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    #41
    Re: old Bravia double fail?

    test is also to see if the proper voltage is getting to and from the fuse.

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      #42
      Re: old Bravia double fail?

      results of test in post 36? I will very seldom ask for a test that is not needed, every test gets you closer to the problem, remote no see troubleshooting is very difficult and needs to be done in order, as in test one done here is result then we can move on, these thing require work, if you dont want to test, how will you get the answer to the problem.

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        #43
        Re: old Bravia double fail?

        guess I'll give up at this point, some others here may be better suited to help on this issue.
        Last edited by nomoresonys; 12-17-2022, 07:05 AM.

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          #44
          Re: old Bravia double fail?

          Those flex cables ... I'm really hesitant on touching, worked on them in the past and the slightest stare at them have always made the problem worse so I'm leery of touching them until it comes to that time when it's really suspect. At this point due to the "double fail" issue I can't suspect that yet -- all of the photos I've seen online of the vertical line issues involve some sort of background picture faintly showing ... now that would clearly be some sort of tcon issue.

          So far the data collected:
          - Power switch and remote control can turn on/off the power supply. Inrush relay clicks. Green power LED accurately shows power status
          - 12V and 24V supplies are up when the power is pressed. 3v3 always on is working.
          - There is NO fail red LED blink codes on the standby LED
          - The SPDIF LED only briefly flashes on poweroff only, else it's always off.
          - Attempting firmware update, the USB stick activity LED only blinks once and stops on poweron.
          - Backlight inverter is working as witnessed by forcing it on - appears to be an active high signal that the microcontroller needs to set.
          - Backlight is supposed to feed back an error signal if it fails to come on that notifies the microcontroller
          - The inverter output pin of the microcontroller never turns on/goes high and thus the backlight will not turn on.

          This is all leaning to the microcontroller not running its code for whatever reason, however I'm not sure how much of the microcontroller is needed to turn the set on and off as I suspect the remote control somewhat uses the CPU, at least the always on section. Unless somehow the tcon to panel straps feed back to the microcontroller? I suspect the LVDS cable could feed back and tell there is a problem communicating to the panel but are these Sonys smart enough to notice there's a panel strap issue and simply not turn on if this is the case... and why wouldn't there be an LED error code for this situation?

          In any case microcontroller failure is a hard failure to fix, it's a #%*&#ing BGA. I'm thinking about scoping the data pins to see if there's any activity but what sucks is that the DDR chip is underneath the heatsink and I'll need to find some other pin to probe...

          The question I have is if I pull the panel to tcon straps, what should I expect... one half of the display goes blank, and the SPDIF LED turns on? Should I see the logo magically come up with it disconnected upon powerup? Just thinking about what each step does and what it's supposed to tell me... I wish there was a way to force something to show on the screen but it all depends on the microcontroller at this point after finally being able to force the backlight on.

          Actually I should probe the LVDS cable to see whether something is being transmitted to the tcon... Aha! That's my next step...
          Last edited by eccerr0r; 12-17-2022, 09:20 AM.

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            #45
            Re: old Bravia double fail?

            They are delicate but they should be ok as long as your not constantly messing with them, plus sometimes cleaning and reseating can cure lines on the screen, as when it's just dirty contacts or improper alignment.

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              #46
              Re: old Bravia double fail?

              ugh. if I need to end up getting a whole mainboard, seems these are unobtanium now, at least cheaply.

              Doomed to be a failure? *sigh*

              Wonder what the failure rate of these boards are for these TVs at least?

              Comment


                #47
                Re: old Bravia double fail?

                not very cheap, saw a few around 80 bucks or so.

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                  #48
                  Re: old Bravia double fail?

                  $80 is sure close to buying a new TV...

                  Comment


                    #49
                    Re: old Bravia double fail?

                    complete sony bravias much less money ..
                    https://www.ebay.co.uk/sch/i.html?_f...rt=nc&LH_BIN=1

                    Comment


                      #50
                      Re: old Bravia double fail?

                      Yeah looks like board swap is not worth it (though shipping a TV makes buying a complete set is not worth it either). Need to see if the board is repairable or not...

                      Comment


                        #51
                        Re: old Bravia double fail?

                        Anyone have comments about repairing these mainboards or do most people just swap boards? Pretty much the same as dead video cards?

                        Judging from the firmware image, this TV runs Linux, alas no networking...

                        Comment


                          #52
                          Re: old Bravia double fail?

                          In the spirit of
                          topic 112596 (photographing PCBs) I tried taking pictures of the BM3 board with three cameras... my crappy cell phone, a P&S, and my DSLR with my telephoto lens (not the kit lens).

                          Which is which...

                          And the $80 question, what is wrong with the board so I can use the TV to inspect the images? (ha. Well, I'd be quite shocked if someone figures out what's wrong by looking at the picture...)
                          Attached Files

                          Comment


                            #53
                            Re: old Bravia double fail?

                            Cell phone:
                            https://www.badcaps.net/forum/attach...8&d=1671532058

                            P&S:
                            https://www.badcaps.net/forum/attach...0&d=1671532058

                            DSLR:
                            https://www.badcaps.net/forum/attach...9&d=1671532058

                            ... though I can't say I'm 100% sure about the P&S and DSLR not being the other way around.
                            ------------------------------

                            Anyways, regarding the issues...

                            I haven't looked at the SM, but does the TV have some kind of a AC detection or power good signal that goes from the PSU board to the logic board. If it does and it's missing, the logic board could just be "hung" in the waiting state.

                            On the logic/mainboard, can we assume you've checked all of the fuses on there. I see quite a number of them. If yes, another item to check are all of the voltage rails from various buck and linear regulators, both with TV powered up and in STBY mode. If the SM lists the voltages, check that they are in spec with that (and with your scope, maybe check ripple too.)

                            Since the inverter isn't turning On properly and the t-con is showing garbage / vertical lines when you did force the inverter On, I can only suspect the logic/mainboard is not working at this point, and everything else is likely OK.

                            If all voltages on the mainboard are good, check some of the protection diodes on the HDMI and other input ports. If there are any that appear shorted or bad, that could be an indication the TV got "zapped" from something.

                            You could also just try a "lazy reflow" with a heatgun and hope that this is the issue and that the heating "fixes" it.

                            In any case... $80 for a (I presume) used mainboard? WTF are eBay sellers smoking these days?! If it is indeed a used board, I can bet my ass the "seller" (read: e-scrapper) took it out of a TV with a busted LCD for free. Expecting to make $80 from a scrapped part is ridiculous.

                            On a side note, I have a Sony KDL-40XBR2 that I picked up from CL last year for free. It's from a really old 1080p Sony LCD, but I wonder if it has compatible LVDS signals. If yes, perhaps the two of us could assemble one complete set somehow? In the case of my KDL-40XBR2, the guy on Craiglist listed it as "not working" (that was it) and free. Little did I know I'd be wasting time picking up a TV with a busted LCD (well, it's a tiny hairline crack on the screen only visible when the TV is turned On.) Otherwise everything else works.

                            At least the PSU is of Sony quality - all Japanese caps everywhere. Probably the only worthwhile part in there. Maybe the inverter and CCFLs too, if I can get them and transfer them to another TV of mine - a Samsung LN46b530p7f that keeps clicking On and Off. Everything on that one works, except the inverter, regardless if I try to force it On or not. And I can't determine if it's a CCFL issue, inverter balancer board, or inverter board. I posed about it somewhere in the forums a while back. Was going to convert it to LEDs using cheap LED strips, but the idea never took off due to some technicalities and also other projects. Wonder if I can cobble that Sammy TV with the PSU, inverter, and CCFLs from the Sony. Gonna be a massive hackjob, for sure.

                            Anyways, sorry for the off-topic in your thread. I'm just thinking out loud like you. So many TVs with seemingly small issues... yet so far from being working units.

                            Comment


                              #54
                              Re: old Bravia double fail?

                              Comments are always appreciated, could always find something new that was missed. That powergood signal is actually something I hadn't considered, will have to go look for it.

                              BTW you're right about the photos, good job! I thought I might throw someone off due to the soft focus of the telephoto lens but it does make sense why focus might be off - it may not really be focus but shutter speed too low. Next I'll have to try to get a *really* good DSLR picture that I spend the effort to get a good photograph that actually exceeds of the P&S.

                              Also I love the P&S, it's a Canon Elph. Other than the fixed aperture, it has far exceeded my expectations for its lens and capture capability, and by far most of the photographs I post on BCN are from the Elph (if it wasn't from the even older Powershot which was one of the last few P&S cameras that have variable aperture - and that too generated really good pictures before its sensor croaked). I don't think I posted many pictures from my DSLR manly due to the fact the powershot and the elph are so much more convenient to grab.
                              Last edited by eccerr0r; 01-04-2023, 10:26 PM.

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                                #55
                                Re: old Bravia double fail?

                                You know, something doesn't seem right here.

                                A whole bunch of these TVs' main boards look *very* similar to each other, I wonder what the cross-compatibility is.

                                Also the other thing: all of them are $ARM$LEG ... do people charge by the apparent complexity of the board or true value of the board as a fraction of the value of the complete unit?

                                Things are not looking good for me getting another board for less than the cost of getting a complete working TV...

                                LOL https://www.badcaps.net/forum/showthread.php?t=36482 *sigh*
                                Last edited by eccerr0r; 01-08-2023, 01:19 AM.

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                                  #56
                                  Re: old Bravia double fail?

                                  The people that put a high price on these boards will be tripping over them and storing them for a very long time.

                                  Comment


                                    #57
                                    Re: old Bravia double fail?

                                    LOL, thanks for the words of encouragement. Alas I'm also hesitant on buying them as it seems the kind of failure seen is not completely uncommon/one off... wonder what the chances of another failure of the same type will happen again, not counting failure of tcon/tubes/panel...

                                    Comment


                                      #58
                                      Re: old Bravia double fail?

                                      very good question, once I found and installed the firmware that fixed my old 2009 sony, it was used quite a bit in lounge room from 2014-2020 when went with a bigger screen but still have it, I think it has a very good picture nice bright whites and pretty decent darks. Had very few problems, I did have I think a heat related problem, found out it ran fine with the back off so I just mounted it on the wall with back cover off. I think the older ccfl tv have been the most reliable tvs I have seen, except of course for the old crt tv's that are really hard to kill, with the prices they want if I did buy a board, I would get it from a trusted seller that will let you return it if it doesn't solve your issue, I wouldn't expect the seller to pay return shipping naturally.

                                      Comment


                                        #59
                                        Re: old Bravia double fail?

                                        Originally posted by eccerr0r View Post
                                        Alas I'm also hesitant on buying them as it seems the kind of failure seen is not completely uncommon/one off... wonder what the chances of another failure of the same type will happen again, not counting failure of tcon/tubes/panel...
                                        Funny you mention this. I just saw a posting on my local Craigslist for a Sony Bravia KDL-46W4100 that might have similar issues. According to the poster, "there's a problem with the timing band creating vertical bands in the display." Not sure what that means, though. The picture of the screen does look OK. Here's the ad if you're curious:
                                        https://washingtondc.craigslist.org/...568950143.html

                                        I looked at pictures of the main board for that model, but it looks different from yours. So probably not compatible with your set, I would assume.

                                        There's several other free TVs on my local CL, but I don't think I need to get anymore at this point. If anything, I need to clear the ones I already have.
                                        Just worked on a TCL 55" today that looks like I'll have to tear apart after all and replace the LEDs. Hopefully I don't crack the screen in the process, it's a very fragile TV. Wish me luck.

                                        Originally posted by eccerr0r View Post
                                        You know, something doesn't seem right here.

                                        A whole bunch of these TVs' main boards look *very* similar to each other, I wonder what the cross-compatibility is.
                                        Probably anywhere from completely compatible to not compatible at all.

                                        In the case of a Dell U2412Mb monitor I fixed last year, I got a board that was for the same monitor model, but just a few revisions newer. Everything on the board looked exactly the same as the original, at least visually. But functionally, it wasn't. Found a thread on here of someone who went through the same issue and managed to get the newer board working by noting that a bunch of SMD parts were different between the two revisions. Switching these made my board work too.

                                        So even if you do find a board that looks compatible / same, you would probably need to compare everything very carefully, SMD by SMD, to make sure something isn't different.

                                        Originally posted by eccerr0r View Post
                                        Also the other thing: all of them are $ARM$LEG ... do people charge by the apparent complexity of the board or true value of the board as a fraction of the value of the complete unit?
                                        I think it's a little more random than that.

                                        Some sellers will literally be tripping over this stuff, as nomoresonys mentioned, yet never drop the price to get anything moving/sold (and they can know how often and how many people look at their auctions, as there are counters for this.)

                                        Then there's the sellers who look if anyone else is offering the same board or not... and if not, they put a silly high price. Now, I can understand that practice if, like you say, it's for a TV set that is worth a lot of $$. But for a cheap/free old CCFL TV, it makes no sense at all. Moreover, $10-$20 here on my local Craigslist can often get me a complete working 40-50" LCD TV with remote and stand (not all the time, but such listings have popped up more and more frequently in the last 2-3 years.) It's to the point where I even ignore them now.

                                        Originally posted by eccerr0r View Post
                                        Things are not looking good for me getting another board for less than the cost of getting a complete working TV...
                                        In that case, just keep the TV for parts until a cheap main board does pop up.

                                        Alternatively, maybe you can try selling any of the working parts from your TV??

                                        I understand the frustration, though - you have a good screen/matrix, and you seem just that close to fixing the issue. For this same reason, I'm now very happy when I see a TV with a busted screen, because I know that if I do get it, I can just scavenge the boards out of it and chuck the rest. (Though, I've yet to do that with a few sets that are sitting outside. One has a nice metal shell that I'm thinking of cutting up and making a PC case with it, as I have a few motherboards with trays that don't fit well into ATX/mATX cases and could use something more "custom". )

                                        Originally posted by eccerr0r View Post
                                        BTW you're right about the photos, good job! I thought I might throw someone off due to the soft focus of the telephoto lens but it does make sense why focus might be off - it may not really be focus but shutter speed too low.
                                        Thanks.

                                        I actually had a bit of doubts between the P&S and DSLR photos, but the out-of-focus text on the bottom-right suggested that one should be the telephoto, since with telephoto, once the focus is locked at a certain distance, everything else that is further or closer to that distance will look more blurry. With the P&S, the focus is more "averaged" (please excuse me if I don't use the correct terms, as I never properly educated myself on photography), but still very crisp.

                                        And the phone one was easy to pick out, because, like most phone cameras, the image "details" are just simply not there, regardless of how high or low you set the resolution... though, to be precise, phones these days generally do a pretty good job of taking up-close / macro pictures. Still, there's no replacement for a proper lens. Otherwise, everyone could become a photographer with their phone and DSLRs would seize to exist.

                                        Originally posted by eccerr0r View Post
                                        Also I love the P&S, it's a Canon Elph. Other than the fixed aperture, it has far exceeded my expectations for its lens and capture capability, and by far most of the photographs I post on BCN are from the Elph (if it wasn't from the even older Powershot which was one of the last few P&S cameras that have variable aperture - and that too generated really good pictures before its sensor croaked).
                                        You know, I'm a big fan of the (older) Canon P&S myself. I can always tell them apart by their more crisp image and natural colors, compared to other makes.

                                        Most of the photos I have posted on BCN come from my now-22-YO-hand-me-down PowerShot A20. It's capable of capturing whopping 2.1 MEGApixels worth of imagery. And on a good day, it can still beat a modern phone camera, especially when it comes to taking pictures of things "far away". What's funny is that most of the time, I don't even use its full 2.1 MP capability, but rather only take pictures in 1024x768 or 640x480 and with "Normal" compression (Normal, being the lowest setting) - this mostly due to only having a 64 MB CF card. But it takes surprisingly good photos, now that I've learned all of its in-and-outs.

                                        Lately, though, I've been taking a lot of pictures with my phones, especially macro shots of electronics. Again, it seems that phones do a pretty decent job with close-up objects, especially very very close-up macros. In contrast, I need to "cheat" a little if I want to get such good macro shots with my PS A20 by putting a large 4" magnifying glass in front of its lens... and even then, the resolution is often too low to catch the writing/numbers on small SMD resistors. My newer phone's camera, on the other hand, can catch those pretty easily without any "cheating". And if I do use the magnifying lens with it, I can get the camera to focus literally right up to the surface of the component.

                                        The downside of the phone pictures is that I have to process them - they are often too large in size (both pixel-wise and disk-space-wise.) I find that many phones also don't add much (if any) JPEG compression to the photos... which is silly, because most phone pics I've seen have terrible details, regardless of the resolution. So using higher JPEG compression doesn't even affect the image quality most of the time, unless some ultra-high compression is used. On medium compression, I can often reduce the disk size by 3-4 times without affecting the image quality at all. Going from 5 MB per photo to 1.x MB is considerable when you start taking a lot of pictures. And if I cut/crop & resize (which I do), I can get that down to 200-500 KB (i.e. another 2-4x reduction in disk size.)

                                        Anyways, sorry for the camera off-topic stuff here.
                                        Last edited by momaka; 01-09-2023, 08:06 PM.

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                                          #60
                                          Re: old Bravia double fail?

                                          Yeah I think that W4100 has some tcon problem most likely and is unfortunately not compatible with the S5100.

                                          The thing that grinds my gears is that some of the mainboards for off brand TVs, people do try to sell cheap -- seems specifically Sony boards are expensive, however old Sony complete TVs are no more expensive than off brand TVs...

                                          That, and beyond that, I don't know for sure if I also have tcon issues without having a mainboard supplying proper data to the tcon to see what the panel looks like. Ugh. "Double Fail" or not... My panel at least *seems* to be good but I can't assume it until I get that mainboard
                                          Last edited by eccerr0r; 01-09-2023, 08:31 PM.

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