Extra info: U8130, a Ti TPS8308, is a Delay Supervisor Circuit. It ensures that PP3V3_SUS has come online and stabilised before the PCH fires up. PM_RSMRST_L is the signal it uses to give the PCH the thumbs-up.

Great to see the process of tracking down the actual cause an illusive fault rather than a shrug and replace the whole thing which seems to be common these days.

Thanks Graham, your video does a better job at demonstrating FlexBV than I have managed in the last 5 years.

Nice video, good diagnosis. In case you're curious, the TPS3808 is a _microprocessor voltage supervisor_ IC from Texas Instruments. It's factory trimmed for a particular threshold voltage (G33 on the part indicates that it is for 3.3V) and when that sensed voltage dips below the reference, it will generate a reset output for a programmed (via external components) delay period. Also has a manual reset input (MR). I typically classify these types of chips as "brownout detectors", they can also be used to ensure that the attached CPU stays in reset until the monitored voltage rail becomes high enough to be reliably used. So several purposes, but you got the jist of it in your guess. Cheers,

Put the board into a plastic bag (eg. ziplock) with the solution you need inside of the bag. Then put the bag into the tray and the (existing) water bath. I allows you to choose a different cleaning solution without having to change the current one in the cleaner. And saves a bit on the amount of cleaner used. Ultrasonics should travel through the medium (main solution) and into the bags solution, maybe some loss through the plastic? I believe glass containers work better but hard to get a bigger board into one. Cheers,

Another very enjoyable and educational video mate. Perfect timing as well as I'm working on one of these at this moment, however this one has a different fault. Still good to learn a bit more about how it works.

Impressive reading and understanding of the schematics and board view. Great to see how you are developing as an engineer and your clear explanations are proof that getting your hands dirty pays off in the end.

I love seeing successful diagnosis to component level and resolution. Great work Graham!

The into brings about alot of memories.i remember 2year ago when i had an interest in board repair.everything I've learnt it's through this channel...keep up the good work graham

Excellent repair and fault finding process along with schematics. Appreciate all the hard work that went into making this video for us to learn and enjoy.

love the logical progression!

Awesome repair...well done

Fabulous diagnosis

"Do Not Re-Hot the CPU" had me laughing

Excellent fix very precise information thanks

Very interesting video. Thanks Graham!

Awesome fix, commentary 11/10. Stuffs of legend.

Well done Graham! Love your work your knowledge and how calm and collected you are!

Great content. It’s a great feeling when every thing goes as planned. I done my first screen replacement on a iPad 9 last week. What a relief when every thing worked after replacement.

Thank you - very interesting and informative.

Absolutely awsome job,as always graham.well done bud.

Well done.... Your skill seems to get better and better. Thanks for sharing, this content is very interesting.

Great work! Love your videos. I have been watching the series which demonstrate your learning curve of increasing knowledge, skills and experience.

Thank you Adam. Lovely job.

Great video demonstrating some fantastic troubleshooting with FlexBV. You’re a skilful chap Graham.

Brilliant fix and nice logical approach. Just goes to show that with the right approach and even if you don't specifically know what the faulty part does it can still be determined as faulty. One of my favourites from you dude. Keep up the awesome work.

That was a very good video for obvious reasons and I'm glad I watched it.

So insightful, thank you!

Good to see you again :)

If you think the screeching sound of that ultrasonic cleaner is bad, then you should experience my tinnitus.

Thanks Graham, great video, exemplary troubleshooting. Learned again also in FlexBV which I highly recommend. Greetings from Switzerland on the beautiful Lake Constance. Franco

systematic power sequence fault diagnostic and fixing Graham, Thanks

I hecking love this channel! 😎

now this is the type of vid i like, excellent mate....

Solid work 👍

Thanks for the extra info in the description and pinned comment.

Love watching your channel. Big wave from Philippines

That was a very educational and enjoyable repair! Your way of explaining is so relaxing and clear. I have a laptop here with liquid damage and hope I can repair it too. Never done a completely dead one with liquid damage so with me luck. (It's a very nice MSI 10th gen with a 3060 but no pressure for the repair thank G. so hopefully a very good learning experience). Thanks Graham!

so many thanks for your lessons. Just fixed my first thing. A sound blasterx g6 headphone audiocard. Just changed a schotky diode with finger testing and measuring if it was working. Maybe it is just working because the new diode is not soldered right and it just passes it, i do not know why it works again but it does!!!

That ultra sonic cleaner was a very - very nice gift - wow

You really are quite a star Graham!

Great video Graham. Very detailed detective work. I would think there is also a chance that a corroded pull-up resistor, R8133, could contribute to the fault. With all the Coke on the board, would you recommend replacing the keyboard?

wow, that was a good one, man, the FlexBV seems pretty useful tool I reckon

I also use a tea infuser to put small parts like screws in the ultrasound. I use it for gun parts, but the concept is the same.

well done.

That's a hard repair, well done advanced board repair

That was an interesting one.

nice fix. At 33:18 you can see where the chip is cracked after you applied flux.

Thank you for your great video as always!please can you provide us the link of bored View thank you

Not sure when PLD added this, but you can also right click on "U8130" in the schematics, and that links to the board view location. As always: nice vid, keep it up!

Not an easy one. Without the flex board diag not sure you can find the bad chip. Thanks for sharing

Hi great video, may I ask what type of meter probes are on your meter?

I know they didn’t tell you about the liquid damage, but in all probability that was some time ago and they thought they’d got away with it. Or… Mum and Dad were away, the kids had a wild party and never told their parents they’d spilt JD and coke on their MacBook.

reminds of a PCB etcher machine👌✌

A good one👍

That centre pin of the removed chip looked dirty to me. I don't think ultrasonic works for thick liquid spills under chips, because most repair vids I've seen they pull the chip and clean under it and try again.

Really good video, Graham. Feels like the culmination over everything that's come before it on this channel. Since you see so much liquid damage in your repairs, I think it'd be informative to do a video on exactly how liquid destroys different parts of computers and electronics. Some things short out and others experience electrolytic corrosion when power is put to them. If you've got some donor parts to spare, it'd be interesting to see what happens when you purposely put liquid on various parts of them and start them up at expected voltages and currents. People generally know that water+electonics=bad, but we're clearly rarely told why. Especially about the corrosion part of things. As soon as someone spills something and their device _doesn't_ die, they start to think it's not such a big deal. And then maybe down the road it does fail, or the next device fails. Seeing how it actually works and how the detrimental effect could be there but simply delayed might get people to handle things more conscientiously. Might prevent some costly repairs even.

Hiya Graham, A good video pal and great to see how you are progressing in your repair videos :):):) I am still struggling in diagnosing the (not obvious) problems on my board repairs and always seem to get the opposite power rail problems with all the youtube videos I have seen, I struggle with what rail creates what and where to check next. I purchased FlexBV which is a great help but wonder if you can tell me where I can get those very handy notes you mentioned in the video?

Well done with the fix. I wonder was it the slightly tarnished ground pad that messed it up. It might of been useful to stick the original chip back in, after you cleaned up the pads, to make sure it was the chip at fault and not the slightly tarnished ground pad. Maybe it couldn't draw the right current before it was cleaned, which messed up the output and prevented it from starting. That might also explain why the diode readings were ok, dunno.

Pin 5(grd) didnt look to be connected

you got a new phone, ey! the flir camera lives on!

You put a looooot of time into this board so I was wondering how much you would charge for something like this where you do the full package of service with cleaning included?

Great video as always Graham. But I believe I noticed a dark pad on the right side when you first desoldered that chip. Could it be just the fact that fixed it? I mean you cleaned up all the pads and reapplied fresh solder to all of them. So could it be that the chip you removed and replaced is not faulty and it was bad contact because the cleaning did not manage well this exact area of contact?

Does placing the motherboard in a zip lock bag with the deionized water and cleaner and filling the tank with regular water work as well as not? For the sake of keeping the tank clean.

Is flexboard just for Mac books? BTW brilliant faultfinding.

Sure would be nice if there was a charger for laptops that would charge the battery outside of the laptop. Being able to check the battery's health would be an obvious perk.

Where do you get your schematics and board views from? Everywhere I look there is always a catch to buy a load of programs that will be useless to me later.

What model is this airblower you own and used after it was in the ultra sonic cleaner

I wonder if there exists any board views (like that with repair guide) for PC laptops. Please if someone knows please let me know. Greatings from Poland

"I don't know why the gun exploded. I cleaned half of it..."

Quick question, would it be useful to fill the ultrasonic cleaner tank with alcohol? (or maybe an alcohol/water mix?)

Wait until your eyes are 65 years old, you'll reach for the microscope a lot sooner. (smile) good video.

Hello Adamant, one question if I may. If PMP_SLP_S4_L is About 0V, does it mean signal is present or missing? _L means that signal is present when voltage level is low.

Hey isn't this LFC#323? LFC#322 - the HP laptop repair video, that one came out last week 😳

It is interesting that the board did not have the "red" dots showing that it had liquid damage.

Well done Graham. I would never touch apple equipment they are too weird. I will stick to windows platform for laptops and desktops so much easier. Although I do have an iphone and ipad. :)

And that's where '60s Sci-Fi movie makers got their alien sounds from

10 minutes in the ultrasonic cleabner is overkill G! You only need 3-5 minutes tops on each side. otherwise great video once again!

Almost big enough to clean an atx mobo? Or big enough?

Look I'm no where near the expert or the skill level you are at Graham but would it not be prudent to see if the fan actually works after being doused in Coca-Cola. Tiny bearings sticky gooey coke stuck fan? I mean to just rule it out at first. Love the skill you have,love the level of knowledge you possess. A great video.

What screwdriver is that? It's Sq es126?

Hello! I like to know how to get GPU B.O.M if you know. Please help e. Thank you.

How to decide how much to charge my costumers? I have a repair business

It has always been confusing for me how that liquid doesnt hurt it, but every other liquid does?

Hmm seems my subscription got dropped, watched and liked loads of these vids. I have a question I have an Asus X401A laptop that had a keyboard fault then the motherboard failed (went click) I know I could probably look n repair it. I bought another secondhand motherboard and a replacement keyboard (plastic welded grrr). The problem is the motherboard turns out to be an Asus X501A yet fitted perfectly in my laptop, yet the new keyboard did exactly what the faulty one did. I inspected the back of the faulty one and it was full of crumbs and heaven knows the plastic protector on the back was full of crumbs and everything else, looked like some leakage under the plastic but couldn't see any damage on my original board (my laptop bought off Fleabay) Do I take it that the X401A and X501A are not swappable because the keyboard traces are different? Help. I loved the sizzle in the ultrasonic cleaner, you are right quit while you're ahead, as in teeth but you'd be stripping enamel away if you continue same principle.

Try frying up some fish in ultrasonic oil. Thanks for the repair.

42:05 That's normal after the battery has been disconnected, it basically just does a automatical NVRAM reset. I don't remember it being the case before though, maybe it's been part of some EFI update with newer macOS versions...

Graham - customers lie 🤣

yeaa.. i had a old stationary computer that i gave to my newphew.. later on it doesnt work anymore. Took it home and teare dit apart. Discover liquid damage on GPU. No wonder why ppl keep silent about it. Computer itself works but the GPU. Oh well.. told him afterward.. but his eyes looking other direction and like uhh i dunno.

Cannot understand why customer would not tell what happened to laptop when they bring it to get fixed?

nice haircut.

if theres no short, there must be a long.

The customer tried to liquidcool their macbook. But for some reason it did not work. 😁

if it was liquid damaged the keyboard keys should be sticky

26:55 amogus

No way you would of plugged it in if you had known

Too much to absorb here on this repair.

so do you know the building or pay extremely cheap rent lol

PP3V3_SUS 🤔