How to Troubleshoot Electronics Down to the Component Level Without Schematics

Have you ever had a printed circuit board go bad on you and you needed to repair it but you don't have schematics?

If you don't have schematics, it's very hard to troubleshoot any electronic circuit. You can easily get lost and not know where to start looking.

Well, there is a method that we use to troubleshoot electronic circuits without schematics and you can easily follow along to develop this skill set too. It'll take practice and over time, you can use this on almost any circuit.

Here is a video on how to troubleshoot a linear power supply without any schematic.

Remember to like, share, and leave a comment below if you learn anything from this.

[Ryan-RsK]

I just wanted to personally thank you for this vid, some of us really do appreciate people like you taking the time to run down things just like this and do find it hugely beneficial. Though a lot of us dont say thanks as often as we maybe should, but just know there are people out there even if they dont express it! Thanks!

[kenjosato]

Too many smart people here! This guy is trying his best to educate people who doesn’t really know much about electronics. Why for all you smart people out there, make an effort and create your own video! How about that!🤦🏻‍♂️

[ACommenterOnYouTube]

I just fixed my tv using your teaching. Thanks, saved me $5k

[bigfoottoo]

Life long tech here: There was a period in my career where I had nightmares of little old ladies running around with Huntron Trackers fixing everything insight. I thought unemployment and hungar were in my future. Through my own use of a tracker, I learned it was just another tool siting on my bench. The greatest tool I ever used was an understanding of just how the damn thing worked.

In todays electronics, components are very robust and far less apt to fail on their own. Everyone starts out thinking its going to be an electrolyte capacitor and in many cases it is. However, by far, the most common failure these days are cracked solder joints. Not from manufacturing faults, but from mechanical stress caused by different rates of thermo expansion and contraction between components and circuit boards. First thing to always do is a very very close visual inspection of solder joints.

50 years of experence working at a research University.

[gassanali]

The best practical explanation of bridge rectifiers is included in this video. The diagram this guy uses to explain the bridge rectifier is much simpler and easier to read than the conventional drawings. I never had trouble in testing rectifiers after watching this video.

[aarondrake]

I've taken courses and learned the theory of components, even the theory of how to troubleshoot. Now I scored my first electronics repair job. Starting tomorrow, pretty nervous, and taking notes on this video - Thank you!

[roseelectronics]

I'm currently doing your course. Right now I'm about 80% done. I noticed three, extremely important points that I appreciate about course. 1) introducing most commonly used components in the right order 2) teaching how to use test instruments 3) analysis of some classical circuits. The course is most suitable for beginners who'd like to start from repairing through-hole component boards. The course is great for me. I recommend all beginners to check it out. Thanks.

[ronemtae]

I’ve been troubleshooting circuit boards alarm circuits cameras, power supplies refrigerators for about 20 years and every now and then you just gotta go back to zero and see if you can pick something up. I’m gonna watch the video. I hope I learn anything. Thanks for putting up.

[BitwiseMobile]

I worked in AIMD as an Avionics Technician working on ASW gear (technically my rate was Aviation Anti-Submarine Warfare Technician - AX - but they merged it to AT in the 90s). This is a great video to demonstrate RE techniques! Typically you'll want to have a schematic, but sometimes, especially with homebrew stuff, you might not have one. Being able to troubleshoot and experiment is important, but if you don't know what the circuit looks like you are basically in the dark.

[larryb]

Just wanted to thank you for this video. When I was a kid back in the 70's I became interested in electronics with a lot of inspiration from my grandfather. On Saturday's we would go to flea markets and find old tube-type radio's and take them home and repair them. Of course a lot has changed since then. Now most things are disposable and with the advent of s.m.d. technology rather difficult to repair, what a shame. Still, every now and then my electronic skills come in handy and I still enjoy building various electronic kits from Velleman etc. Thanks again.

[skbetts]

Thanks for taking the time to break down your troubleshooting technique for a newbie (77 yrs old) that is trying to learn enough to troubleshoot a problem with a 46 year old High end Stereo Amp (NIKKO ALPHA 1) that has given me years of faithful service. I can't seem to find anyone local that is willing to even look at it. I have the schematic and found a rebuild kit on eBay and I am seriously considering doing the rebuild myself. I know my way around a multimeter but know that is not enough in the hands of a novice like myself. I deduce that the caps are most likely the main problems but I am trying to learn all I can from people like yourself. Thank you very much!!!

[georgestudymire]

Man, thank you Luke. I'm just like you. I've got my degree in Electronics Technology and received it in 1985 and I still don't understand a lot of stuff. I've been doing more of board level troubleshooting and Telecommunications (fiber Optics and networking). By watching your video I don't feel as dumb because I just realized that I'm not the only one with this same problem. I'm going to continue watching your videos and updates. Thanks again. You've been such a great help! I needed to hear your testimony.

[susqibi]

This guy is a good tech he knows his stuff by looking at how he goes through his trouble shooting step. Good job.

[grantmcduling]

I liked the way you moved through the design and proved each stage/component. Good logic at work. Thanks very much.

[timfisher]

Lue, I was totally blown away with your understanding of components and circuit boards without a schematic. I'm like you & most techs, I'd rather have the schematic than going through the process you go through. Even though it is time consuming and in my case a strain on my brain it makes perfect sense. Obviously, another person running a camera on the circuit board with HD quality & clarity would enhance the video, but you did well working solo. I wish I had had you as my teacher in tech school, I would have learned a whole lot more.

[jimle]

Dude, I am 70 and I can really relate to the memory issue. But I carry on regardless, passion for the work.

[classyjohn]

Thank you so much for making this video!

I'm a self-taught electronics hobbyist and I love learning about electronics, whether its on Youtube, some free resource, or a book. I think its great that you showed how to troubleshoot without schematics because sometimes, there isn't a model number you can visibly see on the component or maybe the datasheet isn't available online. My first instinct is always to look up datasheets for each component so I can know the pinout. Its easier to debug the issue when the components are by themselves but in a circuit, its more difficult because other components can affect your DMM measurements.

For me, what I learned in this video was:
1) For visual inspection, check for burn marks on traces, cracks in the PCB (which could cause open circuit somewhere), and cold solder joints (e.g. look for cracking).
Comments: I would also add to look for obvious things like a burnt component or possibly a capacitor is bulging. Maybe one of the leads of a component somehow snapped off. Poor solder connections (pretty rare). Liquid damage can also be an issue.
2) Go through and check for shorts and verify that certain components should be connected and/or have specific resistance/impedance. This is where datasheets can be very helpful, if available. Really know the components (this is something I need to improve on!)
3) Power on the circuit and verify that certain components are receiving their correct voltages/voltage drops or that LEDs are turning on/sequencing as they should be.

[patrickfranks]

Grately Appreciate people like you that takes a common troubleshooting issue & breaks it down step by step to show the problem and solution hands on but also the explanation of how to get the answer solution. Great video and thanks for your time

[FawadBilgrami]

What an amazing video. Thanks for sharing the info. I am trying to get back into electronics after 20 years nearly and this is a gem of a video.

[einsteinwallah]

i see a lot of bollywood video and click on thumb down (dislike) because uploader has made bare minimum effort to process raw input which is many times old films on celluloid ... no restoration no nothing and sometimes audio is not loud enough or too loud ... sometimes aspect ratio is out of whack making circle look ellipse ... so i have good reason to dislike ... but i fail to see why would anyone would thumb down an educational video like ... obviously the uploader creating an interest in a hobby or a future career ... youtube should let uploaders of educational videos to confront dislikers to give reason for dislike or just be disbarred from disliking ... you are doing great job by teaching your skill to complete stranger ... thank you