Help Me Find What Capacitors on This Sony TV Power Board

altomic on 30/10/2018 - 17:26
Last edited 01/11/2018 - 14:03

I was given a 40" sony bravia tv -model KLV-40BX450

2 caps are blown on the power board - they are definitely blown.

I've identified them as CY1 + CY4 on the power board. (those are the markings next to the caps)

I've searched the interweb and haven't found the cap part numbers/capacities.

The power board/supply has DPS-166DP stamped it - which google shows is the board

part # 2950293507 is also given for board

Could someone with better internet search skills find what capacitiors are labelled CY1 & CY4 on the powerboard for a Sony Bravia KLV-40BX450 40" TV

thank you very much in advance.

edit - back from Jaycar - high voltage dIsc ceramic capitor 100pF 400v

part no. CD70-B2GA101KY

but they had none in stock. ebay, or online

thanks for the constructive comments.

Electrical & Electronics Sony TV

Comments

  • [Deactivated] on 30/10/2018 - 17:42

    The values are definitely not printed on the caps themselves?

    I replaced a few in an LG TV a few years back. I just desoldered from board and went to jaycar (as much as I hate them convenience won on the day). Soldered in news caps and bam.

    • altomic on 30/10/2018 - 18:24

      the writing is sooooo tiny. I can't make them out at all.

      • [Deactivated] on 30/10/2018 - 18:24

        Magnifying glasses?

        • altomic on 30/10/2018 - 18:26

          I think I may need a loupe. will go to Jaycar on thursday and get their assistance otherwise.

          • terrys on 31/10/2018 - 08:28

            @altomic: Or a close-up photo with a camera phone and expand…?

            • altomic on 31/10/2018 - 09:50

              @terrys: Good idea. Will try this after work

  • HighAndDry on 30/10/2018 - 17:46

    I make no claims about my Google-fu skills, but maybe some of these can help:

    Sony KLV-40BX450 Manuals

    Sony TV Repair-Part Number Identification Guide for Sony Main Boards-How to Fix Sony LCD/LED/Plasma from Oct 2012

    • altomic on 30/10/2018 - 18:28

      thanks -saw those. first link - page 37 - WD40 power board.

      it's just 2 caps that need replacing. cheers

  • geek001 on 30/10/2018 - 18:02

    I am guessing they are the cylindrical capacitors on the board. Usually the specs for those capacitors would be printed on the side of the capacitors.

    • altomic on 30/10/2018 - 18:30

      yeah no, not like regular caps. these are like a blue globe/ball shape - like this

      • Sergeant Salami on 30/10/2018 - 18:39

        If it helps, I'm pretty sure those types of capacitors are called "monolythic capacitors"

      • hawkeye on 30/10/2018 - 18:51

        varistor would be the first inline to blow.
        Getting close googling Varistor cy4

        • altomic on 30/10/2018 - 20:15

          that could be it. makes sense. hmmm

          • hawkeye on 30/10/2018 - 22:51

            @altomic: In your case it would be cheaper time and effort to replace the whole board unless you want to learn something and turn it into a hobby.
            Anyone who repairs things rip out the whole board and replace in a tv washing machine microwave ect to save chasing their tail.
            Who tries to repair a mainboard in a PC

            • altomic on 30/10/2018 - 23:17

              @hawkeye: I did a TAFE electronics course years ago. I'm comfortable troubleshooting and desoldering&soldering

              just couldn't find the part number. will go to Jaycar and get their assistance.

      • c64 on 30/10/2018 - 19:52

        they might not be caps but rather varistors (used for surge protection)

      • bluesky on 30/10/2018 - 20:45
        +4

        They are tantalum capacitors - generally around the 1-10 uF range. If the capacitors are blown, usually the voltage rails have gone too high - and the problem is probably due to something upstream (blown transistors or voltage regulators). Replacing these may not solve your problem.

        • kmwa on 31/10/2018 - 22:07

          I think bluesky is right. Varistors are normally disk-shaped, whereas tantalum capacitors are a round blobby shape https://www.jaycar.com.au/10uf-25vdc-tantalum-capacitor/p/RZ…
          You will need to know three things to fix them:
          The capacity in microfarads (written on them), could be 1,10 up to 100 uF.
          The voltage (written on them), usually 10/16/25/35 V
          The orientation for putting them in the board (denoted by a + sign on the capacitor, and usually on the board too).
          Worth trying to change them, they are pretty cheap.

          • altomic on 01/11/2018 - 14:03

            @kmwa: back from Jaycar - high voltage dIsc ceramic capitor 100pF 400v

            part no. CD70-B2GA101KY

            but they had none in stock. ebay, or online

            • bluesky on 01/11/2018 - 15:36

              @altomic: Hmmm … something is strange here. So, getting a bit curious.

              Generally, the 100pF capacitors are virtually indestructible. Their values are so small, and the voltage ratings so high (400V), that if they were to blow, everything else in the circuit board would have blown before they do. Have yet to see a blown 100pF capacitor in all these years. You can connect this capacitor on the 240V main rails and nothing will happen due to its voltage and capacitive ratings (note: people, don’t try this at home :-), unless you know what you are doing!)

              So small is the rating you can even make such a capacitor by twisting 2 very thin insulated wires together tightly. Although even smaller ones, like 39pF have their uses.

              If they are on the high-voltage side of the circuit board, and manage to blow, lots of other more susceptible parts would have blown first. Other than these caps, do you see evidence of other faulty parts like, bulged electrolytic capacitors? Have you checked out the transistors yet?

              Did you manage to expand the pic of the capacitor and see the rating? Any chance you can post the pic here? I am wondering because the first pic you posted is definitely a tantalum cap (since it is a stock picture, so could be a mistake).

              • altomic on 01/11/2018 - 18:01

                @bluesky: at jaycar they used one of the store electronic magnifying glasses to read the numbers so no picture.

                no other evidence of any damage. I checked pretty thoroughly, jaycar guy checked pretty thoroughly too.

                he might have read the numbers wrong….

                I can make out 222 on the cap. but that's about all. (my eye sight isn't great)

                • bluesky on 01/11/2018 - 18:12

                  @altomic: Oh well, good luck with it.

                  • altomic on 01/11/2018 - 18:16

                    @bluesky: cheers.

                    I've messaged sony to see if they have a schematic for the board - or at least the values for the capacitors.

                    also, I don't see any capacitprs with those values on aliexpress.

                    • bluesky on 01/11/2018 - 19:08

                      @altomic: Yes, best to check with Sony. Because if they are in fact ceramic 222 cap, the last number is the multiplier in this case - so 22 x (10**2) = 2200pF = 2.2nF. A big difference from 100pF that Jaycar said.

                      If it is 100pF, they would just put 100 (here, 3rd number is not multiplier - yeah, not always consistent protocol). Or 101 (which is also 100pF using the protocol).

  • hawkeye on 30/10/2018 - 18:14

    The TV is worth about $150 briefly looking on ebay. To buy the primary side your looking at over $65 which is a big risk outlay if it has already damaged the secondary side your down $65.
    https://www.aliexpress.com/item/free-shipping-for-KLV-40BX45…

    • altomic on 30/10/2018 - 18:25

      it's just the capacitors - nice burn mark on the underside of the board. TV went off during a thunder storm

      couple of caps should only be a few $ so worth replacing to see if that was the only damage.

  • Richardc on 30/10/2018 - 20:51

    Can you read the number off the good one? Looks like ceramic capacitor.

    • altomic on 31/10/2018 - 09:51

      The problem is the writing is so tiny

      • Richardc on 31/10/2018 - 15:05

        Bring to jaycar and let them try?

        • altomic on 31/10/2018 - 15:24

          my plan for tomorrow. cheers

      • westom on 31/10/2018 - 22:35
        +1

        Nobody can really define it from observation. Best is to trace out the circuit. (Better circuit tracers output less than .7 volts so as to not conduct through PN junctions.)

        Learn what adjacent parts are doing by defining how each is connected. If that does not provide an answer, then post the schematic. Then others can define a part and value based upon what a designer would do.

        It could be a tantalum meaning you must also learn which PC trace requires its plus lead.

        Furthermore, if that cap is destroyed, then a destructive current was also going through other parts. Lightning is a connection from a cloud to distant earthborn charges. It must have both an incoming and a completely different outgoing path through that board.

        Most, who never do what you are doing, do not know any of this. Kudos for attempting this repair. Since the biggest reason for repairing stuff is to learn.

        We may not have a correct value. But once the part is identified (without a value), then some other similar part (of a different value) can be used. Then we can learn if other parts are damaged. And eventually install the right part with correct (or better) values.

        It is rare for any electronic failure to have a visual indication. That destruction implies something else (just as simple to locate) is also damaged. Which one? What was the incoming and outgoing current path?

        • altomic on 01/11/2018 - 13:26

          was looking for the schematic - no luck.

          the damage wasn't very visible on the board. - just slight discolouration of the 4 solder joints for the 2 caps.

          it wasn't until I looked at the LCD backing (behind the power board) that I observed obvious heat discolouration.

          about to go to Jaycar.

          edit - back from Jaycar - high voltage dIsc ceramic capitor 100pF 400v

          part no. CD70-B2GA101KY

          but they had none in stock. ebay, or online

          • westom on 01/11/2018 - 22:43

            @altomic: Schematics are no longer available. As noted earlier, learn what adjacent parts are doing by defining how each is connected. If that does not provide an answer, then post a schematic that you created. That means a continuity tester - that works best when it is less than 0.7 volts. Therefore P-N junctions are not reported as a connection.

            Only better meters do that. Or continuity testing circuits (provided elsewhere).

            Electronic parts are best obtained from electronic supply houses (ie www.digikey.com.au)

            Is that an AC line filter? Trace that circuit and report that schematic. If an AC line filter, then it must be a special type capacitor.

  • mikekiwimike on 31/10/2018 - 07:58

    Good on you I have fixed a ASUS monitor by replacing the caps for $10 plus labour. Ebay surprisingly is where I found the cap kit I needed (because the ones that blow are fairly common).

  • theya on 31/10/2018 - 14:19

    would need to see the writing on the cap to tell you what it is.

    CY probably stands for a y class safety capacitor. ie a capacitor between line and ground. they come in classes 1-4

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