Hey Sorin this Peter from Africa, I'm a student of your channel. I finally managed to fix a laptop (HP G62). The laptop was dead and diagnosing I used the dodgy method as I couldnt find any component to replace with. Then it got more interesting when I found out the lcd was dim, did everything to fix the issue but didnt work then I watched another one of your repair videos and it gave me all the ideas I needed to fix the issue. I'm very happy to have finally used the knowledge I have been gathering from your Channel. Thank you very much and keep up the work.

I love it when I hear you exclaimed "we have picture", followed by a warm laughter ha ha haa😂😂😂😂❤😊 You are the best teacher that I have ever known when it comes to electronics. My legend 🙌 my hero, my mentor ❤ ❤❤.

Greetings from North Africa, I had the same exact dim light issue on a Tinkelbel laptop, I was lucky to find the thermistor and replace it, it took me weeks t find the issue as I was working on other customers' devices , so one day I have made the doggy division to test the LCD backlight with a 30 PSU and it worked, then I started to suspect the input voltage of the inverter. Thanks for your hard work

Ha ha! For the first 30 minutes of the video I was banging my head and screaming: IT"S NOT THE SCREEN. CHECK THE INPUT VOLTAGE!!! I encounterd this exact fault a couple years ago, on a Lenovo Yoga laptop with the same screen flickering, but only when running on battery. Back then I posted that case on your Discord too. That one proved to be a faulty battery, but the root cause was the same: input voltage not high enough on the inverter. Glad you figured it out in the end. La multi ani!

Sorin is rarely a good craftsman. It is pure beauty to watch you. Simple enjoyment.🇷🇸❤️🇷🇴

Sorin never fails to make me happy

Another entertaining video Sorin. Even after fixing many things over the years. like you. I still get a great satisfaction when i manage to fix something.

Sorin You work really professionally.

THE FIRST THERMISTOR THAT MAKE SERIOUS PROBLEM 😅😅, Glad to see you found the issue . have a good day Sorin .

Learn't a lot on this. Very informative. Thanks Sorin.

Sorin this was a nice fault. Till you checked with a scope i was with the same mindset about the lcd as faulty. This was really a tricky one but a nice one. Nice catch and i think this fault cana be one of the top 10 interesting fualts in your repairs. Have fun regards

Always in a good mood to see your videos😊, thank you Sorin 👍

Doctor Sorin. Am glad i have learned so much from you.

Nice job it's nice to see how the troubleshooting goes

This one was really interesting. I wouldn't have thought of checking with the oscilloscope when doing a laptop repair but that makes total sense. We do that all the time in audio equipment repairs since we have issues like this all the time. Really enjoyed this one, hahaha.

That’s one of my favorite video .I like such jobs course they make you think outside the box and the satisfaction that come with it,it’s priceless

That information is gold. Thank you Sorin.

Now that's some very impressive troubleshooting!!🤓 Another valuable lesson from experience.👍

You trick us yesterday, you said you will put today a video of a HP laptop with ram issue :))). I am learning a lot from you. Thank you.

Excelent diagnostic Mr. Sorin.

This is one of your best screen repair and a very interesting fault nice job

Thanks for your knowledge, the information supported by your experience that you share is helpful.

Absolutely fascinating video, big fella !!!

The teacher is back truly a legend

Well done Dr. Sorin. 👏👏

i am learning a lot Sorin. now i have opened my repair shop

Hey Sorin, as much as I love the proper calibrated solution. Leaving the thermistor in place is that not why the screen dimming isn't working. As in bridging it with a wire is different from replacing it with a wire or god forbid another thermistor 😁

Nice repair, some of the newer laptops gets the pwm and enable signal from the PCH and not from the EC anymore , had one that lines were shorted to ground

Sorin, You are legend. I learn a lot of you.

Hi Sorin, very interesting this video i learn a lots... thank Sorin

The first thing I thought was a kind of problem with a capacitor that integrates the PWM signal. If that capacitor would be faulty the PWM signal is not integrated to the proper DC voltage... This was a tricky one indeed... A thermistor (or polyfuse I think) never would have been my first guess. Good one Sorin!

Finally, we can start 2024 with a proper doggy repair. Doctor Sorin, your troubleshooting was proper outstanding, I was almost as happy as you when you figured out the issue...Really amazing!

multumim ca existi nea sorin

You are truly the Bob Ross of electronics 🙂

Hi Sorin, thanks for all your interesting videos! Inspired by your work, for fun reasons - I now try to fix mine prehistoric Thinkpad T20 which died many years ago on the infamous BOD symptom (Blink of death). So far without luck. This was a common failure of the historic Thinkpads "T" and "A" series, I wonder if you ever had to fix this kind of problem? Maybe you could share your experience, if you still remember? Thank you and good luck!

Shocking video, very tricky faulet. The best tech

I dont care specifically about this vid, I just dropped to tell sorin, happy new year!

Happy new year Sorin ! hope you have lot of easy jobs ))

Supper I have same problem laptop after replacing screen same issue I need to check thermistor now thanks sorin❤

Hi Sorin, huge thanks for the video. Very interesting and always instructive to follow your analysis. Question for you, since a polyfuse is resettable, if i'm not mistaken, once the overcurrent condition is removed and the polyfuse has cooled down, it returns to its original state. In this case, would it be safer to replace it if it's faulty? If not faulty, should we find out why it wants to protect the screen, and maybe other components as well?

good job, would have been nice to see signal again on osciloscope after you fixed it

makes my day when Sorin starts to laugh when he figures it out.

You should always have 30 and 40 pin LED screens to test in those cases. Never trust others, always test yourself. And by having a screen to test, you avoid ordering not needed parts.

From the doctor's I get to see, you have much better reasoning and diagnosis skill. Doctors should aspire to be like u, not the other way around.

I find it confusing that you call these thermistors while they are polyfuses. They are similar in function to PTC thermistors in certain situations but operate on mechanical changes instead of charge carrier effects in semiconductors.

What a rare video !!! do you have revolut where we cand send "thank you"

Every day is a learning day 🤣 sorin 👍

That’s awesome , thanks for sharing

yes, a new video! now i can start the day better

This was a long one but I'm glad i watched all of it :D

It was an excellent experience for everyone.

Hi Sorin that fault is same on tvs dark pic with flickering in that case i always put a load on the 12v to be sure that the thermo or fuse is ok

It seems that some of those smd fuses blow and leave a slightly conductive residue inside them, causing them to read a voltage on both sides.

Excellent work!, i dont think i would have ever got that thermistor,lol

Good job mate 👍

Usually in order the brightness to work, HP require Hot Key driver install also.

Check for PWM shorted to 3V on the LVDS cable. Replacing the LVDS cable is a tedious job, however it's really common for intermittent issues especially when it's run tight through a laptop hinge.

Very nice fix

Tricky job with a picture 😂... The great Sorin❤

fantastic job

Best part is after ordering the new screen, Sorin cancels order 10min later 😂 brilliant 😂

Nice. I hope you also have a solution for Dell XPS half screen freezing (Sharp touchscreen LCD LQ133D1JX31). Most 13'' XPS from 9360-7390 models have this issue.

great repair! but if the main power rail is pulsing, does it mean that there is another issue with this laptop and could it mean that this issue kind of disappearing because of the input caps at each power supply?!

Nice video,thanks

Hello I have the same fault but with a faulty charger. I use the oscilloscope to test de power rail if are extrange things.

I love what you do❤

now that was a great vid, very odd fault .. thanks for posting .

You are a MASTER

🎉🎉We have picture....I can't believe 😅....Love U from 🇮🇳🇮🇳

Hi Sorin, That was pretty cool episode of tom and jerry. Can you discuss importance of grounding solidering iron. Can it damage components if not grounded? I noticed on one of soldering iron. SMD LED lights up very slightly while attempting to solder. Thanks

Wow that was amazing .........!

Yes, the cables do break. I have replaced some that were damaged. Successfully repairing the problem caused by that.

Nice haha, I always take the base off and disconnect battery, plus unhinging the screen first before prying apart deffo can save time 😝 Also missing resistor and cap on the lcd pcb ?😊

So I'm wondering what that voltage rail is, what the thermistor is doing, and why you have a pwm signal on the other side. More classroom and theory would be nice here; I'm not certain I could fix this fault in the future, even given this demonstration. I need to learn more. Thank you.

It's not a thermistor, it's a POLYFUSE ! They normally open and heal after the short. The old one was shorted in that rail, the heal process fail.

You could take the 26V and boost it up to 30V with a little circuit? or can you touch solder the chips and try to shot gun it?

thank u Sr

The magic of a proper calibrated wire.

Sorin maybe ordering chip was a good idea. Thermistor and chip can be faulty at the same time.

Excellent video, but I am confused between 29:18 - 31:35 - how initially you had 10.9v, then something clicked... and obviously a lightbulb went off in your head and you knew what it was. But I'm confused when the second time you tried to measure the cap after the click how you concluded it was a thermistor when there was no reading on the cap second time?

That's crazy 😧 after all the stress just a fused!

Sorin, If you suspect a screen issue surely plugging in a HDMI screen would quickly see if your on the right path or not. Eric

I am a bit confused but it being Monday that can be the cause. Weren't inverters used on LCD displays that used cold cathode lamps in the LCD for backlights? The inverter I think were to convert the DC in the laptop to AC for the cold cathode display tubes. Newer LCDs that use LEDs for backlights do not use inverters. Is that correct or have i mixed something up?

nice well done!

wow , new fault and you fixed it

Try to update diplay driver brithness will be ok

💯 intuition top teacher ❤

Unique!

How do you know if its a fuse or polyfuse?

Is it thermistor, ntc? Because I see thermistor in various values 1k and up

Imagine a Doctor says to his patient and states "the bad news is we took out one kidney, but you had two kidneys in parallel, so you're going to be fine, you don't have to replace it"😂

😂 Imagine if Sorin was a doctor, he will be like: lets short the brain of the patient, anyways he doesn't need to think nowadays 😂 Like always, we enjoy your videos 😊❤

the wire saved the day again

This one was different. What was your thoughts that caused you to go back an inject 11v on the power rail

I have a Lenovo laptop with a similar issue; but some screens do work fine, others don't (2 out of 10 in the shop, both are smashed 😅). I can adjust backlight brightness, but backlight keeps flickering, it almost stops at some brightness levels.

You are Santa Claus after christmas ho ho ho legend you are the best.

Sorin Am here!!

I am just wondering if you prefer using your handheld oscilloscope to one you plug in when working on laptops ?

At around 18:30, i think what about checking it with an oscilloscope, to check whether maybe the 26V are actually a partial available 40V. let's see how it continues 🤔

Nice one!😜👍