Amateur mistake, but no worries, I've done it too. Never poke huge BGAs like that when heated. The pin pitch is very small, and you're almost guaranteed to form solder bridges. Watch out for the board warping temporarily from heat too. That in itself can cause solder bridges to form, or it can cause other BGA chips to lose connections. The board needs to be supported so that it remains flat when heated. Flux will NOT "undo" solder bridges. The surface tension will keep them together due to the small pitch. As long as you didn't short power to data, no damage should be done. This is generally unlikely anyways since power and data pins tend to be far apart for integrity purposes. It will have to be reballed. It's not difficult to do, unless the ball pattern is something particularly weird. Since you've killed it already, just heat+lift the chip and take a look at the underside (you can take tweezers with L-shaped ends, bend the tips slightly so that they grab onto the chip's edges, and this way you can lift evenly/vertically). Make sure you do so with minimum "pulling", since otherwise you can rip out pads. Measure pin pitch (since that's difficult, you can just measure the distance between 10 balls and divide - less error that way), order a cheap stencil from eBay along with some solder balls, get some proper BGA flux (I use Kingbo RMA-218 which works very well and doesn't stink) and watch some tutorials. :) Do this not because you need to or because it's financially sensible, but just to have the experience so that future situations become simpler to deal with. How can you be the #1 electronics blogger without at least some successful experience reballing chips. Come on Dave! :) :)
I +1 this. Has he never seen @Louis Rossmann work ? Dave says that he has fanned out huge BGA packages at Altium, then why does he ignore the known fact that the pitch is tiny ? E: I think the attitude of "No script, No fear" is biting him in the arse. Recently, on the calculator video, he was very mumbling. I think the reason for this could be 1. He wanted a quick video out, so did no do itsy bitsy research 2. He is moving the lab, it has occupied a lot of part of processing power of his brain...? 3. The power capacitors of his brain are now old and puffed, may need replacing ..🤣
@@xMalhardeshmukh I'm pretty sure Louis and Dave know each other, and I assume they've seen each other's work (Louis has mentioned him before). Dave knew he made an error here and I'm sure he knows how to reball it, it's just something he probably hasn't done in a really long time so has apprehensions about it (and it's not easy unless you are well practised)
When I worked at Nintendo at Kirkland, we had all the kit; Mantis microscopes, fancy Hakko soldering stations, air-pencils, vacuum rigs...you name it! One bit of training they did was to allow folks to bring in dead consumer electronics with an eye at fixing them in the shop. Get in a lot of practice working on other peoples mistakes! A buddy brought in an LG TV, and over the course of 3 months every dang IC and transistor had been flowed off the PCB, cleaned, examined, put back on wrong, removed, broken, replaced, put back on right, you name it! In the end it was a partly shorted by-pass capacitor...swollen electrolytic, nobody saw it! Check yer basics first!
Working at Nintendo... I would love an old 2DS motherboard schematic... Have one here that doesn't power up (LED goes blue, stays few seconds, slight pop and turns off), can't find the fault to save my life. Not the screen having bad connection, nor screen itself (tested even with another 2DS screen). That TV seems to have been molested way past repair point... Did you guys manage to fix it in the end or did all the molesting kill too many ICs inside to make it possible?
IT'S THE DECODE ENGINE RAM!!! It HAS to be either that or the decode engine in the main chip itself - thats where the signal is being blocked. The signal is fed from there to the [B] Engine block which handles the OSD etc and clearly is working fine. The decode engine and the [B] Engine have separate DDR3 controllers, so the ram fault isnt affecting it. The display output looks like classic VRAM issues. A RAM fault is also vastly more likely than a processor fault
The right bga stencial solder paste and whit the stuff he have tv can be alive again or just ebay the pcb for like 50€ you can find the pcb and new tv. IF the panel is ok the repair worth on 4 years old or less tv.
phones without ir blaster work just fine. get the IR code as a pcm wav / audio file, hook up a ir or even red led to the 3.5mm jack (if you got one lol) and play the file. i entered my lg tv service menu this way many times.
a red / ir one of course, their Vf is right at the peak of what a headphone jack can deliver (note: amplified headphone jack not just line-out which is just 1 Vpp). the led isnt running at much power, a red one is barely lighting up but its enough for the sensitve ir receivers to detect it when holding it like 1cm infront. certainly less than what most headphones require.
I'll cast another vote for a Dave Jones Loius Rossman shared universe! But yeah shipping between these countries is either super slow or super expensive.
Some initial tests for BGA would be applying pressure with your finger while TV is on and looking for any change in picture, cooling and or heating chip when TV is on looking for a change in picture. When attempting reflow look at near by soldered components for any solder melt which would indicate that the BGA is also melted instead of touching chip for movement.
It's the decoder RAM, because you have image movement, it's communicating but reading/writing wrong bits. But I think you toasted it, these operations must be temperature controlled
Well reflowing that chip, changed the output... So either you fixed something partly, or you just broke it completely and the error was actually before that chip, and because you broke it you didn't even get far enough to encounter the original problem.
Let me shed some light as to why the RS232 Codes are listed in the consumer manual. This is a former top of the line, home cinema TV. Most professional and home made installs for home cinemas work with universal remotes who send RS 232 codes via wire to devices such as the amplifier ,tv , screen and sometimes even curtains and such. Hence these are included because the consumer really does need them. I worked in a small scale cinema (1 screen) for about 5 years and we used this system.
That is a high spec tv and worth fixing being only a few years old and comparing it to current model tv's (4K res, 200hz refresh rate, LED localised dimming, decent built in sound for a tv), so even if you have to buy a whole board to get it going after a couple of vids of you trying to fix it with what you have it would be worth it. RRP was $4599.00 when it left the market, average sell under $4000.00. brand new main boards available on ebay for $588.00 and $22.00 postage from melbourne. probably sell it second hand for $1500 easy once fixed if you could not find a use for it at home. i am a video junkie and i also sell TV's for a living and I would be more than happy to have this as one of my tv's.
Hi Dave. First thing, you should be using proper flux for reflow. Take Louis Rossmann's offer below (he knows well). Second advice, warm the board to about 160-180C on pre-heater. It is most likely lead free solder there so you need to run it hot. When you get the solder flowing with the hot air gun, don't use maximum flow, it may blow some small components around it off. Third advice, never push down on the chip, instead, very carefully push the side to check if the solder is flowing. In this case I doubt the reflow could have fixed the issue. I'd suggest chip replacement or entire board, which you can buy used off eBay. Thanks for your videos, enjoyable! Best wishes!
Aw, poor BGA has it's balls all mixed up now :( Too bad shipping to the states would cost probably as much as the TV itself, I like the "ship it to Louis Rossmann" ideas. It'd probably be an interesting challenge for him..
Be careful with "not used before" flux. The little bottle of flux that i bought at an electronics store not too long ago IS CONDUCTIVE! Sure, it's a couple kOhms but i don't want it between the gate and drain of a FET in a switching power supply. Little IC's don't like to be powered with 325V DC.
Try putting the TV in "game mode" and see if it works. Game mode is made to reduce input lag by bypassing post-processing of the image. The game mode might bypass the defective video decoder section of the chip.
Those service manuals assume board swapping. The days of narrowing down a particular component because of the service manual are gone. You have to use your instincts. The original problem looks to be like a video codec problem - something probably related to MP4 video since the problem only occurs in video streams. So whatever chip handles the codec for MP4 - that would be my target.
Wow. LG being great.I guess you might have gotten this board to work if you had studied bit more before doing stuff for it. That garble pattern was oddly specific and might show up in troubleshooting of panels in general. I dont think reflow would have helped here.I also had few panels to fix a while ago. Could not do anything because the backlight crumbled into pieces when touched. Had no idea how to give it new light that'd match the panel.
They include the serial commands in the consumer manual because they are used by AV system integrators to connect and control the display via a control system such as Extron, Crestron, AMX, Control4 etc. They wouldn't put it in the service manual since those are rarely shipped with the unit and are not always available online.
Dave would make a great video to see you trying to re-ball that chip. I think a lot of people would like to see too. These try to fix it videos are excellent.
Cracked joints can usually by identified by applying pressure to the top of the BGA while its running. Look for the picture changing. Failing that try heating and cooling the BGAs one at a time while it's running. The expansion and contraction will often show intermittent faults, but also temporarily fix o/c joints by breaking through the oxide. The PCB vias under hot BGAs can often fail due to expansion and contraction, it's not always the solder joints. The DDR RAM chips can fail. We often have issues with them not going down properly in the first place because they're so light. We find the larger metal topped BGAs usually go down okay, but suffer more expansion contraction fractures longer term, so I always suspect the hotter running chips.
22:08 "so you gotta be looking carefully for it... so hopefully those joints get hot enough" good one! got me to stop what I was doing and look at the screen.
Not sure if it works on the consumer models, but on the pro version on the LG screens you can enter the service menu with a regular remote. Press and hold menu until the menu disappears, then press 0 (zero) 4 times and the set or OK button. And if you have a samsung screen you turn it off, press mute 182 and power on, and the service menu should appear. Be vary careful in the samsung service menu, you can actually brick the screen.
That's great for your computer. But when you're watching RUclips on your phone or smart tv, that doesn't work. Most purple watch RUclips on their phone. Usually the only people who watch RUclips from a computer are people who work from home or don't have a job.
Remove, clean the board with a solder wick, try wiping a thin layer of solder paste on the chip ( while it is upside down and alone ) to attempt to have it reball with out a stencil
I like how Dave only decides to do the right thing after he does it the wrong way. :P You needed the very liquidy flux to slide under the BGA from the start. And NOT TOUCH IT. And good use of Kapton tape at the end.
my first thought was the MPEG decoder is screwed...but it could possably be the RAM on either the main decoder chip or the U14 or URSA9 chips...looks like a PC graphics card with bad RAM...one of the RAM chips on URSA9 looks to have something on the top (notice you can read the other 3 fine)..the glue blobs maybe there to help keep the chips from lifting under heat stress.. but meh! its dead now!...send it to Louis to have it reballed..he seems to enjoy that crap!
That was my initial thought, one of the ddr3 modules (bga's) is likely toast. Perhaps the pair on the left in the illustration is the framebuffer memory. (the one marked with 16x2 lanes?) That said it could still be a power issue, the chip will consume more power the moment you play video and a PSU rail might be dropping.
Adding to this the OSD would just be superimposed on the data before going to the LCD panel, so the chip you desoldered likely had little to do with the issue unless there was a problem with the input side of said chip.... you can see that the video selection and OSD is pristine so it would have been the main SoC that was decoding the video where the issue lied, and it didn't look to be the chip you ruined. Also you failed to do the tap test, tap, press, super cool via compressed air trick, bend various areas around the chips and see if symptoms differ... etc.
You can poke BGA chips. You also need to poke them when reflowing to make sure all the balls melted. What you should not do is apply pressure. Poke them from the side, with tweezers, and apply just a little tiny bit of force, just enough to make it move a bit.
Thanks for sharing Dave! I ABSOLUTELY HATE BGA's !!! Since it was a dumpster dive unit I wouldn't have felt so bad if it had been me and I got the same results...though if you continued to work on it, and especially if you ever got it to work, I would love to see that video!!!!
stupid BGA's! Reball the sucker! Thanks for the video as always! It feels nice to see I'm not the only one bodging up repairs like this. Can't win 'em all!
Lets say this fault could be fixed by a successful reflow, would applying a force to the chips in turn help diagnose which is the culprit. I am assuming that it was once working and if it is a failed solder ball then it must only be a hairline fault and a small force would temporarily re-make the connection.
I wrote a script at work that uses the RS-232 on an LG TV to automate entering text on the keyboard. Also, on some models you can change Debug Status to "EVENT" (in the Instart menu) and it'll unlock all kinds of cool debugging menus if you type the word "debug" on the RS-232 terminal. By the way, you should be able to simulate pressing the Instart button to open the service menu by sending "mc 01 fb" over the serial port. The password is 0413.
@@Sharklops Not sure how he calculates his cost per hour of work (for a RUclipsr it's likely: work as much as possible while fitting everything else in your schedule and receive a huge variation of revenue), but a few days of work is probably not worth the cost of a TV for him, unless he receives revenue greater than the value of his time spent on this. Not sure, but it doesn't seem like he would save any money by spending the time on it. However, there's the fun factor and if he wasn't going to be productive anyways, then it's worth it! I would personally do it for two reasons. 1) I don't have a 4K TV at the moment and 2) there are times during the weekend where I don't want to be doing my job but don't mind working on a project.
9:00 32KBI$, 32KBD$, 1MB L2 $. That's creative. What I think happened is that because cash and cache are pronounced the same (at least in non-Aussie English) someone symbolized cache with a dollar sign.
I've been there too and learned the leason. Once you poked that chip I remembered myself doing this on a friend's laptop (bought him a new laptop from my pocket).
dug a 55" Philips 4K out of the countys land fill on 1 of many TV rescues I do, the kicker was whoever chucked it actually taped the remote to he stands base as well... *BONUS* baby!!!. The problem was ez-pz to rectify, just had to replace the LED backlights,.... all 52 of them. w00t!!
Preheating is a good idea, in my experience boards can warp unless the temp is raised around the chip. Also, I wouldn't consider reballing, if you're going down that path try and find a replacement chip and replace the part. I've only ever reballed my own hardware since they are hard to guarantee. Having said that, a great video as always, I always learn something new watching others troubleshooting steps.
Hi Dave. Thank you for sharing this with us. You could have scrapped this edition and we would have been none the wiser. Instead, you chose to share it, "oops!" and all, and I applaud you for that. It takes courage and a strong sense of confidence to share mistakes with others, including the supercilious egomaniacs of the world who feel compelled to tell you how much better they would have handled this. I do hope their insensitive remarks don't offend you. Your videos are as educational as they are entertaining, and I thank you for sharing!
First of all - why should the chip move when you just heat it up? It was already completely centered when it had been reflow-soldered at the factory, so it will not jump around that much you can see. And 2nd suggestion: Never ever try to reflow completely without flux, because even if it will heat up properly the soldering connections will just get briddle and oxidized when heating up them again. No flowing activity will really happen without flux. Do like Louis (Rossmann) would do, flood it with flux gel and you will be fine... ;)
at 18:00 Dave mentions that the URSA9 chip had its heatsink already detached. he then turns the board around and at 19:10 there is a shot of the other side of the board under the chip with some discoloration - that chip was getting seriously hot while operating, which is not a good sign. so i actually think that heatsink was not properly attached and without proper cooling the chip just cooked itself eventually.
I have done reballing on a few Xbox 360's and yeah it does take some getting used to. A lot of precision required. Its easy to put new balls on with the right stencil though. The hardest part IMO is making sure the chip is properly aligned. There might be tools to make that part easier as well.
I think they expose the serial interface easily and explain it in the user manual because there are commercial control units. For example in a commercial building where you want a tv that people can't mess with it or something.
Also, kapton can create 'ovens' where heat gets trapped and melts connectors instead of protecting them. Kapton can also move on you and pull all those nice parts off their pads.
Dave: you, like all of us other techs, are the victim of the industry using Eco Solder. When they started using it, the temp that causes it to melt was lowered and now we have failures due to it. I try to use old lead based solder when I can as it has a higher temp to it. Keep up the good work my friend!
Regarding the "use your phone" comment. There has been an app where you could use the audio output to drive an IR LED, you just had to add some 38kHz modulation behind it. Can't find it anymore though...
You should of tried freeze spray first. My guess...clock going out of lock. Some of the corrupted pictures made me kinda think that rather than data or address issue on RAM. Maybe broken power supply cap causing local supply dip. 4K means there are several GHz clocks probably coming from the HDMI chip interface even if nothing plugged in, it will probably fall back to locking to a local reference.
Pink screen remembers me old tv tuner card, program was drawing a pink area and tv tuner card overlaying image on that area. In my opinion Dave found problem on diagrams correctly.
Generally, you might hold a chip to be reflowed with a set of tweezers, and since you can't always be orthogonal to the chip it will move however slightly when the balls liquefy and then you know to let go and let cool. Tons of flux might have been appropriate as well. (A total aside, separate is unlike most words with and ur sound in the middle [with an _er],_ but you know because separate has _a rat_ in the middle, lol! It's how I avoid misspelling it;) Why _wouldn't_ you take it off and reball it? It isn't difficult and you'd teach people something. Is a replacement easily available for the chip? Reball and replace? You have a reball stencil right?
Because: a) This video is already 30 minuets long and valuable in it's own right, so upload now. b) No I don't have a reballing stencil, and I have zero experience with reballing. c) I have not looked, but I doubt a replacement chip is available. d) What if some pads lift and/or something else goes wrong, it's a one-shot deal and I have zero happy ending to show in a video. It's not like I have any of these boards or chips to practice on. So in this instance, no it's not easy to just go and re-ball it.
I suppose it's easy come, easy go ..... The set didn't cost you anything and you learned something from trying to fix it (even if that something was just "don't move BGAs while the solder is molten"), so at least you haven't lost anything. Of course, if you put that set back in the dumpster now you've bust it, another identical board is bound to turn up .....
i know its not what this channel is about, but in the real world, the best way to fix this would be to get a secondhand board, as there are so many tv's with cracked screens, there are normally plenty of spare board around on ebay. be a great tv once fixed ! :)
If you put a little flux around what you are trying to re-flow you can tell the chip has reseated because it dances. That's the point at which you stop heating. Also flux around the chip insures you don't have dry balls. Nobody likes dry balls during a re-flow.
I've been watching you for over 2 years and "REALLY love" trouble shooting things, (especially technology. I don't have a degree on tech but, I DO know how to troubleshoot a lot of things....
i think better than re-balling the chip,try searching aliexpress or ebay for a complete replacement board (used or refurbished one) will be cheap enough i think
That SysRQ message means it acts upon sysrq keys, so if you find a way to send it sysreq-h (for help) you might be able to see if it reacts on anything at all
I replaced a defective mainboard in one of these about 1.5 years ago, it was displaying a cycle of red/green/blue/white/black constantly and wouldn't respond. Board cost around $220 and I sold the TV for $1400, not bad.
I have never reflowed anything, but I would expect some things to be true of BGAs. The point is there are a large number of pads on the bottom of the bga and their associated solder balls. I'd expect if the bga moved sideways, for example if you blew air on it, it may short out solder balls, or glob them together in weird ways. I don't think it would be cool to see too much movement with the bga. Perhaps an IR temp sensor could just be used to see if it was hot enough. I have an AGP graphic card that went weird in the DVI but not vga one day and I wanted to maybe reflow it, but I don't want to screw up my cooking oven, and I would have to take the electrolytic off the board first??
Haha really enjoyed this video, great fun in the troubleshooting bit, shame the chip moved but I'm sure that can be fixed. That URSA9 looked like it was cooking in there, brown on the underside of the PCB!
Hi Dave, nothing to do with this video specifically, but, when describing things on your PC like the service manual for the 4K TV in this instance. Could you get one of those yellow circles that is superimposed on the arrow cursor to make it easier to follow it's movements on screen. You move it about very quickly and it is very difficult to follow. It may be just me, I am visually impaired and this may be contributing to the problem? A lot of other video bloggers use this yellow circle to aid their viewers to better follow their descriptions. Thanks in advance.
I really like this video and the last one! You should do more video's like this getting old broken things, dumpster diving and so on then show us how you fix the problem. Of course people will disagree with your methods but it would be nice to see you fix something you found. It is sad to see manufacturers only test parts like power, panel, or main board and if something is broken they just replace the whole thing! I mean you know yourself you could probably fix that board and it may be worth doing but its not always easy to diagnose. I remember back in the day we would have a tv repair man out and he would fix our tv and it would usually be something small like a resistor or transistor. but he would be there for quite some time with his kit finding the problem. You dont see that any more we need to see more of that though. Maybe not so easy on chips like you tried but at least some fault finding to repair something that would otherwise have been just dumped because its a repair the manufacturer either doesnt want to do or that the owners just go out and buy a new one. More like this please love it thank you!
I started the video, noticed you typed EEVblog, looked at the right picture and I am like: "Waaait a second, that's not Dave! And who the hell is Chris Gammell?!?" Bing ladies and gentlemen. Bing.
You’ve gotta get this thing working! Please do a part 2. I have the 55” model of this TV, so this is particularly interesting to me. Anyone know where to get that document?
On my older LG TV there is a way to drop into a human friendly built in debugger from the serial port. I can peek and poke registers. Maybe some of the same commands work. Some people even got as far as replacing the Linux kernel.
I'm going to send you some flux. You clearly do not have enough. :'(
Don't delay...
@Louis Rossmann : Don't delay, send it today :-)
Good advice from the Flux-Man himself!
He used about 1/10 of a Paul of flux
This job probably needs about 4 Paul's of flux since it's a bigger board and bigger chips
Don't give up, try reballing yourself, audience wanna see continuation Dave.
Looks like a job for paul to me!
Some people admire Elon Musk, I just admire people who are able to reball BGA chips on daily basis...
thats what i am going to comment.... 😁
Such a video might get banned… o.0
How does one reball oneself?
Amateur mistake, but no worries, I've done it too. Never poke huge BGAs like that when heated. The pin pitch is very small, and you're almost guaranteed to form solder bridges. Watch out for the board warping temporarily from heat too. That in itself can cause solder bridges to form, or it can cause other BGA chips to lose connections. The board needs to be supported so that it remains flat when heated. Flux will NOT "undo" solder bridges. The surface tension will keep them together due to the small pitch. As long as you didn't short power to data, no damage should be done. This is generally unlikely anyways since power and data pins tend to be far apart for integrity purposes.
It will have to be reballed. It's not difficult to do, unless the ball pattern is something particularly weird. Since you've killed it already, just heat+lift the chip and take a look at the underside (you can take tweezers with L-shaped ends, bend the tips slightly so that they grab onto the chip's edges, and this way you can lift evenly/vertically). Make sure you do so with minimum "pulling", since otherwise you can rip out pads. Measure pin pitch (since that's difficult, you can just measure the distance between 10 balls and divide - less error that way), order a cheap stencil from eBay along with some solder balls, get some proper BGA flux (I use Kingbo RMA-218 which works very well and doesn't stink) and watch some tutorials. :) Do this not because you need to or because it's financially sensible, but just to have the experience so that future situations become simpler to deal with. How can you be the #1 electronics blogger without at least some successful experience reballing chips. Come on Dave! :) :)
I +1 this.
Has he never seen @Louis Rossmann work ?
Dave says that he has fanned out huge BGA packages at Altium, then why does he ignore the known fact that the pitch is tiny ?
E: I think the attitude of "No script, No fear" is biting him in the arse.
Recently, on the calculator video, he was very mumbling. I think the reason for this could be
1. He wanted a quick video out, so did no do itsy bitsy research
2. He is moving the lab, it has occupied a lot of part of processing power of his brain...?
3. The power capacitors of his brain are now old and puffed, may need replacing ..🤣
Excellent advice. BGA rework is just hard! ;)
@@xMalhardeshmukh I'm pretty sure Louis and Dave know each other, and I assume they've seen each other's work (Louis has mentioned him before). Dave knew he made an error here and I'm sure he knows how to reball it, it's just something he probably hasn't done in a really long time so has apprehensions about it (and it's not easy unless you are well practised)
We can't do it ALL now can we. :) :)
Yes I know. that was sarcastic .@@schr4nz
When I worked at Nintendo at Kirkland, we had all the kit; Mantis microscopes, fancy Hakko soldering stations, air-pencils, vacuum rigs...you name it!
One bit of training they did was to allow folks to bring in dead consumer electronics with an eye at fixing them in the shop.
Get in a lot of practice working on other peoples mistakes!
A buddy brought in an LG TV, and over the course of 3 months every dang IC and transistor had been flowed off the PCB, cleaned, examined, put back on wrong, removed, broken, replaced, put back on right, you name it!
In the end it was a partly shorted by-pass capacitor...swollen electrolytic, nobody saw it!
Check yer basics first!
Working at Nintendo... I would love an old 2DS motherboard schematic... Have one here that doesn't power up (LED goes blue, stays few seconds, slight pop and turns off), can't find the fault to save my life. Not the screen having bad connection, nor screen itself (tested even with another 2DS screen).
That TV seems to have been molested way past repair point... Did you guys manage to fix it in the end or did all the molesting kill too many ICs inside to make it possible?
IT'S THE DECODE ENGINE RAM!!! It HAS to be either that or the decode engine in the main chip itself - thats where the signal is being blocked. The signal is fed from there to the [B] Engine block which handles the OSD etc and clearly is working fine. The decode engine and the [B] Engine have separate DDR3 controllers, so the ram fault isnt affecting it. The display output looks like classic VRAM issues. A RAM fault is also vastly more likely than a processor fault
Mijc Osis Yes... It is not even Samsung RAM..
nothing is being decoded when you play HDMI source
but yes it can be ram for en.wikipedia.org/wiki/XD_engine
Well even if it is the ram, now it has more than one fault, oops.
My thought as well, GUI memory/frame buffer is ok, but not the memory/frame buffer for the video decoder.
I was thinking the same. But now it's significantly harder to be sure.
Come on don't give up.
I'm not sure if your name falls between 3.11 and 95, or if it's still to come...
I think the issue is quite obvious: You didn't use enough flux! Check out Louis Rossman to see what an adequate amount of flux is.
Yeah you need at least one milliPaul of flux, that's like a microPaul or something. Totally inadequate.
Its 2 parts flux, 1 part PCB.
The bigger the glob, the better the job.
@The Dollar Guy
Is that by weight or by volume?
@Dave Micolichek pretty sure he doesn't get along with Louis Rossmann either :P
Service flow chart: Abnormal display ----> place in dumpster.
JohnAudioTech More great surface mount garbage, modern electronics is sure going down the $h!utter, no quality, hard to repair.
The right bga stencial solder paste and whit the stuff he have tv can be alive again or just ebay the pcb for like 50€ you can find the pcb and new tv.
IF the panel is ok the repair worth on 4 years old or less tv.
Then some guy comes along
"oh look, a tv. I wonder what's wrong with it ???"
@@scottb721 Or not, because if you're a nice person you'll write on it what's wrong with it!
or give to Dave Jones.
for those who don't know, chris gammell is his co-host for The Amp Hour, a podcast about electronics
@@Dead_Ringer They only recently met in real life, having done the podcast for years and years.
phones without ir blaster work just fine.
get the IR code as a pcm wav / audio file, hook up a ir or even red led to the 3.5mm jack (if you got one lol) and play the file. i entered my lg tv service menu this way many times.
Does it really have enough power and voltage to drive a LED? What can the jack do?
ur phone sucks my phone has ir
a red / ir one of course, their Vf is right at the peak of what a headphone jack can deliver (note: amplified headphone jack not just line-out which is just 1 Vpp).
the led isnt running at much power, a red one is barely lighting up but its enough for the sensitve ir receivers to detect it when holding it like 1cm infront. certainly less than what most headphones require.
link to a write up or something?
does phone amp has enough output power / frequency response at 38 KHz for IR ?
openlgtv.org.ru/wiki/index.php/Access_hidden_service_menus_/_modes#Simple_improvised_home_brew_IR_transmitter
Dave, would you like to go for another round, may be re-balling the chip. Don't give up
I'll cast another vote for a Dave Jones Loius Rossman shared universe! But yeah shipping between these countries is either super slow or super expensive.
COM port is for interfacing with an component controller. (Home automation type stuff.)
Ah, thanks.
and the protocol is an ask and answer type thing... so you have to know how to initiate comms!
Good to see Dave come a gutser every now and then. Makes me feel a little bit better.
Some initial tests for BGA would be applying pressure with your finger while TV is on and looking for any change in picture, cooling and or heating chip when TV is on looking for a change in picture. When attempting reflow look at near by soldered components for any solder melt which would indicate that the BGA is also melted instead of touching chip for movement.
It's the decoder RAM, because you have image movement, it's communicating but reading/writing wrong bits. But I think you toasted it, these operations must be temperature controlled
the instant he tapped that chip a little too hard, I was like "it's f**ked". good try tho. time to find a reball stencil
Well reflowing that chip, changed the output... So either you fixed something partly, or you just broke it completely and the error was actually before that chip, and because you broke it you didn't even get far enough to encounter the original problem.
Yes really want to see it alive and kicking again working 100%, don't give up !
Let me shed some light as to why the RS232 Codes are listed in the consumer manual. This is a former top of the line, home cinema TV. Most professional and home made installs for home cinemas work with universal remotes who send RS 232 codes via wire to devices such as the amplifier ,tv , screen and sometimes even curtains and such. Hence these are included because the consumer really does need them. I worked in a small scale cinema (1 screen) for about 5 years and we used this system.
Exactly. Well said.
Why, then, does it have built-in speakers that don't look removable?
That is a high spec tv and worth fixing being only a few years old and comparing it to current model tv's (4K res, 200hz refresh rate, LED localised dimming, decent built in sound for a tv), so even if you have to buy a whole board to get it going after a couple of vids of you trying to fix it with what you have it would be worth it. RRP was $4599.00 when it left the market, average sell under $4000.00. brand new main boards available on ebay for $588.00 and $22.00 postage from melbourne. probably sell it second hand for $1500 easy once fixed if you could not find a use for it at home. i am a video junkie and i also sell TV's for a living and I would be more than happy to have this as one of my tv's.
Reball it! You can listen to Tom Petty's "Re-balling" to pass the time while doing it.
Hi Dave. First thing, you should be using proper flux for reflow. Take Louis Rossmann's offer below (he knows well).
Second advice, warm the board to about 160-180C on pre-heater. It is most likely lead free solder there so you need to run it hot. When you get the solder flowing with the hot air gun, don't use maximum flow, it may blow some small components around it off. Third advice, never push down on the chip, instead, very carefully push the side to check if the solder is flowing. In this case I doubt the reflow could have fixed the issue. I'd suggest chip replacement or entire board, which you can buy used off eBay. Thanks for your videos, enjoyable! Best wishes!
I think you meant the video decoder. The encoder would be for recording stuff, decoding is what was to be done to view video encoded in codec x.
Aw, poor BGA has it's balls all mixed up now :(
Too bad shipping to the states would cost probably as much as the TV itself, I like the "ship it to Louis Rossmann" ideas. It'd probably be an interesting challenge for him..
Be careful with "not used before" flux. The little bottle of flux that i bought at an electronics store not too long ago IS CONDUCTIVE!
Sure, it's a couple kOhms but i don't want it between the gate and drain of a FET in a switching power supply. Little IC's don't like to be powered with 325V DC.
my money is on that black ram chip
thats racist!!!4444
Try putting the TV in "game mode" and see if it works. Game mode is made to reduce input lag by bypassing post-processing of the image. The game mode might bypass the defective video decoder section of the chip.
Now we definitively want to see you repair this TV ! Is like a personal challenge for you .:)
Those service manuals assume board swapping. The days of narrowing down a particular component because of the service manual are gone. You have to use your instincts. The original problem looks to be like a video codec problem - something probably related to MP4 video since the problem only occurs in video streams. So whatever chip handles the codec for MP4 - that would be my target.
That's *LEAD FREE* solder for ya!
Wow. LG being great.I guess you might have gotten this board to work if you had studied bit more before doing stuff for it. That garble pattern was oddly specific and might show up in troubleshooting of panels in general. I dont think reflow would have helped here.I also had few panels to fix a while ago. Could not do anything because the backlight crumbled into pieces when touched. Had no idea how to give it new light that'd match the panel.
Henri Tuhola Just seems like bad graphics RAM where the decoder / framebuffer is working.
I used to reflow BGA for phones, flux is a must, and the trick is to lightly bump the corner of the chip to know that it's reflow-ed properly
They include the serial commands in the consumer manual because they are used by AV system integrators to connect and control the display via a control system such as Extron, Crestron, AMX, Control4 etc. They wouldn't put it in the service manual since those are rarely shipped with the unit and are not always available online.
Dave would make a great video to see you trying to re-ball that chip. I think a lot of people would like to see too. These try to fix it videos are excellent.
99% it was a ram failure, not that chip.. but now who knows? Throw the board in the bin and buy a good used one, problem solved.
Cracked joints can usually by identified by applying pressure to the top of the BGA while its running. Look for the picture changing. Failing that try heating and cooling the BGAs one at a time while it's running. The expansion and contraction will often show intermittent faults, but also temporarily fix o/c joints by breaking through the oxide. The PCB vias under hot BGAs can often fail due to expansion and contraction, it's not always the solder joints. The DDR RAM chips can fail. We often have issues with them not going down properly in the first place because they're so light. We find the larger metal topped BGAs usually go down okay, but suffer more expansion contraction fractures longer term, so I always suspect the hotter running chips.
22:08 "so you gotta be looking carefully for it... so hopefully those joints get hot enough"
good one! got me to stop what I was doing and look at the screen.
Not sure if it works on the consumer models, but on the pro version on the LG screens you can enter the service menu with a regular remote.
Press and hold menu until the menu disappears, then press 0 (zero) 4 times and the set or OK button.
And if you have a samsung screen you turn it off, press mute 182 and power on, and the service menu should appear.
Be vary careful in the samsung service menu, you can actually brick the screen.
Here I am 2 years later, watching this EEVblog episode and RUclips break for commercials. The commercial was about LG OLED TV :D. What are the odds :p
Looks an awful lot like an GPU with failed GDDR so i would suspect the RAM of either U14 or URSA9
Always good to see things not going to plan
I don't see ads because ad blockers.
Do you have Adblock on the LG TV app?
That's great for your computer. But when you're watching RUclips on your phone or smart tv, that doesn't work. Most purple watch RUclips on their phone. Usually the only people who watch RUclips from a computer are people who work from home or don't have a job.
@Andrew Delashaw For mobile, use "RUclips Vanced". All the benefits of premium without having to pay google.
Watch some ads. It won’t hurt you!
@@xenonram I don't use the youtube app on my phone or tablet.
Ad blockers work on phone, tablets if you use a browser to access youtube. :)
Remove, clean the board with a solder wick, try wiping a thin layer of solder paste on the chip ( while it is upside down and alone ) to attempt to have it reball with out a stencil
I like how Dave only decides to do the right thing after he does it the wrong way. :P You needed the very liquidy flux to slide under the BGA from the start. And NOT TOUCH IT. And good use of Kapton tape at the end.
my first thought was the MPEG decoder is screwed...but it could possably be the RAM on either the main decoder chip or the U14 or URSA9 chips...looks like a PC graphics card with bad RAM...one of the RAM chips on URSA9 looks to have something on the top (notice you can read the other 3 fine)..the glue blobs maybe there to help keep the chips from lifting under heat stress..
but meh! its dead now!...send it to Louis to have it reballed..he seems to enjoy that crap!
That was my initial thought, one of the ddr3 modules (bga's) is likely toast. Perhaps the pair on the left in the illustration is the framebuffer memory. (the one marked with 16x2 lanes?) That said it could still be a power issue, the chip will consume more power the moment you play video and a PSU rail might be dropping.
"looks like a PC graphics card with bad RAM" was my 1st thought when i saw the 1st video.
Yeah, my bet is on the RAM... It is not even Samsung!
Adding to this the OSD would just be superimposed on the data before going to the LCD panel, so the chip you desoldered likely had little to do with the issue unless there was a problem with the input side of said chip.... you can see that the video selection and OSD is pristine so it would have been the main SoC that was decoding the video where the issue lied, and it didn't look to be the chip you ruined. Also you failed to do the tap test, tap, press, super cool via compressed air trick, bend various areas around the chips and see if symptoms differ... etc.
You can poke BGA chips. You also need to poke them when reflowing to make sure all the balls melted. What you should not do is apply pressure. Poke them from the side, with tweezers, and apply just a little tiny bit of force, just enough to make it move a bit.
Thanks for sharing Dave!
I ABSOLUTELY HATE BGA's !!! Since it was a dumpster dive unit I wouldn't have felt so bad if it had been me and I got the same results...though if you continued to work on it, and especially if you ever got it to work, I would love to see that video!!!!
Nicely done Mate. Thumbs up! You gave it a go. More than I woulda. Id a just changed the board.
excellent video, by the way. i love seeing your rationale and troubleshooting process. engineering is all about problem solving after all
Glad to see you gave it a shot.
stupid BGA's! Reball the sucker!
Thanks for the video as always! It feels nice to see I'm not the only one bodging up repairs like this. Can't win 'em all!
Great video as always Mr Gammell
I'm so much better than that Aussie dickhead!
@@EEVblog That's what you get for using Bing as your search engine, mate :D
Keep going Dave, we want to see it fixed!
Lets say this fault could be fixed by a successful reflow, would applying a force to the chips in turn help diagnose which is the culprit. I am assuming that it was once working and if it is a failed solder ball then it must only be a hairline fault and a small force would temporarily re-make the connection.
I wrote a script at work that uses the RS-232 on an LG TV to automate entering text on the keyboard. Also, on some models you can change Debug Status to "EVENT" (in the Instart menu) and it'll unlock all kinds of cool debugging menus if you type the word "debug" on the RS-232 terminal.
By the way, you should be able to simulate pressing the Instart button to open the service menu by sending "mc 01 fb" over the serial port. The password is 0413.
You need a unit with a smashed panel..Cheap
Not that cheap
unless he's really hurting for a TV, might be better to offer up his working panel on eBay for someone who has smashed theirs
Does Dave sell anything?
@@Sharklops imagine the postage price for this absolute unit
@@Sharklops Not sure how he calculates his cost per hour of work (for a RUclipsr it's likely: work as much as possible while fitting everything else in your schedule and receive a huge variation of revenue), but a few days of work is probably not worth the cost of a TV for him, unless he receives revenue greater than the value of his time spent on this. Not sure, but it doesn't seem like he would save any money by spending the time on it.
However, there's the fun factor and if he wasn't going to be productive anyways, then it's worth it! I would personally do it for two reasons. 1) I don't have a 4K TV at the moment and 2) there are times during the weekend where I don't want to be doing my job but don't mind working on a project.
it was only 784 ball chip. just reball and test :)
I can't wait for you to hit a million subs. You need a play button in your office!!!
9:00 32KBI$, 32KBD$, 1MB L2 $. That's creative. What I think happened is that because cash and cache are pronounced the same (at least in non-Aussie English) someone symbolized cache with a dollar sign.
@@Okurka. Interesting. Do you have a reference that using a dollar sign to denote cache is a common thing?
I've been there too and learned the leason. Once you poked that chip I remembered myself doing this on a friend's laptop (bought him a new laptop from my pocket).
dug a 55" Philips 4K out of the countys land fill on 1 of many TV rescues I do, the kicker was whoever chucked it actually taped the remote to he stands base as well... *BONUS* baby!!!.
The problem was ez-pz to rectify, just had to replace the LED backlights,.... all 52 of them. w00t!!
Shades of a repair I have done a couple of times on old PS3 following the “Gilksy guide”.
Preheating is a good idea, in my experience boards can warp unless the temp is raised around the chip. Also, I wouldn't consider reballing, if you're going down that path try and find a replacement chip and replace the part. I've only ever reballed my own hardware since they are hard to guarantee. Having said that, a great video as always, I always learn something new watching others troubleshooting steps.
The number 1 electronics blogger with zero repair acumen other than changing a few capacitors/voltage regulators
Great stuff doing the trouble shooting procedure. Really interesting watch.
I hope you attempt a BGA reball, even if all we learn is what not to do.
I would love to see you try to go down the rabbit hole.... Continue to try to fix it
my guess would have been something to do with hardware compositing which seems fairly correct given what you found
Hi Dave. Thank you for sharing this with us. You could have scrapped this edition and we would have been none the wiser. Instead, you chose to share it, "oops!" and all, and I applaud you for that. It takes courage and a strong sense of confidence to share mistakes with others, including the supercilious egomaniacs of the world who feel compelled to tell you how much better they would have handled this. I do hope their insensitive remarks don't offend you. Your videos are as educational as they are entertaining, and I thank you for sharing!
First of all - why should the chip move when you just heat it up? It was already completely centered when it had been reflow-soldered at the factory, so it will not jump around that much you can see. And 2nd suggestion: Never ever try to reflow completely without flux, because even if it will heat up properly the soldering connections will just get briddle and oxidized when heating up them again. No flowing activity will really happen without flux. Do like Louis (Rossmann) would do, flood it with flux gel and you will be fine... ;)
at 18:00 Dave mentions that the URSA9 chip had its heatsink already detached. he then turns the board around and at 19:10 there is a shot of the other side of the board under the chip with some discoloration - that chip was getting seriously hot while operating, which is not a good sign.
so i actually think that heatsink was not properly attached and without proper cooling the chip just cooked itself eventually.
I have done reballing on a few Xbox 360's and yeah it does take some getting used to. A lot of precision required. Its easy to put new balls on with the right stencil though. The hardest part IMO is making sure the chip is properly aligned. There might be tools to make that part easier as well.
I think they expose the serial interface easily and explain it in the user manual because there are commercial control units. For example in a commercial building where you want a tv that people can't mess with it or something.
Also, kapton can create 'ovens' where heat gets trapped and melts connectors instead of protecting them. Kapton can also move on you and pull all those nice parts off their pads.
No Dave! It could be the ram unit I mentioned earlier.
can you send the board to someone to reball? it's a nice TV, I think is worth. Please more troubleshoot-reverse engineering- repair videos, thanks!
Shipping cost would be too much to be worth it, unless it's a local place.
There is maybe somebody repairing phone pcbs anywhere near. They could reball it.
Dave: you, like all of us other techs, are the victim of the industry using Eco Solder. When they started using it, the temp that causes it to melt was lowered and now we have failures due to it. I try to use old lead based solder when I can as it has a higher temp to it. Keep up the good work my friend!
Time to call Louis Rossmann
Paul daniels is somewhat local and might venture outside the apple ecosystem.
to dump more flux on it!
Regarding the "use your phone" comment. There has been an app where you could use the audio output to drive an IR LED, you just had to add some 38kHz modulation behind it. Can't find it anymore though...
You should of tried freeze spray first. My guess...clock going out of lock. Some of the corrupted pictures made me kinda think that rather than data or address issue on RAM. Maybe broken power supply cap causing local supply dip. 4K means there are several GHz clocks probably coming from the HDMI chip interface even if nothing plugged in, it will probably fall back to locking to a local reference.
Pink screen remembers me old tv tuner card, program was drawing a pink area and tv tuner card overlaying image on that area. In my opinion Dave found problem on diagrams correctly.
Generally, you might hold a chip to be reflowed with a set of tweezers, and since you can't always be orthogonal to the chip it will move however slightly when the balls liquefy and then you know to let go and let cool. Tons of flux might have been appropriate as well.
(A total aside, separate is unlike most words with and ur sound in the middle [with an _er],_ but you know because separate has _a rat_ in the middle, lol! It's how I avoid misspelling it;)
Why _wouldn't_ you take it off and reball it? It isn't difficult and you'd teach people something. Is a replacement easily available for the chip? Reball and replace? You have a reball stencil right?
Totes realize that Australian spelling might be different than Yank spelling, lol!
Because:
a) This video is already 30 minuets long and valuable in it's own right, so upload now.
b) No I don't have a reballing stencil, and I have zero experience with reballing.
c) I have not looked, but I doubt a replacement chip is available.
d) What if some pads lift and/or something else goes wrong, it's a one-shot deal and I have zero happy ending to show in a video. It's not like I have any of these boards or chips to practice on.
So in this instance, no it's not easy to just go and re-ball it.
Patrick Horgan It's generally not the "rate" part that's hard to spell, except when the brain strain from the 1st half spills over.
@@johnfrancisdoe1563 I think he meant "a rat" in the middle but didn't italicise the first a :)
Chris Gammell of contextual electronics, I think he's on a pretty famous podcast...
I suppose it's easy come, easy go ..... The set didn't cost you anything and you learned something from trying to fix it (even if that something was just "don't move BGAs while the solder is molten"), so at least you haven't lost anything.
Of course, if you put that set back in the dumpster now you've bust it, another identical board is bound to turn up .....
i know its not what this channel is about, but in the real world, the best way to fix this would be to get a secondhand board, as there are so many tv's with cracked screens, there are normally plenty of spare board around on ebay. be a great tv once fixed ! :)
yes, I'd like to see you reballing this, it should be interesting!
If it aint broke, fix it until it is!
If you put a little flux around what you are trying to re-flow you can tell the chip has reseated because it dances. That's the point at which you stop heating. Also flux around the chip insures you don't have dry balls. Nobody likes dry balls during a re-flow.
I've been watching you for over 2 years and "REALLY love" trouble shooting things, (especially technology. I don't have a degree on tech but, I DO know how to troubleshoot a lot of things....
i think better than re-balling the chip,try searching aliexpress or ebay for a complete replacement board (used or refurbished one) will be cheap enough i think
What a complex circuit! Here I thought displaying a picture and playing some sound was a simple thing
That SysRQ message means it acts upon sysrq keys, so if you find a way to send it sysreq-h (for help) you might be able to see if it reacts on anything at all
I replaced a defective mainboard in one of these about 1.5 years ago, it was displaying a cycle of red/green/blue/white/black constantly and wouldn't respond. Board cost around $220 and I sold the TV for $1400, not bad.
I have never reflowed anything, but I would expect some things to be true of BGAs. The point is there are a large number of pads on the bottom of the bga and their associated solder balls. I'd expect if the bga moved sideways, for example if you blew air on it, it may short out solder balls, or glob them together in weird ways. I don't think it would be cool to see too much movement with the bga. Perhaps an IR temp sensor could just be used to see if it was hot enough. I have an AGP graphic card that went weird in the DVI but not vga one day and I wanted to maybe reflow it, but I don't want to screw up my cooking oven, and I would have to take the electrolytic off the board first??
Haha really enjoyed this video, great fun in the troubleshooting bit, shame the chip moved but I'm sure that can be fixed. That URSA9 looked like it was cooking in there, brown on the underside of the PCB!
Hi Dave, nothing to do with this video specifically, but, when describing things on your PC like the service manual for the 4K TV in this instance. Could you get one of those yellow circles that is superimposed on the arrow cursor to make it easier to follow it's movements on screen. You move it about very quickly and it is very difficult to follow. It may be just me, I am visually impaired and this may be contributing to the problem? A lot of other video bloggers use this yellow circle to aid their viewers to better follow their descriptions. Thanks in advance.
I really like this video and the last one! You should do more video's like this getting old broken things, dumpster diving and so on then show us how you fix the problem. Of course people will disagree with your methods but it would be nice to see you fix something you found. It is sad to see manufacturers only test parts like power, panel, or main board and if something is broken they just replace the whole thing! I mean you know yourself you could probably fix that board and it may be worth doing but its not always easy to diagnose.
I remember back in the day we would have a tv repair man out and he would fix our tv and it would usually be something small like a resistor or transistor. but he would be there for quite some time with his kit finding the problem. You dont see that any more we need to see more of that though. Maybe not so easy on chips like you tried but at least some fault finding to repair something that would otherwise have been just dumped because its a repair the manufacturer either doesnt want to do or that the owners just go out and buy a new one.
More like this please love it thank you!
I started the video, noticed you typed EEVblog, looked at the right picture and I am like: "Waaait a second, that's not Dave! And who the hell is Chris Gammell?!?"
Bing ladies and gentlemen. Bing.
You’ve gotta get this thing working! Please do a part 2. I have the 55” model of this TV, so this is particularly interesting to me. Anyone know where to get that document?
On my older LG TV there is a way to drop into a human friendly built in debugger from the serial port. I can peek and poke registers. Maybe some of the same commands work. Some people even got as far as replacing the Linux kernel.