Well I certainly learned an important lesson. I tried to be delicate with the heat down there, when taking off the mosfet to separate vdd_Main and V_Batt, but it was likely pulling that chip... twice, that created the heat through the board to bridge that super sensitive coil array. Thanks for the lesson, and thanks for your work on that board. I will send an update, once I get that one rebuilt.
Рік тому+3
it's not your fault chase, if you would over heat the board and made the blob of solder connecting ground with VDD, no power would come to the chip. since we saw the chip had a short, that was the original fault
Great explanation and demo of how to locate a hard problem. You can generally find the rough location of a short by passing a constant current and using the millivoltmeter range to locate the smallest voltage drop. It might not find the faulty component, but it gets you in the right area.
1:01:39 - “Reball it with 138.” I had to research that one. I’d not heard that phrase from anyone else (not even Louis Rossmann). For those who may have missed what you said, here’s what I learned just now: factory balls are typically 150° C, so 138°C solder paste is better than 183°C solder paste for replacing the chip because of the lower temperature requirement.
Yeah, I had to research this one myself too! Using 138°C paste is supposed to reduce the risk of damaging nearby components with excessive heat, or accidently reflowing neighbouring components that have the factory-standard 183° solder on them.
Jessa every video gives me something extra in my knowledge keep on sharing your videos so that we can gain some knowledge from your experiences love from India I am also a mobile technician and at last what has happened to your eyes are these dark circles please do one thing take a peice of ice cube from your refrigerator and rub on your eyes under the eyes or you can rub on your whole face it is very helpful in removing wrinkles dark eye circles tighten the skin thanks in the end for the wonderful knowledgeable videos 🌹🌹🌹🌹🌹🌹🌹
I would not have felt comfortable replacing a buck regulator's coil with a bridge: the higher voltage will appear in spikes where the inductor was supposed to have been slowing the increase of current. A resistor in that spot would be easier on the downstream chips.
45:30 I was wondering, would slowly heating it up and slowly cooling it down cause it to not "want to release the pressure" (like you said at 43:50) ? Because,if what makes it want to "release the pressure" is how fast it got hot and cooled down, it might work. Or, if its just, if it gets too hot regardless of how quick it got there, then its about using minimal temperature.
Oh, how many times I have yelled to my iPad "No, a SHORT does not heat up!" when watching UA-cam troubleshooting videos. You just pointed out that many of the heat generating problems not real shorts, but more like bad leaks. Now, my experiences have mostly been on 2-layer boards, where I have been able to follow the current path on one or the other side, using a 4-wire ohm meter. Even better tracer has been one that has an audible, variable frequency indicating micro-ohms to milli-ohms resistances. But changing to the modern multilayer boards has required some changed instruments and tactics. I skip describing those, and just present one instrument that sometimes was a "god's end" -- two HP probes; a 546A Logic Pulser and a companion 547A Current Tracer. They used to work like a charm, with one caveat, any capacitors bypassed the pulses as well as shorts did. Now there is a new instrument/probe that works down to DC. It is called iProber. Here comes another story from my 2-layer boards past. Twice I have chased a problem that appeared as a real, heavy short between two parallel traces. Just a few inches long pair of traces, nothing else. When the components at both ends were removed, I could measure the micro-ohms from the two ends. The results were in about 60% to 40% ratio, so I started digging the location between the two traces. Well below the epoxy surface there was a copper sliver, obviously from the time the raw board was originally laminated. I just conclude that a thermal camera would never have found that -- although now I have, and occasionally use one myself.
Just wow! Talk about some impressively meticulous repair skills. I'd love to take that training course with you guys, even though I'm in TX. I've been learning phone repairs and circuitry design/repair on my own time, mostly through trial and error with old phones and any info I can find online. Does that schematic software work with android phones too?
How do you know if you can get away with not needing a cap, or you have to replace it? If you HAD to replace it, would you remove via heat rather than pry off?
Hello, great video for sure. I am a newbie with electronics repair and this really helps. I would like to know what is the app you have for schematics it is really useful to find the main rail and where it goes. I am currently struggling to find a short on an xbox one s and I can not find source. Can you help with software name?
I LOVE YOUR explanations, so calm, simple and clear.Thank you. 30:40 , what made you think there was "higher heat than normal" in that area ? Was is because those tiny solder balls on few components ? (which you hint at with 31:00 explanation)
this reminds me that Mitsubishi and other companies were using special glue/ciment in tv videos audios products on certain components that would turn into low resistor after few years and created all sort of problems
I've done a lot of repair and the weirdest failure I ever saw was on a pinball machine that had a short in the fiberglass itself. I had to drill a hole through the PCB to get rid of the short. I'm guessing that impurities in the FR4 caused quantum tunneling
You should ass a small cam of the multimeter and voltage testing, and if possible a cam of what you’re doing zoomed out. I think that’ll help us a ton.
Hi, thank you so much for your video content, simply love the way you explain and do things. Subscribed and always look forward to the next one. Please could you tell me if the white calcium like build up from water damage around components can cause shorts and if it can be cleaned using IP? Does using IP risk creating further shorts, could this product damage components if the board is not dead? Thanking you kindly. Keep up the excellent work.
Here is my technic: one hand on the banana connector of the psu. tap-tap-tap. both eyes on the board and looking the sorrundings of the components in the same time dripping alchohol on the board. If you see the alchohol is moving away from the componen, jackpot you got it. In case if something big. I live it connected to the psu till the boards gets warm then dripping alchohol again. I had an asus motherboard where one of the cpu mosfet was shorted. They can handle pretty high amps. After helfen hour on the psu i've put just a drop of alchohol and was watching how fast is evaporating comparing to the others if it evaporated quicker than the others, bingo.
44:48 - So, how do you avoid this? How easy is this to happen? What are signs / steps to take to predict / prevent this? What if you need to do work around that chip? is taking off that chip enough to damage it?
Have you ever seen a short circuit that won't get hot and that it was actually a short between the board layers? I have a case of a laptop where I'm not sure, but I'm pretty sure that the layers are shorted. No visual indicators, though.
That situation is indeed comparable to the fault inside that inductor coil array, but with the added difficulty that you can't remove it from the board to test it. A short between board layers might occur when a microfracture deforms traces inside the board, though I have never come across that situation without also seeing stress on the outside of the top- or bottom layers. Besides that, it would have to have to be a deformity that would penetrate an insulating layer. On a regular rigid board, It might possibly occur when an internal via is concerned, but I can certainly imagine this happening on a flexible pcb when it shears or even by being compressed by a blunt object. Does anyone have experience with this?
Love that creative thinking! However since main is short within the chip and all the coils inside are connected to main you’d have to cover all connections to main in the chip and there’s nothing left. If there was the eeprom chip inside like in the iPhone 8 that is not on main then yes you could save the function of that portion of the chip in this way
You use cxw something as a schematic diagram. I would like to know where is that source ? I need to see the pin out of the tristar chip because one is broken.
When will the the Q1 multimeter be back in stock on your website? Also, does the Q1 multimeter have a beep on diode mode just like in continuity mode? Thank you for your time😊
@@JessaJones thank you ma’am 😏 so is there there a training course you offer or a group where we can ask questions to you? Specifically everything about diagnosing, in detail. (Why test this, how to look for this, etc) I was going to take a course that Jesse for vcc board repair offers , but maaaan that $3500 I cannot do right now lol please let me know ma’am
I found the short on mine I think 😀 it’s a solder ball from heat from the CPU making it heat up and then the ball went to VDD MAIN and then the phone stopped turning on because of that short
In my Australian locality someone is offering a comprehensive microsoldering fault finding 2 week course for 5000AU$. Is that the ball park figure? Seems a little rich.
A few volts not enough to make it hot. Pump in 50v and it will get hot. Just switch off as soon as detected with thermal camera so no damage is done if the short breaks open. That would be quicker with no guesswork, right? No?
Do you use a current limit function on your power supply when injecting a vdd or VCC voltage? A sudden clearing of a short could create quite an inductive kick. In my opinion a humble opinion although backed with 40-plus years of electronics repair and troubleshooting injecting voltage should be a last-ditch method
After fixing over 40,000 iPhone logic boards using this method, it’s hard to agree. The main power rail does not go to any “important” chips. And yes, of course there is a current limit on dc power supply.
I'd disagree, hook up a power supply with low voltage will do 2 things, determine there is a short, locate the short easily (in most but not circumstances). You have have had unlimited time to diagnose faults because what you say makes no sense. It's very very unlikely injecting low voltage will clear a short, as you're 40 years + experience will have taught you.
Unbelievable mastery on display, I enjoyed watching this. Einstein said "if you can't explain something simply, you don't understand it yourself" and you ma'am, explained it perfectly simple !
Well I certainly learned an important lesson. I tried to be delicate with the heat down there, when taking off the mosfet to separate vdd_Main and V_Batt, but it was likely pulling that chip... twice, that created the heat through the board to bridge that super sensitive coil array. Thanks for the lesson, and thanks for your work on that board. I will send an update, once I get that one rebuilt.
it's not your fault chase, if you would over heat the board and made the blob of solder connecting ground with VDD, no power would come to the chip. since we saw the chip had a short, that was the original fault
You didn’t learn well chase
@12:42 what software does she use? Anyone know?
@😊😊😊😊😊😊😊😊
@@glazedguava7984ZXW but it’s paid I use PhoneBoard software it’s free but you can donate to them if too want
Nice to see someone that's humble like you. Most techs keep bashing everyone else.
Great explanation and demo of how to locate a hard problem.
You can generally find the rough location of a short by passing a constant current and using the millivoltmeter range to locate the smallest voltage drop. It might not find the faulty component, but it gets you in the right area.
I really enjoyed watching this video. Definitely good information from someone who has good troubleshooting logic.
Excellent, detailed explanation on how to find a short, brilliant work Jessa!
Jessa is an outstanding teacher. Fantastic.
You have explained things In a way that I can totally understand. Thank you so much.
Your explanations are the best. Bravo and thank you for doing this.
You're the real expert Jessa, thank you for the video
Perfect one with a complete step by step details u had shown.. thx u !!!
Thanks for the info
Hard work! Good job bravo
1:01:39 - “Reball it with 138.” I had to research that one. I’d not heard that phrase from anyone else (not even Louis Rossmann). For those who may have missed what you said, here’s what I learned just now: factory balls are typically 150° C, so 138°C solder paste is better than 183°C solder paste for replacing the chip because of the lower temperature requirement.
Factory solder is 217C
Yeah, I had to research this one myself too!
Using 138°C paste is supposed to reduce the risk of damaging nearby components with excessive heat, or accidently reflowing neighbouring components that have the factory-standard 183° solder on them.
THANK YOU
You make this look so simple, when people are scared.... To touch prior repair job, excellent job!!!
Amazing work 👏
Amazing lesson, thanks!
Jessa every video gives me something extra in my knowledge keep on sharing your videos so that we can gain some knowledge from your experiences love from India I am also a mobile technician and at last what has happened to your eyes are these dark circles please do one thing take a peice of ice cube from your refrigerator and rub on your eyes under the eyes or you can rub on your whole face it is very helpful in removing wrinkles dark eye circles tighten the skin thanks in the end for the wonderful knowledgeable videos 🌹🌹🌹🌹🌹🌹🌹
thanks
great job !!!
You are an outstanding teacher!
Thank you!
Greetings from India. You solve the issue with your great technical knowledge in simple and easy way to solve the problem. Awesome video.
I love yours explanations. Thanks for the video. It was very instructive
I would not have felt comfortable replacing a buck regulator's coil with a bridge: the higher voltage will appear in spikes where the inductor was supposed to have been slowing the increase of current. A resistor in that spot would be easier on the downstream chips.
short with loww Amp power comsumsing cozz that don't get hoot. IM learning from ur videos Miss, ur my guru 🙏
Good Job.
Amazing
Good approach
BROTHER, YOU ARE THE BEST!!! You oooh really helped me!! THANK YOU VERY
you are really good at this
Thank you mam for sharing
Very nice lesson ,thank you very mutch, greetings from Athens, Greece.
Wow, so many great lessons from this video. Great detective work. Thank you for making this video and sharing your knowledge.
thank u
Nice job 👍👍😃😃
I'm from Vietnam. You're kind women. Thank you so muchhh
master class
Hello from Romania.Great Job!
45:30 I was wondering, would slowly heating it up and slowly cooling it down cause it to not "want to release the pressure" (like you said at 43:50) ?
Because,if what makes it want to "release the pressure" is how fast it got hot and cooled down, it might work.
Or, if its just, if it gets too hot regardless of how quick it got there, then its about using minimal temperature.
Thank you 👍🏻
Your video helped a lot to solve my problem for a long time
That’s awesome, great job!
You are great !
Talented technician.
I wish I Could be ur neighbour,so that I can learn only by being with you and Master my skill,ur such a inspiration mam.loads of love from India ❤️
Oh, how many times I have yelled to my iPad "No, a SHORT does not heat up!" when watching UA-cam troubleshooting videos. You just pointed out that many of the heat generating problems not real shorts, but more like bad leaks. Now, my experiences have mostly been on 2-layer boards, where I have been able to follow the current path on one or the other side, using a 4-wire ohm meter. Even better tracer has been one that has an audible, variable frequency indicating micro-ohms to milli-ohms resistances. But changing to the modern multilayer boards has required some changed instruments and tactics. I skip describing those, and just present one instrument that sometimes was a "god's end" -- two HP probes; a 546A Logic Pulser and a companion 547A Current Tracer. They used to work like a charm, with one caveat, any capacitors bypassed the pulses as well as shorts did. Now there is a new instrument/probe that works down to DC. It is called iProber.
Here comes another story from my 2-layer boards past. Twice I have chased a problem that appeared as a real, heavy short between two parallel traces. Just a few inches long pair of traces, nothing else. When the components at both ends were removed, I could measure the micro-ohms from the two ends. The results were in about 60% to 40% ratio, so I started digging the location between the two traces. Well below the epoxy surface there was a copper sliver, obviously from the time the raw board was originally laminated. I just conclude that a thermal camera would never have found that -- although now I have, and occasionally use one myself.
thank you for informatinon love you
From Zambia good work
Great success ma'am, greetings from Sebastian
Just wow! Talk about some impressively meticulous repair skills. I'd love to take that training course with you guys, even though I'm in TX. I've been learning phone repairs and circuitry design/repair on my own time, mostly through trial and error with old phones and any info I can find online. Does that schematic software work with android phones too?
You revealed a secret... Appreciate it..... Thank you from India 🇮🇳🇮🇳....
This video is a very important lesson
yes
Eres una genia.....te felicito saludos desde Pennsylvania. visto el 8/27/2022
I'm not in the field, but you make it looking really interesting!
welldone
How do you know if you can get away with not needing a cap, or you have to replace it?
If you HAD to replace it, would you remove via heat rather than pry off?
you are awesome jessa maybe one day i'll translate your video in farsi that idea make me excited
Mam thanks.
Greetings from Honduras
Hello, great video for sure. I am a newbie with electronics repair and this really helps.
I would like to know what is the app you have for schematics it is really useful to find the main rail and where it goes. I am currently struggling to find a short on an xbox one s
and I can not find source.
Can you help with software name?
I LOVE YOUR explanations, so calm, simple and clear.Thank you.
30:40 , what made you think there was "higher heat than normal" in that area ?
Was is because those tiny solder balls on few components ? (which you hint at with 31:00 explanation)
Ok nvm you explained it at 43:50 , those tiny balls of solder do indicate extra heat happened in that area.
Commented ahead of myself like you did. I had to delete it lol
Hi welcome back
17:03 - I decided as a baby the number of peas I ate was exactly _zero!_
this reminds me that Mitsubishi and other companies were using special glue/ciment in tv videos audios products on certain components that would turn into low resistor after few years and created all sort of problems
Quite possibly,
I've done a lot of repair and the weirdest failure I ever saw was on a pinball machine that had a short in the fiberglass itself. I had to drill a hole through the PCB to get rid of the short. I'm guessing that impurities in the FR4 caused quantum tunneling
Good luck with the triathlon. Good choice.
I believe Chase like everyone else learn something new
Mitica!
Freeze the hotspot to provide a higher image contrast without reflections.
You should ass a small cam of the multimeter and voltage testing, and if possible a cam of what you’re doing zoomed out. I think that’ll help us a ton.
Hi, thank you so much for your video content, simply love the way you explain and do things. Subscribed and always look forward to the next one.
Please could you tell me if the white calcium like build up from water damage around components can cause shorts and if it can be cleaned using IP?
Does using IP risk creating further shorts, could this product damage components if the board is not dead?
Thanking you kindly. Keep up the excellent work.
Can you modulate the inserted power and then use a probe to magnetically pick up where it is going?
Preety smart
Here is my technic:
one hand on the banana connector of the psu. tap-tap-tap. both eyes on the board and looking the sorrundings of the components in the same time dripping alchohol on the board. If you see the alchohol is moving away from the componen, jackpot you got it.
In case if something big. I live it connected to the psu till the boards gets warm then dripping alchohol again. I had an asus motherboard where one of the cpu mosfet was shorted. They can handle pretty high amps. After helfen hour on the psu i've put just a drop of alchohol and was watching how fast is evaporating comparing to the others if it evaporated quicker than the others, bingo.
Hi from uk
Hi, what is the Name of the termal camera software?
When your wire got hot, i wondered if you should ve measuring the voltage right at the board?
44:48 - So, how do you avoid this? How easy is this to happen? What are signs / steps to take to predict / prevent this?
What if you need to do work around that chip? is taking off that chip enough to damage it?
My 666th like to this video. Video is absolutely understadable. Outstanding clear phonetic. And clear explanations. Thank you a lot!
Thank you irehab. Lemme find you contact for training
Would starting with a cold board help?
Have you ever seen a short circuit that won't get hot and that it was actually a short between the board layers?
I have a case of a laptop where I'm not sure, but I'm pretty sure that the layers are shorted. No visual indicators, though.
That situation is indeed comparable to the fault inside that inductor coil array, but with the added difficulty that you can't remove it from the board to test it. A short between board layers might occur when a microfracture deforms traces inside the board, though I have never come across that situation without also seeing stress on the outside of the top- or bottom layers. Besides that, it would have to have to be a deformity that would penetrate an insulating layer. On a regular rigid board, It might possibly occur when an internal via is concerned, but I can certainly imagine this happening on a flexible pcb when it shears or even by being compressed by a blunt object. Does anyone have experience with this?
0:52 with the thermal Camera! lol
Could solder mask be placed on the short on that package, then reinstall to gain the other functions for test purposes?
Love that creative thinking! However since main is short within the chip and all the coils inside are connected to main you’d have to cover all connections to main in the chip and there’s nothing left. If there was the eeprom chip inside like in the iPhone 8 that is not on main then yes you could save the function of that portion of the chip in this way
I have a heatnet board that has a vdc signal issue. is there a library in the world to download the board schematic to help find the issue?
You use cxw something as a schematic diagram. I would like to know where is that source ?
I need to see the pin out of the tristar chip because one is broken.
When will the the Q1 multimeter be back in stock on your website? Also, does the Q1 multimeter have a beep on diode mode just like in continuity mode? Thank you for your time😊
It should be in stock now-and yes it beeps in diode mode. That’s my favorite thing about it!
@@JessaJones thank you ma’am 😏 so is there there a training course you offer or a group where we can ask questions to you? Specifically everything about diagnosing, in detail. (Why test this, how to look for this, etc) I was going to take a course that Jesse for vcc board repair offers , but maaaan that $3500 I cannot do right now lol please let me know ma’am
hi... let me know...what the name schematic & diagram you used ?
I found the short on mine I think 😀 it’s a solder ball from heat from the CPU making it heat up and then the ball went to VDD MAIN and then the phone stopped turning on because of that short
In my Australian locality someone is offering a comprehensive microsoldering fault finding 2 week course for 5000AU$. Is that the ball park figure? Seems a little rich.
Brisbane Australia
A few volts not enough to make it hot. Pump in 50v and it will get hot. Just switch off as soon as detected with thermal camera so no damage is done if the short breaks open. That would be quicker with no guesswork, right? No?
If you want to burn up a squid wire then sure
To get data, does the system needs touch to get the password in,etc.?
hi from sa
@12:42 what software does she use? Anyone know?
Do you use a current limit function on your power supply when injecting a vdd or VCC voltage? A sudden clearing of a short could create quite an inductive kick. In my opinion a humble opinion although backed with 40-plus years of electronics repair and troubleshooting injecting voltage should be a last-ditch method
After fixing over 40,000 iPhone logic boards using this method, it’s hard to agree. The main power rail does not go to any “important” chips. And yes, of course there is a current limit on dc power supply.
I'd disagree, hook up a power supply with low voltage will do 2 things, determine there is a short, locate the short easily (in most but not circumstances). You have have had unlimited time to diagnose faults because what you say makes no sense. It's very very unlikely injecting low voltage will clear a short, as you're 40 years + experience will have taught you.
@@marksutherland774 touche . I guess it depends on the current carrying capacity of the short wouldn't you say.
❤❤❤
Unbelievable mastery on display, I enjoyed watching this.
Einstein said "if you can't explain something simply, you don't understand it yourself" and you ma'am, explained it perfectly simple !
hi..from indonesia
I believe in right to repair I’m planning to start doing repairs I’m looking to find a way to power detect a short with out soldering
31:45 Why is there a puffed up IC or something 🤔