hello and welcome to another video in this video we are going to continue with the class that what happened when you guys receive an iPhone that is no power okay so welcome to my channel remember my name is Edgar and I'm micro soldering technician with almost 15 years of experience and I'm preparing this kind of boards science maybe 10 years 8 years I already have a YouTube channel and Spanish okay with there I teach so many people this kind of repair I also travel to another countries to have these classes okay in this video I'm going to try to teach you I always say try because my English is a little bit bad okay and thanks for all your comments I always read your comments and I'm going to try to explain you which ones are the next steps when we receive an iPhone that is no power okay we already did a video the first video you can check this video and this video we talk about the principal lines okay we talk about the principal lines okay remember we have iPhone 7 and up we have three different line three principal line we have one that we are going to call this line but okay we have another one that we are going to call this is in Maine and this is boost BDD BDD main and BDD boost okay I told you in this line you had to have around 250 to 350 millivolts and dial mode and you had to have the voltage of your power supply for example 4 voltage and remember I did this draw right here we have a connector a FPC battery connector right when we connect our power supply we have the first line but okay cc bat and then this line come to one circuit tigris and some models we have a mosfet iphone x and app don't have any more the mosfet you remember that okay so we have a mosfet and when the bat come to tiger tigris so here is going to burn another line this line we know this line for bdd main right and then this bdd main have so many components on on these lines and we have another component that is ic boost and here we have our third line bdd boost so this is the principal lines right and remember when you just connect the battery a lot of components are um have four voltage and the amps the ones you put on your power supply okay I told you what happened if you have some consumption of when you just connect your power supply what I had to do so that's why you had to check the first video okay now we have to understand that we have another big component right here that we are going to call this one PMU when we connect the battery and the principal lines are alive so these lines are going to come here to this component the PMU we are going to have this line principal lines because this PMU are going to have the principal lines to provide the secondary lines the box and the LDLs I'm going to explain this to you and in another video okay so right now the PMU is off because remember to have the PMU working you have to press the power button so right now the PMU is just off ok but before we check the second stage of power on we still have to check two measurements that are so important to check when you have an iPhone that is not power on any model is the same thing ok so I'm going to do another draw right here so we have our PMU and we have the principal lines principal lines when the PMU receive the principal line so the PMU are going to start working in some mode for example standby mode something like that so the PMU the first thing are going to provide One line, one point. 1.8 voltage or 1.7 voltage to our power connector this is our power key or power button okay so we have to have 1.8 in our power connector and the second component is the PMU are going to start working with one oscillator 32 kilohertz okay 32 kilohertz okay so we have to we still have to check these two steps before we press our power button okay the first thing is 1.8 voltage okay I have right here an iPhone 11 Pro this if you can see don't have NAND you also can check these measurements without the CPU we just need the power supply the connector the battery and the PMU that's it okay so remember you have to check where is the power button and the models are you checking right right now I have an iPhone 11 Pro and I have a 12 Pro okay I'm going to check on this and I'm going to do the example in these two model boards okay so right now I'm going to come here iPhone 11 Pro okay 11 Pro and I always put this name power no I am I put bottom, bottom side, okay? Right here. We can see this line in some models, power key, power button, or side button, okay? You can check which model are you fixing because you have to check this name of the line, okay?
So right now, I'm going to come back right here. And the Jota CR tells me right here is the power button, the power key button, okay? So I'm going to check. this power key button okay I'm going to come right here I'm just going to bring my power supply and I'm just going to connect the power supply I'm not going to press anything and I'm going to grab my microscope and I'm going to check this voltage okay so I'm going to check this voltage right here right here, see?
I'm going to put a multimeter and I'm going to check right here see how much I have? 1.5 almost 1.7 and remember this models you can have 1.2 1.5 1.6 1.7 or 1.8 it's good okay but sometimes you are going to have 300 millivolts 500 millivolts that are as but that voltage are bad or sometimes you can have 2.5 3 voltage that voltage are bad too i'm going to teach you uh which component is the is the the one provide this voltage okay so right now we check this one and we have 1.5 and if we check from where this voltage is coming you can see this is we have a diode right here and then we have a resistor and then this line comes all the way down to our PMU so the PMU is the one that provides the 1.8 voltage this one so sometimes if you don't have this voltage it's because, listen it's because it can be a problem with the PMU or it can be a problem with the oscillator I'm going to teach you how to check the oscillator later but right now we have this one sometimes you can have 2.5 voltage or you can have 3 voltage this is bad we need at least 1.2 voltage all the way to 1.8 voltage okay so the PMU is the one are providing this voltage okay I'm going to I'm going to check another model right here I have iPhone 12 okay iPhone 12 okay I connect my power supply I'm going to come here and I'm going to open iPhone 12 Pro this is an app 12 enter and 12 is the same thing I'm going to put here bottom and it's the side button see this line is telling you see the name of this line yo bottom side L I'm going to teach you what it is L 1.8 voltage and we have right here the 1.8 voltage so to come with my microscope I don't press anything and I'm going to check and I'm going to check this okay right here I'm going to put my multimeter and I'm going to check this one so I have in this one 1.7 okay this is so important to check sometimes okay for example sometimes you don't have 1.7 you have three voltage if you have three voltage you have a PMU back so you have to replace the PMU I always say to my students the PMU is is one component that you have to be careful when you touch this component okay so i only touch or remove or change this component in these three cases when i have a bad 1.8 voltage in the connector i have three voltage or i don't have anything when the pmu is getting hot when i just connect the power supply or when i have a bad secondary line okay that's it and uh if we come back right here and we check this uh power button and this one is coming from this filter and then we can see that is coming from the PMU that's it okay so when we have an iPhone that is not power on I always check the principal lines and then I check the power button key always always always okay and then we have to check one oscillator oscillator okay because sometimes if we don't have this oscillator good the power the PMU is not going to work good okay to check the oscillator it's better to have an oscilloscope but don't worry if you don't have oscilloscope because the oscillator is one component that don't have so many problems I maybe I just replace two oscillators in 10 years the first thing that you always have to check in one oscillator is using spectrum visual inspection just to check if it's not like bad in bad direction or if it's damaged broken or something like that because some people don't understand a lot this kind of repair they just remove and put another one or they apply too much heat and they move the oscillator to another direction so you have you always have to check the oscillator I'm going to show you how to check it in iPhone 11 Pro but it's the same thing in all the models okay So I'm going to come back here and I'm going to open iPhone 11 Pro, right? So I'm going to come to my PMU.
The PMU have so many pages, okay? I'm going to open the PMU page. Come on, come on. I'm going to search for the PMU. Okay, here's the PMU.
Okay, the PMU have four pages. Always in the last pages. is the control of the PMU okay here is the control and we always going to have one oscillator right here see this one is 32.768 kilohertz and if we check this oscillator is right here so I'm going to come with my microscope and I'm going to show you where is this oscillator okay so it's right here okay right here right there okay so you always had to just see if is any damage with your microscope and that's it if you don't have an oscilloscope don't worry you can check some range of voltage sometimes you are going to have 600 millivolts okay so this one is telling you maybe you have some signal there maybe but you are not seeing the 32 kilohertz okay but like I told you don't worry about this oscillator because we don't have so many problems with this component so I'm going to connect my power supply I'm just going to connect my power supply to this phone that's it and I'm going to see I just connect my power supply and I'm going to check this oscillator with with my multimeter okay so I'm going to come right here and if we come back right here we have two lines this one and this one and we have two capacitors I always check this capacitor in this way I just...
where is the oscillator? it's right here, see? I just check it like that I'm going to put my multimeter in the screen and I'm going to check like this I'm going to check this one first see this one has 200 millivolts and I'm going to check the another one and this one maybe I'm going to have sometimes I have right here 700 millivolts check like that see 400 400 sometimes we have more like I told you this one is don't tell you the oscillator is good we just use this one just to check okay but this is not good measurement okay see 200 sometimes we have 700 right there, ok? the best way to check this oscillator is with an oscilloscope but don't worry, if we still have tools to buy don't buy directly an oscilloscope because you still need maybe a NAND programmer before the oscilloscope so I have the oscilloscope right here, I use this one I'm going to reset this one, I'm going to come to storage and I'm going to click the default because I use this one sometimes so I always have to do this one before I start checking another line so to use this one I just have the proof I have the proven 10x and then I'm going to put ground and I'm going to come right here okay this one and I'm going to put my proof in this capacitor right here okay let me just... I think I have...
right here okay I have something right here so I'm going to put it like this see? right here I'm going to put it right here and right now right there okay right there I have a signal I'm going to press here frequency I have here the frequency I'm going to click this one I stop okay and I'm going to come here measurements and so sorry I'm going to go measurements, font size and I'm going to put extra large ok see 32 kilohertz ok 32 kilohertz that means my oscillator is good just to understand this if you have an oscillator working you're always going to have 1.8 voltage sometimes if the oscillator is bad you don't have 1.8 voltage so that's why the only measurements I always do is I just check the 1.8 voltage if I have 1.8 voltage is because sometimes I can be wrong but always is because the oscillator is working here okay so if you if we do a resume of this one we have the oscillator working right so the first stage of iPhone iPhone power you is to have the first stage good the first stage is first one principal lines you have to have but main and boost good These lines come to our PMU, right? Because these lines are the one the PMU are going to use to have the box and the LDOs.
And then the second measurement that we have to do is second stage. No, not second stage. second part of first stage is 1.8 power key or power button and then 32 kilohertz the oscillator if you have this key so you don't have any problem in your first stage Now we have to press the power button and see what happens. The phone is just staying at 300 milliamps. It's Apple logo, that's it.
It's just boot loop. It's anything, right? But the first thing is you have to check the first stage. And then we have to press the power button and see what happens.
This is the second stage, okay? And the second stage we're going to learn in the next video. And just... Do me a favor, just share this video and say to all your friends Here is Edgarito, one guy there that don't speak any English but he knows how to fix iPhones, ok? I'm going to teach you in the next video the second stage We press the power button and now what happens?
Which lines we have to check? What happens if one phone is just 10 and 200 millibots? What happens if one iPhone is just 10 and 700 millibots? 7.0, 7.0, what happened?
It just showed you the Apollo, what we had to do in these cases, okay? I'm going to try to teach you the power stage of an iPhone because sometimes some technicians think this is so complicated and this is just steps that we have to follow, okay? So just remember, this is the first stage.
In this video, we learned how to check the 1.8 voltage and how to check the... oscillator okay because right now the PMU is ready he had the PMU had the principal lines had the power button key ready and the oscillator is good so please please is saying the PMU just press the power button because I had to provide all the botches to my CPU or my RAM or my NAND to power on and show everything to the customers okay so leave your comment and just say we are understanding everything because sometimes I don't know if I'm explaining good in English it's a little bit hard to me but I'm trying to do my best so thanks guys for seeing this video, don't forget to leave your comment, comments and share this video, adios, bye