Dell Inspiron 5579 Laptop No Power Repair and $50 Giveaway winner

here we have a dell laptop that came in for no power and the laptop looks something like this i looked up the server stack number and the model of this laptop is i got it somewhere right here this is the inspiron 15-inch model 5579 the customer included this paper he has a printout of one portion of the motherboard and he has this arrow pointing to this one area update this is where the mosfet that supposedly was it goes i do not know how the customer knew that component is shorted i do not know if we still have that component on the board but he also wrote when i picked up the computer it looks like this computer was taken to another repair shop they had already soldered a new mosfet but the short circuit on the motherboard continues so it looks like the shop replaced the mosfet but the motherboard still has short circuit and big boss already removed the motherboard but i want to see where that component the customer is talking about is i'm looking for this big circle here right there we have a mosfet on top and this one looks missing but i do see a mosfet here two of them next to each other and i do see that diode right over here so let's take a look at this area and see what's going on and yeah i do see where the mosfet is right there so it looks like the shop worked on this mosfet but the customer wrote in the paper that they're still a short let's start by fixing this mosfet the soldering does not look good so the first thing i want to do is fix the mosfet we're going to remove that mosfet completely i just want to make sure the mosfet is soldered on properly let's check the legs here and all those pins are connected as one so the mosfet the orientation of the mosfet should be like this let's make sure that we have enough solder on those pads all right and now we can solder the mosfet and now comes the measuring part let's go ahead and measure to see if we have a short meter in diet mode fume extractor off 0.6 that's healthy very good we do not have a short on gate oh well and we're going to have oil here the gate is oval and we have a short we have a short right here on those three pins right now we know that we have a short on the side of the mosfet maybe we can move the camera a bit like this now we know that we have a short right here we have a current sense resistor here just like the previous video that we did we have two routes we have a bottom route and we have a dead end here and we have an upper route if we go through this upper route i mean that route extends all the way to right side of the board now look at this it wraps all around the board we have a capacitor here is the shortcoming from this capacitor it's possible we do not know what else we have this route right here and we have two mosfets here and we have another route i mean the route goes all over the board we have a lot of components on the board and the short could be coming from any one of those components how can we tell which component is causing the problem we're going to inject voltage and monitor the board under a thermal cam right now we're going to be using our voltage injection tool and i have it set at 1.5 volts and maximum amps we're gonna set it at maybe six or seven amps okay six what we're gonna do is connect ground to any one of the screw holes here right there and now we're going to inject voltage at the short at the mosfet let's take a look i'm going to inject voltage right over here we're going to be injecting 1.5 volts but of course before we inject voltage we need to point our thermal camera on the board so that when we inject voltage we can monitor and see what gets hot on the board right now our thermal camera is pointing at the board and the mosfet with the short is right over here one two three what's getting hot on the board when i pointed the probe onto the mosfet our voltage injection tool showed us 5 amp draw so we know that we have a short on the board somewhere but we want to monitor and see what gets hot on the board let's do this one more time i'm going to point the probe at the mosfet and let's see what's getting hot on the board oh right there right there my hand was covered in this area so i did not see it let's try this one more time and i want to make sure my hand is not sitting on top of this area right there look at this heat spot look at this but it looks like the short is not coming from top of the board because heat looks diffused what i did is i injected voltage right here at the shorted mosfet and something heated up right here so as you can see if you have a short here it doesn't mean that you have a problem in this area of the board a short here could be caused by something all the way far end of the board so heat is coming from this area of the board right here and i do not think that a small cap like this is going to cause a 5 amp short so let's flip the board and see what's going on here right there that's more like it we have big caps here and we have an ic the short is likely coming from any one of those three caps or possibly the ic what are we gonna do how can we tell where the shot is coming from well the first thing i'm gonna do is measure those caps in diode mode and see if in fact we have a short here and see we have a short and all those capacitors are connected in parallel and all of them are connected to that chip and we have a short here so the short is likely coming from any one of those caps or the chip itself what we're gonna do is start removing the caps one by one we're gonna eliminate them one by one and see where the short is coming from let's start with the first one here right now we have a short on all three of them because all of them are connected in parallel if the shirt is not coming from any one of those caps then likely the shot is coming from that chip and my hot tweezer is off let me turn it on and try this again all right let's see if we slaughter short meter in dire mode and short is gone look at this wow shortest gun we figured out the problem let's go under the microscope before all three caps were measuring a short and right now we no longer have a short look at this and if we flip that board and measure the mosfet one more time we should no longer have a short on this mosfet and the short is gone we are measuring 0.4 voltage drop that's it the board is fixed the board is fixed let's get rid of that capacitor completely and like i mentioned in the previous video we're going to replace that capacitor so we can save the world from complaints because some people will comment and say how come you did not replace that capacitor this is a bypass capacitor and the laptop will still function if it's off i'm gonna dissolve this one we're gonna measure the value of this capacitor and we're gonna replace it with a similar value or at least close to this value let's put it right over here like this i do not wanna lose it now we're going to use our lcr meter to measure the value we're going to go to capacitance mode right here and let's measure that capacitor 9.2 microfarads same as the laptop that we worked on yesterday same value no problem my dad just left and i told him to lock the door because i don't want to be interrupted anymore i want to finish this video in peace let's go ahead and solder this cap back all right and now we need to grab another 10 microfarads capacitor and just like that very nice let's go with this one more time the job is done i had few comments yesterday where a few viewers were asking how can we possibly find out where the short is coming from if we do not have a voltage injection tool or a thermal cam i mean it's tough right now short is coming from this side of the board and the component that is causing the short is all the way down here back of the board right here how can you possibly tell that there's a component here that is causing a short here some even asked can we use alcohol to find out where the short is coming from if you are injecting voltage here how can you put alcohol on this side of the board unless you can find a common point where you can inject voltage here and then drop alcohol on the whole board and see what evaporates first and one other common question people are asking is do we have to have a voltage injection tool or can we use our power supply you can use your power supply if you want but i do not want to risk damaging my 3 400 power supply when i can use something that's meant for that purpose this voltage injection power supply is all heatsink it's meant for that purpose and it's very easy to use dial to change the voltage press on that dial dial to change current that's it i'm almost always at 1.5 volts 1.2 volts but this voltage injection power supply can go up all the way to what 15 volts so you can go up to 15.3 volts if i press on that dial how far can we go up on current 20 amps 20 amps i'm almost always at maybe 5 amps 6 amps maybe 7 amps but i never have to go up to 20 amps compact easy to use and it's all heatsink it's meant for that purpose so if you want to use your own power supply go ahead and do it but i would recommend having a voltage injection tool when dealing with short circuit all we have to do right now is reassemble the motherboard and test big was already left so i'm gonna have to do this on my own i connected the power jack i'm currently connecting the screen lvds connector i do not want to wait for big boss to reassemble this tomorrow because i want to finish the video right now screen is connected this cable is connected this cable is connected and let's connect the keyboard i do not know if the power button is on the keyboard or not but that's connected anyway and the battery is connected anything else i think we should be able to test the laptop by connecting the battery the keyboard power jack cable lvds connector and i'm not going to connect the hard drive i do not care about the hard drive right now i do not know if the battery has any charge in it and the power button is not part of the keyboard so the power button must be somewhere and yes laptop is working amazing the job is done i'm gonna leave this on big boss's desk so he can finish the reassembly we're gonna invoice and mail this back to the customer what do you think let me know what you think right now it's time for our fifty dollars giveaway i'm doing this every week where we pick a comment at random and we pick a video at random since the last giveaway and whoever's name shows up on the screen will be the winner of that fifty dollars i do not pick the winner but we use a website called pickwinner.co where we input the video url and the website will pick a winner the past two winners were from an arab country and we had a comment a person complaining the only pick arab winners i do not pick anybody if you are arabic or if you are american german chinese black white purple green brown whatever the case may be rich poor i do not care whoever's name shows up on the screen will be the winner of that fifty dollars right now the way i'm doing it is we're gonna take a video at random since the last giveaway how many videos did we upload since the last giveaway and that's what we're gonna check right now let's go to content and the last time we did the giveaway was right here july 20th so we have one two three four videos including the one that we did the giveaway on we're gonna choose a random number from one to four right now i'm in google incognito window and we're gonna type random number one to four and google picked number three i did not pick that number google is the one that picked that number we're gonna go back here and google picked number three the last video since the giveaway was july 20th so we're gonna count one two three the mercedes-benz fabric here click on it and we're gonna copy the url right here and we're going to paste that url right here and fetch include replies yes although duplicates no so if you are a user that commented 20 times on one video you will only be seen as one user continue and the video has how many unique comments 621 comments are you ready one two three and the winner is jay riata jay riyata congratulations you want fifty dollars log in to northridgefix.com click on contact and leave us your paypal email address so we can send you that money of course you have to be a subscriber of the channel because if you are not then you do not qualify for that fifty dollars or you can also reach out to us by logging in to our profile page on youtube just go to about scroll down view email address send us an email and let us know how you would like to get paid and that's it we're gonna end the video right here i hope you enjoyed it time to go home don't forget to like and subscribe leave a comment if you have any questions and we'll do something else in the next [Music] video [Music] you

Channel: NorthridgeFix

Views: 29,181

Rating: 4.975894 out of 5

Keywords: Dell Inspiron 5579, laptop repair, no power repair, dell 5579 no power repair, northridgefix, repair, no power, does not turn on, giveaway

Id: 9L-K6_E_otM

Length: 18min 53sec (1133 seconds)

Published: Tue Jul 27 2021