board that was pretty miserable to watch okay so that's going to be your t2 chip right there and nothing obvious hmm okay so at this point i'm curious if this may be going into dfu mode let's go ahead and get rid of our thermal imager program because i'm curious if ub 300 in order for it to actually send that signal through upc what was it i already forgot the name of it so the five volt the five volt enabled line i'm curious right here for the digital core i o and control in order for it to actually send the upc t5 volt enable line to actually create our pp5 vs4 tnt usbc it says i have to talk to our t2 chip all right this one just keeps getting more and more interesting so what i'm going to do is just briefly reinstall the logic board back into the top case and i'm going to hook it up to one of our controllers that's our computers that is running apple configurator 2 and then we can see if this computer is putting itself into device firmware upgrade mode you mentioned the bmu missing tim and it's not here hold on let me see if one of my texts had removed this that cable is indeed missing okay the only reason i'm confused here is from my previous experience we actually had a client to where his computer just had a really bad battery so the fact that he was able to continue to use the computer with the bmu cable missing and the battery not even being plugged in led me to believe that maybe this one could survive without having that specific cable plugged in because that that was a a case we did probably about two months ago at this point if so i actually don't have a replacement bmu cable in stock for this specific model at this moment at least i don't think so i'll have to double check to see still going to end up hooking up to another computer running apple configurator 2 just to see what exactly uh to see if this is putting itself into dfubode okay do we have all the cables out of the way looks like it's hmm cables never seem to want to go into their home while i'm doing a stream that would be silly if that's all it was this entire time now when this one was brought to us it was already partially taken apart so that that should have been a red herring that probably should have looked round to see if there was anything someone had forgot but the main reason it was taken apart is because it didn't turn on so in these cases it's a little hard to troubleshoot what is the actual issue and what is the client cost issue i think you can recall i had a video or a stream probably about two three months ago i spent i did three streams on it and i finally fixed it actually the last time i fixed it i ended up recording it rather than doing a stream because i kept getting interrupted in the middle of the day i just didn't want it to um didn't want to have a stream of nothingness for a while there um where was i going with that oh but the situation was that i ended up repairing the original issue but then i spent forever fixing the customer-based issue i don't think i have an a2151 in the shop right now i have an a1993 1707s a1708 any 2179 awesome sounds like you got your work cut out for you that's good good job i will be right back i just need to grab another computer here one that has our apple calculator 2 and where did we put that computer here it is of course it would be dead right now not a problem we have chargers you all right so we have to plug our cable from the master port which is going to be i believe the closest port to us on the left side of the computer and then we're going to plug it into any port on another usbc macbook that is running apple configurator 2. all right 20 volts zero amps all right so now we have this computer turned on let's open up apple configurator the trackpad is getting power because i can feel its move hey looking at the schematic i see the battery is one of the essence c4 g3 hot connections now that very well could be the issue that we're having here then tim because if that is connected to the smc line then that could also be why the computer's not properly turning on so this may be a disappointing stream i might not be able to actually fix this one with that missing bmu cable so now the question is do we have one that we can use we are not going into dfu mode over here on our usbc computer let's find out what we have in the system if this doesn't work then i'm just going to go ahead and jump on a macbook air that came in earlier today get something juicy for the stream okay nope does not look like we have any of those in stock all right let's see if we can get one dang i wish i had a 2141 in front of me i've been lucky with a couple of the ones that we've worked in the past usually it's been like an obvious short um or liquid damage and we just replace the individual components but for it just simply not turning on um it looks like we have to address the client issue first okay we can get the ports or the parts we have to address the client issue first before we can actually do the main issue main repair okay so if that is the case uh thanks to optimize logic repair uh here we were able he was able to pinpoint that the battery connection looks like it is also connected to an smc 4g3 oh it's connected to four g3 hot connections hold on let me pull this up myself real quick and so i can take a look and see what you see are you looking at the actual j6950 or j6951 client issue uh what i meant by client issue was that the fact it is missing the bmu cable that uh showed up completely removed now that i'm thinking about it and the bottom case was removed so we're at a point to where sheet52 thanks i'll take a look at it here in a second we're in a situation here to where we need to figure out um what issue has the client cost in this case it looks like because the bmu cable is missing we might not be able to actually progress further to see what is preventing the rest of the computer from turning on let's take a look at sheet52 thank you for taking your time in helping me sheet 52 of of 135 okay let's see what we're looking at here oh whoops yep that's kind of what's going on here okay let's see what we have here our system on chip left speaker audio codec als which is for the camera dfr this is going to be all for touch bar awake connections also for the camera facetime okay if you're referring to this right here let's take a look at u6950 okay the battery actually does have the itc line power clock data hmm because we do have our pp1 v8 slps2r so it is going to be talking to our system management controller calpe and battery charger shouldn't the device still turn on even if the battery is not connected does this have to be present because this is just going to be a data line that going back and forth to the battery i don't know if this necessarily has to be present um i might be wrong in that regards you said try looking at sys detect l okay let's do just that sis underscore detect underscore l that's going to be coming from j6951 yes this is the bmu cable that you're referring to which eventually makes its way passes this um transistor to pp3v3 g3 hot rtcx which we did verify is present this is what i'm thinking sorry wrong connector my bad all right well i actually have my board upside down right now so let's kind of flip the board view around to match what we're looking at being that our bmu's not connected pretty sure we shouldn't get anything that also has the two i2c lines yeah so it is low which i feel was to be ex expected since the battery itself is not actually plugged in nor is the bmu same has battery no the battery does have two um i2c lines you're absolutely right okay i'm just making sure there wasn't anything that was pulling that down and it's not so why just keep thinking maybe this is a red herring is only because whenever we ran into this issue before i know for a fact we didn't have the bmu connected nor the battery and it was still able to turn on as long as we had a 96 watt connector here but i don't know if it could go into dfu mode if that specific cable is missing so we're going to stop right here i'm going to do a little bit more research i'm going to end up ordering a replacement cable at this moment actually we'll just go ahead and we'll kind of get a few of them just in case and let's work on a macbook air get something that actually is going to work or something that we can actually fix how about that before i forget let's go ahead and add this to our cart let's get let's get a few of those why not not today buddy i'm sorry we will fix you some other time imma get some too makes sense all right let's see what else came in today and what bin it's in all right so we got ourselves a macbook air looks like 2013 2014 that is in for just not turning on i actually have recently got a digital power supply since my last couple of streams so let's see if we can get that hooked up here working with our obs cool okay so it looks like it has popped up and let's see it looks like since it is digital we actually have to change everything on the computer i can't set it using the actual power supply directly so we're going to change our voltage here to 18.5 and our current about 4. and let's hit our start button and see if this actually works all right just doing a little bit of troubleshooting real quick just to see if we can actually get our power supply working here uh not today okay well we tried okay we'll just go ahead and get rid of that a new power supply unit what did you get i ended up getting a power supply from circuit specialist it's actually very similar to the one that i used to have except this one does have a usb connection that doesn't want to work right now so we're just going to ignore that for the time being and just continue with the board repair like normal so this macbook is in here because it was just not turning on a second ago i actually just saw a fan spin so let's see what happens when we hook it up to our power supply so we are drawing about 0.6 amps right now and we are getting a fan spin and this is a 3474 i believe which means the computer is going to boot loop a couple of times before it actually turns on so screen just went dark and apple logo why is this one here i can't win tonight i want to do a board repair yeah this one just boot up and booted up just fine we have a charger we have a fan spin and we have we have a wallpaper so i'm not sure why this one is in here this one was quoted by the actual apple store to have had an issue but it's turning on just fine let's pull the logic board out just to make sure that there's no obvious signs of corrosion because why would the apple store deem a perfectly good macbook to have a logic board issue why would we have taken this one in if there and deemed it the logic board issue if it turned on just fine i know we would have been smart enough to actually hooked it up front and test out some general diagnostics just to see why it wasn't turning on in the first place and who took my screwdriver sets missing camera which camera the computer camera or my camera do want to get a better camera though speaking of cameras these logitech cameras they get the job done but they're a little grainy they claim to be 1080p i actually have to scale them down to 720 with this specific computer it just can't handle 1080p stream i can hardly handle 720p stream missing camera on the macbook oh i say cables right here cameras is present and we live in a world nowadays where cameras are very important or no wi-fi wi-fi is right here we got all our cables are you being a bipolar computer you want to work sometimes and other times you don't i've got an a1708 at 5 volts and 3 milliamps worn out usb c ports anything at 30 milliamps is a 30 or 300 milliamps because it sounds to me that maybe just the usbc port is like you said worn out that'd be a nice one we all need a win sometimes there are some repairs that take way too long so replacing the cd3215 and the soldered usb-c port should be fun oh a1708 sorry it just dawned on me yeah that one is not modular aha found it now we know why this one's in here liquid damage around the thunderbolt mux so what probably happened here is the computer wasn't turning on at apple and when it was checked in here it wasn't turning on at all either and by some weird fluke it turned on when we hooked it up to our power supply there we are our cd 3211 thunderbolt port power box so let's just replace this after we look around and make sure there's no other signs of damage what is that only thing is you both know that a1708 has soldered on ports a 1706 has screw on ports exactly maybe it dried out fungus alert yeah this is why we wear gloves we wore gloves way before there was a pandemic it looks like a piece of himalayan sea salt good to see you pedro haven't seen you in a while i think that is a very good idea tim all right everything else looks good let's just work on cleaning this up finally turn on my fume extractor tonight fungus is really good good word here well whatever this is whether it was a resistor or a capacitor it is gone before i hit this though with some flux and kind of calcify the remainder green fungus we'll call it in this case i'm just going to kind of swab this down with some 99 isopropyl alcohol looks like a seahorse boot [Laughter] yes pedro definitely watch some of tim's videos he's smarter than me all right so we're just going to replace the cd3211 as well as these three they look like capacitors so before we actually start heating this area up with our rework going to hit it with some low melt solder by using just our micro knife now that we've touched that up let's go ahead and get our quick rework station and just start heating up the area uh so there goes that capacitor and for all this to kind of heat up this one's definitely going to get a bath because if it has corrosion like this hiding underneath the board i want to make sure there's no corrosion hiding underneath our our backlight driver okay so before we just start swapping over components you can kind of see right here the traces are not really exposed as much so we're going to have to etch into our board with our surgical scalpel just kind of expose some of the copper if the copper is remaining like if we look right here this looks like maybe this was a via that is gone let's give it another swab with some alcohol here yeah so this little component right here is the pads are completely melted away so we need to figure out where it goes to it looks like it is connected on this trace so we may be able to just kind of run a wire between this capacitor in this component as well now this pad looks to be non-existent as well and it looks like it's supposed to connect this capacitor only reason i'm assuming it's a capacitor is this looks like this is all ground and usually capacitors are commonly on ground it could still be a resistor anyways this capacitor is supposed to run right here to this part of our cd3211 so we're gonna have to just kind of run a wire here and i'm curious should i do that now or after i will probably do that afterwards yeah i think that's what we're gonna do this normally happens when anyone ever spills anything through the keyboard this is the part of the board that's actually exposed underneath the keyboard oh no there's a via i don't know if you can see but that but there is a via underneath hiding there yep all right schematic time so this one is an eight two zero thirty four thirty seven it has been a little while since we've actually had to pull up the schematic for an eight two zero thirty four thirty seven so let's go ahead and search our computer for it eight two zero thirty four thirty seven so our thunderbolt 3.3 mux or maybe it's just three volt mux is going to be our u3210 it is a 3.3 volt mux all right so this capacitor is going to be pp3v3 rhv underscore s4 underscore thunderbolt power that is going to be coming all the way from this component so we could do one or two things here we could either try to etch into our via and make a solid connection or we could just run a jumper wire directly from these components the only question i have here is where does that via yeah okay so it looks like the via is going to be going along the underside of the board where all the backlight circuit is for our screen so we could just simply run a jumper wire from our l3200 c3200 directly to our c3211 or we could hatch into the via i think what's going to be a little bit more reliable is if we run a jumper wire it's going to be longer but i trust that versus trying to etch into this via here let's do that on top of that we were also concerned about c3285 exactly what i assumed it is connected directly to c3286 so we will be able to run a jumper wire directly from that as well so this is gonna be fun all right let's switch back over to our microscope camera and decide at this point do we want to go ahead and run our wire now or do we want to go ahead and replace our thunderbolt mux ic i think what we're going to do is run the jumper wire first yeah and i will run the wire from here from our c3200 and just kind of solder directly onto this last little bit of exposed trace cool i actually got a more high powered um uv light from store.rossman group recently and it is made curing mask on jumper wires so much faster than what i've done in the past however since it is more powerful i now have to use special type of uv protective eyes my vision's already not that good it's not 20 20 but i don't want to make it any worse all right so let's connect our wire directly onto this pad this pad specifically is pin 14. all right just go to your channel and copy your url yeah that works too i agree with them all right so let me go ahead and actually switch out my glasses are you on the facebook logic repair group at all i am i don't really post on there that often i'm more on the rostman discord than actually on the um facebook group i post there probably about three weeks ago when i discovered that you can replace the wi-fi ic on an a1708 but you also have to replace the wi-fi rom and the bluetooth rom and that's so far been the only thing i posted i'm kind of a lurker in that regards i know that joe joseph hughes he's on there a lot so it's tim tim posts a good bit other tim tim herman all right don't look at the light paired yes the wi-fi rom and bluetooth rom are paired or married to the actual wi-fi ic i discovered tcrs is the man tim's very smart he's a very very smart individual especially for how young he is i have an employee who's 17 and he's pretty smart as well it's just amazing how much smarter kids are well i shouldn't say kids i should say how much smarter uh just people are in general when they have access to more knowledge i make myself sound like an old an old man i'm sorry guys it's been a long week that was uncalled for we hired someone new this week pretty excited to bring them on board so now we have four technicians working here this will allow me to spend more time doing board repair while they can kind of take care of the general diagnostics and ssd upgrades on imax beautiful okay and let's try to bend it a little bit more right here all right my hand's only shaking because i'm trying to squeeze this at the same time while trying to actually put it on our wire here there we are but yeah this laser is definitely a game changer compared to what we had before we kind of had more of like a detective light so the kind that you'd use on a crime scene it covered more of a larger surface while this is definitely more acute more uh accurate or i guess you could say precision like the other light we have you definitely don't want to take to a motel and you're going to see some things that you don't want to see but this type of light is really good for curing just carrying a lot of things i wonder how it would work with nail techs all right so this is going to be our l3200 and our c3200 and just to make sure we basically just want to be soldered we probably actually solder ourselves directly to sofia here or not b it's a test point let's take a look back at our screen and see so right here that is yep on this test point so that's exactly what we're gonna do let's go back get our what am i grabbing grabbing some flux how about that kind of a dab of flux right here and let's also grab our solder so that we can tin the area up and now we're just going to push our wire down into this pad beautiful another thing with these uv protective glasses it's kind of like putting the world into night time mode day shift mode night shift mode not day shifts everything is orange completely filters uv and blue light everything's orange kind of comfortable flex board view for the win good for you supporting paul daniels and fellow aussie are you from australia that's pretty cool yeah if it wasn't for both pierre enough and paul we wouldn't be able to do our work as efficient that i am very grateful all right i don't need these glasses anymore switch back to my actual prescription glasses now that we have that wire there i think we are ready to go ahead and replace our cd3211 let me just kind of put a pad or a mound on here that's cool piernov is amazing too he is he is smarter than i could ever hope to be all right so we have this area prepped now let's go ahead and take some donor parts from another macbook we have here let's search for a donor so this one is a 820-3437 and i got plenty of zero zero one six fives they basically use the same parts but i like to just pull one from the exact same board perfect found one right here this one just looks on the dusty side so let's go ahead and run some solder along the pins to make it melt a little easier for us so so well thank you pedro i appreciate that i don't really have too much to talk about though not quite like a let's player i can famously talk about like food or comedy at least not this week like i said we've had a very very busy week i'd like to stream more but since my main streaming rig went down about two months ago it's been a lot harder and um we've just been short staffed which is why we ended up having to hire another technician here very very happy with her and um now that she is here she can help out the other technicians so we can get more local customers taken care of so i can focus more on board repair and streams because i thoroughly enjoy doing it stock market advice i don't know the first thing about stock market when everything went down with gamestop and amc all my adult friends will call them uh just because they're probably better at handling that kind of stuff than i am uh love talking about but i had no arguments i just i'm very ill informed it's just kind of the way that i grew up i was always taught not to invest in stocks nor have a credit card i'm now learning as an adult that that is not the way to live life anymore female tech yes actually i have three female techs here technically actually have outside of me there's five other than me there is four technicians if you include me then it's five there is one tech who is a high schooler he's the president of the robotics team part of student council and taking college classes he he's he's definitely something else he is very smart then i have my wife who's been working with me for five years she is a very very smart technician my sister works here she is an esthetician so she just kind of naturally has attention to detail makes her a great technician catches up on some small attention to detail things that most people wouldn't catch and then we ended up just hiring another female who has five years of experience working at franchise repair shops as a manager and i can tell that she loves i can tell that she's already enjoying the mom and pop aspect more than the corporate franchise that she used to work for before so it does not matter what gender you are as long as you have a brain because that is all this job is is deductive reasoning south carolina that is correct i am in upstate south carolina about a 20 to 40 minute drive away from north carolina all right so we got our u3211 on there let's go ahead and get our replacement capacitors all right this time i'm going to end up using my micro tweezers so let me go ahead and switch it out all right so we're going to cheat with this capacitor because we're going to heat up the ground area with our rework station while heating it up also with our tweezers it's going to allow us to pull it off the board a little faster okay um tim if you have yourself an office in your house honestly i think for starting up reasons that is the smartest thing to do especially with board repair with a storefront everyone is just going to assume that you do iphone screen repair you have to brand yourself very well and if you're getting work in mail-in i think you're doing a very good job and also keeping your your overhead low during these times there's nothing wrong with that all right so we will go back and touch this up in a minute just kind of loosely letting that capacitor fit there sit there and then i'm just going to kind of heat it up with my reflow station yeah that's what every one of my customers tells me you're lucky you work from home during these times i think that's a very a very privileged thing um privilege is probably the wrong word that that word is not what it means 10 years ago it's just a nice luxury all right now we're just going to grab this tiny little capacitor here and after that we're going to be able to just kind of toast our board up a little bit melts all the components onto ground this all right so everything's kind of in place now to make it look pretty now that our board is kind of hot from where we last probed it or heated it up with a rework station we should be able to time kind of touch this up with some solder and our micro tweezers all right now let's kind of heat up the area one more time just to make the all of this smooth oh no no don't blow away a little capacitor okay i think we can work with that now last thing we have to do is just kind of run a little jumper wire from this end of the capacitor to this end so for that i'm going to switch back to my micro pencil okay and just to make sure that's got a nice solid connection because this isn't pretty but it's gonna work now we're gonna put a little ball of solder right there cool that should work my videos are not structured while i am flattered i kind of just roll with the punches i appreciate it i tried making a lot of uh uploaded videos that i would actually edit using final cut but what happened is it just took me too long to edit and then actually upload when i go home i have to take care of other things for the shop or update our website just haven't had really the luxury to do that as much so streaming seems to be a little bit more efficient for me okay and let's just kind of touch up this side of this capacitor one more time just to make sure it's properly touching the wire we made and it is i think that's going to be good enough for everything that we need so that's kind of just uh put this loosely back together and check and see if we have a working thunderbolt so this one uh this one did not want to work on this one is now a donor board for obvious reasons but it looks like it saved this macbook here let's put our donor board away thank you for helping us today and where is the rest of our computer what bin did we put this in [Music] um all right it's this one we actually have a couple of macbook airs i just had to figure out which one we were actually working on all right so now we need our t5 screwdriver just to kind of loosely put everything back in we're not going to fully install it because we do need to still give this one an ultrasonic cleaning afterwards let's see it's 11 41 streams been going on for about two hours and 10 minutes and that's because a good an hour and a half was probably dedicated to trying to troubleshoot that 16 inch we might actually go ahead and take care of a backlight for another macbook air we have here just to kind of get some more progress and we're starting to pick up liquid damage season here i have another macbook that has a lot of components that need to be replaced turns on just runs slow every now and then shuts off a lot of components around the smc are not in the healthiest condition so that's another one i gotta work on okay and what we're gonna do just so we don't actually see any client data is we are going to boot into a test drive that's just an external solid state drive that has different operating systems on it very very handy tool to have i i have not had an ipad pro port job or ipad charge port in a month now that's good unless you you enjoy doing those then then i guess it would be bad i actually have a couple here that we need to do um yeah i'm actually looking we have a macbook air charge board over here and recently i actually had two macbook pro or ipad pro 11 inches that both came in with the usb c port just completely charred almost looked like maybe there was a moisture inside the cable they plugged into the charger and killed it but it's just weird that happened to two of the same devices two different clients around the same time okay so here we have our test drive and we have different installations of mac os it must not be ipad chargeboard season it is keyboard replacement have you by chance had any success replacing the keyboard on a riveted let's say usbc model the rivets are a little different so i have not had success i've had success on the older retina models what is that brick this is an external enclosure with a 2.5 gigabyte crucial drive this has different installations of mac os as well as installers nice website you have thank you i've spent way too much time have neglected my wife on too many nights working on that site admittedly i've not updated anything in probably three months i do need to finish taking care of that but i appreciate you noticing uh yes like a1708 keyboards have you ever replaced the key on there because the rivets they're they're weird they're it's not just like a standard rivet that goes straight down it's almost um curved in the center so it's very easy to rip off half of the rivet okay so the computer is now turning on that's exactly what we want but what we want to do is now plug into our usb or i'm sorry not usb our thunderbolt port i'm too used to saying usb on the thunderbolt on the other ones so what we're going to do is hook up to this television here and i need a thunderbolt or mini display port to hdmi adapter let's see if we fix this one all right it's detecting hdmi 2 and let's rotate the camera here haha alright so we have a fully working thunderbolt port on our macbook air so we're going to go ahead and unplug that so that was a successful repair um it looks like the computer just wasn't turning on probably because the amount of crud that was on there so we ended up replacing the uh cd3211 as well as running a jumper wire on a trace that was completely missing um which fixed the thunderbolt issue as well as fix the computer from not turning on uh and now thunderbolt is working computer's turning on gotta finish doing a qc we'll give this one an ultrasonic cleaning probably in the morning because i want to work on another board so that was a successful board repair let's go ahead and work on another one we have here sims says yep what i do is after popping out the whole rivet i take a nine millimeter drill bit and drill holes out except for one millimeter keyboard like what you would do for an air a bit tedious but it works and you all will have to pardon me for all right apologize for that it's just the wife checking in on me okay so this one has a backlight issue so i'm just going to replicate it confirm that there is indeed a backlight issue so let's switch over to our overhead camera okay things are kind of just hanging here so that's why i'm being a little cautious and let's give it some power and we're pulling 0.03 amps interesting let's end up pulling the board out see what is going on here um hopefully i didn't just do anything by having the wi-fi antennas up against the smc let's try this again with that being removed still at 0.03 and now we're no longer getting a green light no there's our green light 0.03 got our amber light and still just kind of staying there so let me check notes on this one real quick just to see what is actually going on with this one okay found [Music] lots of liquid backlight circuit has lots of liquid damage let's take a look at that i'm sorry i've actually missed everything in chat um this computer is pulling 0.3 amps so i'm just kind of checking the notes real fast note said that there was actually a substantial amount of liquid damage around the backlight circuit which i would agree there is a good bit right there although that shouldn't have anything to do with the computer not taking any power so i'm just checking to see since it was liquid damaged uh if there's any other signs of liquid damage on here um it looks like it's all just around that look on this side nothing too obvious over here okay sorry not 300 milliamps um 0.33 milliamps i know 300 milliamps usually is uh scary usually in my experience that's a dead cpu so what we're going to do is just we're going to remove this junk and then just try to get another reading from there kind of attack the obvious now uh 300 milliamps is usually a very depressing number i get i try to avoid that number as much as possible it's every time it's a dead cpu alrighty let's go ahead and start removing so this is tim's group or question mark i'm not sure what that mean what that means sorry plural or verb i don't know i'm in tim's group but not martin or dustin's do different technicians have different groups i'm actually unaware of this yep there's a lot of crap underneath there now let's go ahead and clean this up so since this is a ball grid of array what i like to do is just take a little bit of wick and wick up all those solder pads using the rework station instead of an actual iron i'd say that looks a lot better so let's give the computer a second to cool down and kind of catch up on some things let's see i actually need to move this window over to a different side because i can't really see any comments because my microscope is in the way what's going on here um okay stuff i don't really want to poke okay this has had some time to cool down let's check and see if now we get any change in our amperage consumption you have a celebrity in your stream i do i actually have not been able paying attention to chad recently so if you're in there hello all right still pulling 0.03 so what are we missing here let's go ahead and start with our power aliases usually when it's that low from my experience that is usually a um no that's not quite missing pm sleep s4 pm sleep is usually around like 15 to 20. yeah i don't disagree is loose here i don't know if so i'm sure i'm making an ass of myself pedro is a celebrity here all right so let's go over and switch over on to our schematics here and just simply start with our power aliases and find out what is or isn't present so that is going to be on what page page 100 or sheet 62 so first thing i'd like to look at for is pp bus g3 hot that's just kind of the way that i operate it's okay we're just talking about you oh thank you okay let's see hopefully it was nothing bad okay so let's go ahead and turn on our overhead camera we're going to measure this this um why can't i think right now um fuse to check and see if we are getting pb bus 8.6 pp bus is in fact present dead cpu you shut your mouth 0.03 at 33 milliamps not 300 milliamps we are not going to talk about that yet okay back on to our that's right i shifted things here in my obs so things are a little off let's check out to see if we have pp3v42 g3 hot and that's usually around this part of the board present okay do we have real time clock let's flip it over and check it that out it should be a little bit easier if we look underneath the microscope for this one pch transplant i really wait nope you have green light pp3v43 present yes you're not wrong sorry i'm just kind of in the motions right now just reading um different things but you're not wrong it does make sense all righty here is our clock bp3p42 i don't know sometimes the light on this um well now never mind never mind i was about to say something stupid okay 3.3 on clock that is present pp5 es5 that's measured right here next to you 7400 you're doing great thanks pedro 5 volts let's look at pp5 es4 rs3 oh sorry i didn't switch my screen over so we're going to be looking around u7600 right now that's about right here definitely a lot of dust in this area not present make sure that it's not shorted nope perfectly fine spi not looking too hot the spi is mostly dusty it looks like corrosion but it's mostly dust we'll actually just go ahead and give it a quick little wipe down this is just a really dusty board um there's a couple of parts on here i thought were corrosion although there was definitely something a little sticky right there that looked so spec oh it was sticky because of the flux that's on our work mat okay so we're not going into an s4 state and we are not shorted so now let's check and see pp3p 3s5 should be present because we did get that on our clock yeah just because we're already here might as well okay 3.3 how's you 5000 i was just about to check that because if we're not going into an s4 state field like the 5.5 oh wait you 5000 my bad that is going to be the smc i'll take a look at that here in one second still really dusty in this area too don't really see any signs of corrosion okay pp3v3s4 is not present cool so just confirming the device is not going into an s4 state which means we're probably missing pm sleep s4l jtag is fine i did look at that earlier and it did look perfectly fine all right enjoyed watching your work thank you the time to go solder my own stuff stay safe good luck and thank you as well and i hope it's not a pm sleep s4 drama that might be what's going on here okay uh what i was doing real quick is just kind of measuring make sure that nothing over here was grounded that could have been pulling something down only because we did have a lot of corrosion in this area didn't know if maybe had time to oxidize and therefore actually damage a capacitor so nothing was wrong there that was going to be my next step tim let's check and see if pm sleep is for plus present solder balls that is okay so since you already beat me to it we're going to do pm sleep sleep spell sleep properly s4 l and let's see where you're located all right let's see what we have right here pm sleep s4 is missing okay so something seems to be going on here let's take a look at the solder balls underneath the smc and doesn't look like there's necessarily any corrosion over on that side look fine here okay so normally whenever we have an issue with our pm sleep s4l it's going to be an issue either with the spi the smc the bios or the clock so i'm just kind of looking around the areas here and just kind of cleaning this area up of dust so we can get a little bit better of a look all right so let's find out if the smc is even getting power hear me check signals on u5110 smc reset up one second u5110 let's check and see if smc reset l is present coming from pin five it's going to be our bottom right part pardon me for a moment the attachment i have for my power supply is just not long enough so i'm actually switching up my cable right now there we go we got a little bit more breathing room okay so let's switch back over and the device is turning on i think you have a bad cable this was the cable i was using uh this is this is a cable that i actually got from paul stream um and you can see that it's like a standard 12 volt dc connection the other side is going to be your magsafe 2. so i just switched it back to an oem adapter and it's booting up yeah looks like i was getting trolled by my own equipment here not using that one anymore back on to the original repair this one's in for backlight repair did you say it's powering on yes triggered indeed all right so if you use a power supply i recommend using an oem apple charger just slicing off the tip of it and plugging the outer metal shielding to ground and the inner insulated cable to power that tend to resolve our issue here because our issue ultimately was our charger you know come to think of it we actually had a client never mind i just had an epiphany we had a client drop off it was actually that thunderbolt that we just worked on earlier where it wasn't turning on with our power supply we were using that adapter we were getting 0.33 milliamps and so we thought it was an essentially uh pm sleep s4l but it actually turns out that the thunderbolt was bad given the amount of corrosion preventing the device from turning on so we were getting trolled here again with that cable and um it actually turned on with oem so i don't recommend using that adapter i don't even think i have the uh packaging for it anymore but it was something that we ended up trying from a stream that we saw before and that's what i get for trying to try new tools back onto the backlight circuit repair let's replace that backlight okay so we already have our area prepped we just need to actually put um some more flux over here that was actually a little bit too much yes exactly the one that i just worked on earlier was trolling us because i remember i do recall a tech talking to us or talking to me saying that was only pulling that much ultimately it still needed a board repair because when the client brought it in it still wasn't turning on but that entire time it looked like we had been trolled by our cable okay so we need a replacement driver where are they there they are lp 8550tl e looks like we've used a good bit of these so we may have to end up ordering some more soon okay so now that i have it out just to give me a quick refresher let's look at the orientation of this specific driver looks like pin one is going to be facing in our bottom left so our dot is going to be facing in the bottom left as well change back over to our microscope camera and let's get our driver lined up and prepped to be reflowed back into place reworked back into place reflow has such negative connotation now so whenever you're doing something like a bga rework you want to have your air output and just a lower um i guess output throughput if you blow too hard the chip will go into your fume extractor and into the ether you want to know how i know so if you use the quick 861dw um i have mine set to 50 or 60 when doing bga rework but whenever i'm in the process of just moving the bga off i use more around 80 to 90 for the output it does take a little bit longer but it is going to prevent the chip from blowing away it's thinking about it i'm waiting for it to dance into place let's turn up the output just a little bit more and just kind of tapping it to wiggle it so that's good now let's let that cool off for a minute um it's still a little bit too hot so we'll let that continue to chill this may be my last board repair for the stream and if so then i do have a couple more boards but i like listening to music don't have my bluetooth headphones and if i were to play anything um probably have a copyright takedown right now no data what's going on excellent connection okay so um yeah i will probably do a uh put the board back together make sure that the display actually comes on and after that just uh kind of turn on some jams and finish up the rest of the night taking care of that stuff but let's see where we stand with this one the sad thing with this repair is it's not the first time that i've had something equipment wise troll me and i find this to be a problem whenever um and now that i'm a board level technician is whenever something comes in not turning on my mind goes into the most convoluted fixes now this device isn't turning on probably because of this we're gonna have to look into the power rail and no just the power button doesn't work so um that's where my wife kind of humbles me and um makes me kind of take things back onto step one of diagnosing because it's very easy to get off track and go down rabbit holes looking at the wrong thing when in this case i just had a really bad uh non oem charger that was preventing this computer from turning on so never forget the essentials never start with you never skip your basics always always start with step one don't perform brain surgery on someone when all they have is just a cough all right let's grab their fan i'm gonna make a video of me trying to replace the usbc port on the a1708 and cd 3215. i bet you can't count more than five texts and i have videos doing the repair i know lewis has done one i bet you can't count more than five texts that the video is doing that repair oh okay yeah i understand what you mean now yeah uh definitely lewis has done a lot of uh repairs on that i think jessa did a video uh in warp from rossmann discord uh also uh known as alexi he has done a video recently i think chris from shiny computers did one i don't think i've necessarily did a video titled cd 3215 replacement but i know i've done one in a live stream to do a repair um so you need you need to add your name onto the list get up there call it something um clickbaity like one trick apple doesn't want you to know uh you'll get so many so many clicks that way one simple solution the genius bar hates you can replace these non-replaceable parts there you go i like that okay let's check and see if we have backlight um looks like the battery is dead so we're gonna have to hook it up to our oem working apple magsafe2 charger we have a fan spin so let's option boot for this one all right we got a working backlight let's boot into the in os just to show that brightness control is working all you need is a hot air station a soldering station a microscope and your brain or if it was a buzzfeed video how to fix your macbook in nine easy steps step one take it to tim at optimize logic repair this screen almost looks like it has appealing layer which is strange because macbook airs don't have that it's just really uh oily oh that's exactly what that is it's just like oil essentially so this one's gonna need to be cleaned up too looks like it's almost like um you know how things in your kitchen get oily from like cooking at least i don't know if that's a southern thing here uh here but we get that with like fried foods um people just cooking fried food all the time looks like track pads not responding but the keyboard's working shares the same cable but yeah uh how people deep fry and it just kind of leaves like an oily residue on like your microwave and things like that that's kind of what's on the screen here is this feels like this was in a kitchen even looks like there's oil so this is probably a macbook people use recipes for okay so the spi mode of the trackpad is working but the usb mode wasn't so if i had to guess there actually is a tiny little kink right here i probably don't have the cable in all the way um but the track pad or the keyboard at least was working in usb mode it looks like it's working spi mode and then last thing we want to do is just make sure that the actual brightness control is working so we did this all the way down all the way up and that is a successful backlight repair we'd only been trolled because of this wrong cable that we had earlier um really really disappointed in that cable it just added an extra 30 minutes into my time here that could have been spent elsewhere but you live and you learn we're going to move on from here so that's a successful board repair i'm going to go ahead and end the stream here just so i can actually play some music without getting flagged and having my video completely muted from youtube so that is a evening thank you so much for joining me tonight um wish we could have made some more progress with the 16 inch i'll see if we can try to do a little bit more of a stream when the bmu cable actually comes in from there um but until then i plan to do a couple more of these one now that i have a somewhat decent streaming computer until we can actually build the actual computer again so um yeah without all to do thank you again and have a wonderful evening bye

Channel: iRevive

Views: 1,852

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Id: srQevCSgyFQ

Length: 179min 20sec (10760 seconds)

Published: Tue Mar 02 2021