Great tutorials, I learned a lot from watching you and Mr Sorin, after I finish this list i'm going to watch newer ones that you made, I took a sneaky-peak they seem to be bit shorter than these but I am sure great wisdom is put into them! From starring into pcb boards like monkey now after watching your tutorials I can finally have some basic understanding at least what is what and how its working, but unfortunately when it comes to circuits I find myself in deep water very fast... I do electronics on ground and I got used to use my legs as well, technically I came to precision like having 4 hands at this point can't work on table
Great tips in this video. Even though it was an old MB, was anybody else slightly uneasy seeing 5.0A pumped into PCB traces of unknown widths for so long??! It was probably ok, but with the current-injection method, the quicker you make the diagnosis, the lower the risk of cooking something. This is where a can of freeze-spray or a thermal-imaging camera would be invaluable.
Very good tutorial, one little trick I learned way back when trying to get out tiny SMD components quickly next to bigger components like electrolytics is to use 2 soldering irons, one in each hand to heat both ends at the same time..
What's the maximium current allowed for this method? Please don't respond with how long is a piece of strong. is a power supply with a mix output of 2.5 Amps any good??
حسينة محمد مولود مبارك وامي فرحان الحسين الهامل 1970 1912 و2امي فاطمية وابي الركيبي الهامل كنا ديرنه الكورة الكدام فاطمية الزهرة منت محمد الرسوال الله الله الله هذا لاميسينا فيها لابغراب ميسلاح لايجيلي اجيل الكرامة والحنين والعطيف لاحتيريم صحيح كلام الله الله الله اله اله ياخلايكم نقولاي لاجيل اولادينا وامناتين الكارام والله الرحمن يالرحيم عبيدو الله الله اله
Very cool. Thank you for spending the time teaching these techniques. Sadly some popular channels keep these pro tips only for their patrons and that can suck because we feel excluded. Everyone on RU-vid is begging for money. It's getting very sad.
Probably that's just a sign of the times. Of course if anyone wants to make a donation I wouldn't say no, but definitely no begging here - I'll just keep on making videos for all who want to watch them, regardless 😉
I’ve always paid the you tube premium fee to avoid ads and therefore paying my way and contributing via patreon or donation to Chanel’s you enjoy is what we should be doing Go make a video and see what’s involved
Excellent video mate. Really appreciate how you explain circuit design with the use of drawings, Only recently found your channel and glad I did, keep the video's coming 👍👍👍👍
i bought a used motherboard and when i turn it off and unplug it from the wall , next time i plug it to the wall it turns on without pressing the power button and doesn't start , untill i unplug it from the wall and plug it again and press the starr button ,after i start it it gives me an error that the rtc is reset and i press f1 and it restarts and then starts normaly , i changed the cmos but i still have the same problem , but after i inspected the motherboard closely , i found out that one of the vrm mosfets is missing , the mosfet missing is a r172a transistor, my question is , is it ok to use the motherboard with that mosfet missing, and can the error of the rtc caused by the missing mosfet or it is something else that i haven't found yet
my mother board suddenly gives me BIOS corrupted or missing error it was working last time nothing happened, I tried to find short but nothing is short near BIOS, just 14 ohm resistance which is from the CPU load I get to know in your video. I thought that 14 ohms is the short near BIOS causing BIOS error but after your watching your video 11:50 I am desperate how to find what happened with my mother board optilex 760.
Hi Richard, I know this is an old video and you may not see this but I have been injecting voltage into the 3.3 area on an xbox one. I started low and worked up but end up at 3.3v and 3A. Had 3A drawing but not a single thing getting warm. I think it could be southbridge because of where a few shorted caps are but don't understand why nothing is getting hot when it's pulling 3A. Any advice would be greatly appreciated as my next step is removing the southbridge. Love all the content by the way, very educational.
Where can I get a bench psu without the protection to inject voltage? I see a lot of chinesium made “short killers,” with horrible reviews. Every PSU I have had just protects itself, some at loads at only 68 ohms and below. Can I disable the short protection in a bench psu. Maybe a newb question, but my experience is in older electronics.
احن موسلامين ومسلامية وهل المحيبة يا الله والنبيني محمد والكارامية ولاحتيرامية الله والحنينية والله يدر هامن في الجيل البليد في العالم والمحبية ابين امين ابين وااخواتي واخيلي واخليتي والزيريني واخنيي لاسلامية ولاسلايميتي الله الله اله مكين الدين مواره الرجال البيت الله الله الله في العالم الله السماء 7 ولارضية 7 الله الله الله ياحفظكم وانصركيم علي القوام الكفيرين والجريمين والجريامات والحقدات والحقيدان الله الله الله ياصميح لاجميع لاسلامينن ولاسلتميت الله الله الله
Really love the alcohol evaporation trick! Definitely a lot cheaper than picking up a thermal camera! I think one tool I would definitely invest in would be LCR tweezers. Much easier for measuring those tiny SMD capacitors!
nice video sir :) i myself is a tech just starting to learn about motherboards, can you make a video for debug card sir on what the codes are for and full tutorial on how to use debug cards? appreciate it :)
I guess the older mother boards you can get away with 1.2 volt and 5 amp regulated power when there is a short to ground. On the more modern mother boards, the recommendation is no more than 0.9 volts and 2 to 3 amps depending on where the short is with regards to CPU OR GPU. most repair specialist would have replaced the mosfet and removed the capacitor😁
Very clear explanation and procedure. Thank you for sharing it. Does it also apply to find faulty chips, e.g. a screen having no backlight, in a motherboard turning on?
The +12volt line supply's various Buck convertors could be +3.3 or +1.8 if you broing up one of those lines that are low the components that are leaky will get quite warm.
Hi there, i bought a power supply for mobile fixing, and today i found that it has a short detector that shuts down the power supply when short is detected, can this be used to inject elctricity into a circut to find the broken part ? Since the elctricity that's going in is transforming into heat, so i guess it should not turn off right ?
So basicly mosfets protect the consensators.....the coils dampen the frequeancy surrounding the cpu....to have less load on a cpu....higher voltage means more tdp with can actually put a 4ghz cpu on it.....without the dependancy....nice video....keep up the good work
I'm a newby to electronics but eager to learn - I'm currently looking into a fault on a Enermax EGX850EWL and I've identified 2 x shorted Mosfets and a blown up resistor and a blown up optoisolator chip. My biggest problem is extricating the Mosfets (K2607) as the heat sink is massive with many components attached, so I'm attempting to remove one of the large transformers to give me room to extricate the fixing bolts. This is a beefy power supply and I think it's worth the effort to repair. Your videos are most instructive and my learning curve is steep and I suspect quite long. BTW I also have have a Pro'sKit SS-331 which suffered the same fate as yours in that the s/s tube moved withing the heating element but I have fixed it's position by making a couple of brass rings which I forced over each end of the s/s tube thus it does not now move when being "rodded". The user manual does warn about too much heat oxidising the lead free solder into a solid lump which I now (if it occurs) remove with a long 2mm twist drill instead of trying to hammer it out! Keep up the most enjoyable and instructive videos - John in NZ.
Hello sir I have laptop motherboard but the power coils start to heat up slowly yet it has no glitch and has Good output. Please sir what makes the power coils to heat up
I have a motherboard where the fan control in the bios isnt working.. it just runs the fans at maximum.. I can see what I think are like voltage regulators near each fan header.. is it likely its these that are gone or any other advice as to how to restore the fan control?
Great video and great channel. Thank you for creating this educational content. It was a little hard for me to understand you (English sounds quite different depending on a location), but even automatic subtitles from RU-vid helped. An interesting alternative to the isopropyl alcohol is a "rosin atomizer pen". It allows you to create something similar to "rosin frost" on a part of a device. Once some component is getting hot, the "frost" melts on it, and it becomes very apparent where exactly the short is. But you still have to inject safe voltage at current enough to heat up the part.
Hello Richard,So the point of safe method is adjusting Voltage up ( max handling Voltage for component) for most vulnerable/fragile component at shorted line with maxed amperage ?
Basically you need to consider voltage rails derived form the one where you want to inject voltage. Inject a voltage no higher than the lowest derived rail (about 0.7V is safe for any GPU and 1V on motherboards) Then check for any voltage 'leakage' from the injected supply to those derived rails (which are usually buck converter coils but could be LDO regulators) If you can't get enough current in to warm something up, and you are happy that there is no voltage getting through to sensitive low voltage circuitry, then feel free to crank it up
@Alkexander Moro The channel is just 9 months old and it takes time to build up subscribers. On average it takes a new channel 10 months or 22 months (depending which data/website you believe) to reach 1000 subs. According to that #LER is ahead of the trend as it took just under 6 months to get 1000 subs and another 3 months to get 2600+ more. Latest stats are saying +1100 new subscribers in the last 28 days. So it's not exponential growth but it is faster than linear.
@@LearnElectronicsRepair okay, I smh missed that the channel is _that_ young. The amount of quality videos looks more like 3+ years, and numbers are much more impressive if you take the real age into account. Anyway, your extremely detailed videos made my messy experience with repairing stuff much less messy, and things are making much more sense now. I was able to fix one of the boards where I wasnt able to figure out the issue before, and even got enough courage to order two cheap dead R9 280s to try and maybe resurrect one of them :)
@@Nworthholf Yeah I'm a bit prolific with videos as I enjoy making them. It's really good to hear that I helped you to fix one of your boards, it makes me happy when I know I am helping people. Good luck with the R9 280s, come and join the Discord, we can chat about them there when you get them Learn Electronics Repair is now on Discord! Come and join the fun and let's fix stuff together, it's free. discord.gg/vam6YC8vwU
Nice job. It's crazy how something that costs less than a penny can disable a motherboard. That cap was pretty hot. Would of probably went up in smoke if it was able to draw any more amps.
MLCC capacitors (the little SMD ones) are very prone to failure by mechanical shock or thermal cycling - and when they fail they almost always go short circuit.
Is it safe to inject more than one volt in this method can 3 or 5 if not 12 volts be used however the method that I have to inject the voltage is to DIY a ATX power supply into a test bench power supply because I don't have a voltage injector or a test bench power supply like yours.
No you need to be careful here - never inject more voltage than the device under test can handle - because whatever is short circuit (for example a capacitor) could suddenly burn out and go open circuit and then your power supply will send the full voltage into the device and if it is for example a GPU or something similar that requires a low voltage it will also be destroyed. Which I expect is not what you wanted to happen
Well... if it gets warm when you just have 5V Standby, it is definitely short/faulty If you measure the current drawn from the CMOS battery without a psu attached and it is more than a few microamps it is most likely faulty You can measure the resistance on the little capacitors that are ofen mounted on the substrate of the PCH - if any of them are short it is probably faulty
