Announcement

Collapse
No announcement yet.

hyundai no image

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    hyundai no image

    got a hyundai l70n monitor that the power led will come on green and if you look closely you can see the screen flash ever so slightly (once per powerup).

    after about 30 seconds of the green light on, it will make a slight buzz sound and flash off. then it comes back on and the screen flashes ever so slightly.

    no bulging caps, can get pictures of front and back of the boards if needed.
    ordered an esr meter, but i'm not convinced this is a capacitor problem.

    #2
    Re: hyundai no image

    foto's of the invertor board pls.

    it sounds like a backlight problem of some sort.

    Comment


      #3
      Re: hyundai no image

      Attached is front and back of both inverter board and logic board.
      hope they are good enough quality, had the settings amiss on my camera, came out super dark and had to brighten up.
      Attached Files

      Comment


        #4
        Re: hyundai no image

        on the invertor/psu board:
        optoisolator pc101 looks like it went up in flames!
        and there is a huge amount of cracked solder joints on both boards.

        Comment


          #5
          Re: hyundai no image

          so in other words there is no hope for the monitor?

          Comment


            #6
            Re: hyundai no image

            pc101 looks burnt = you need to tell us if it is it is a common part easy to replce

            Solder joints can be reflowed if you can handle a soldering iron.

            So dependson how much effort you want to put in - there may be other faults.

            On the back in the centre about an inch up what is on the board next to the description
            zd181

            If you decide to scrap it offer it on freecycle as someone may need the parts

            How did it go with the westinghouse - hang on to this -might help with the other
            Last edited by selldoor; 07-19-2014, 09:07 AM.
            Please upload pictures using attachment function when ask for help on the repair
            http://www.badcaps.net/forum/showthread.php?t=39740

            Comment


              #7
              Re: hyundai no image

              Originally posted by selldoor View Post
              pc101 looks burnt = you need to tell us if it is it is a common part easy to replce
              pc101 is a L0436 817b y

              Originally posted by selldoor View Post
              Solder joints can be reflowed if you can handle a soldering iron.
              i hope so, made me a little fm transmitter on a pre-drilled board

              Originally posted by selldoor View Post
              On the back in the centre about an inch up what is on the board next to the description
              zd181
              ... a tiny black box that looks like zd103 and q105. dont know what it is though. doesnt seem to have any markings, but i dont have a telescope to check closer.

              Originally posted by selldoor View Post
              If you decide to scrap it offer it on freecycle as someone may need the parts

              How did it go with the westinghouse - hang on to this -might help with the other
              which westinghouse? the tv or the monitor. i replaced a bulged cap in the monitor and it came right on, although i notice some pixels are slightly darker, but only within a certain brightness range???

              waiting on my mesr to come in so i can check the caps on the tv. and i plan to keep the monitor for parts if indeed it is beyond repair.

              Comment


                #8
                Re: hyundai no image

                Still havent told us if the PC101 is really burnt - cant be too bad if you can read the number. see here to test it http://preher-tech.com/documents/optoisolators

                ZD - likely to be a zener diode just couldnt make into the usual shape of a zener.

                Westinghouse Monitor - I know it was only a " which capacitor" type thread but its nice to see some closure.

                Westinghouse TV - not seen that thread I think you have probably despatched it.
                12 volts into the blon - Its only meant to be 3v ?
                Please upload pictures using attachment function when ask for help on the repair
                http://www.badcaps.net/forum/showthread.php?t=39740

                Comment


                  #9
                  Re: hyundai no image

                  the optoisolator part number from what you posted is type 817b
                  the other numbers are the manufacturing date.

                  Comment


                    #10
                    Re: hyundai no image

                    What DC voltages do get on those filter caps on the bottom right of the board? I doubt that the Opto is bad, it is used for feedback to regulate the output voltages. If you do have 5V and 12V then the opto is OK.
                    If I troubleshoot this monitor, I will use test lamps to find out if I have inverter board problem or backlights problem.
                    Last edited by budm; 07-19-2014, 07:34 PM.
                    Never stop learning
                    Basic LCD TV and Monitor troubleshooting guides.
                    http://www.badcaps.net/forum/showthr...956#post305956

                    Voltage Regulator (LDO) testing:
                    http://www.badcaps.net/forum/showthr...999#post300999

                    Inverter testing using old CFL:
                    http://www.badcaps.net/forum/showthr...er+testing+cfl

                    Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                    http://s807.photobucket.com/user/budm/library/

                    TV Factory reset codes listing:
                    http://www.badcaps.net/forum/showthread.php?t=24809

                    Comment


                      #11
                      Re: hyundai no image

                      Originally posted by selldoor View Post
                      Still havent told us if the PC101 is really burnt - cant be too bad if you can read the number. see here to test it http://preher-tech.com/documents/optoisolators
                      i took the opto off the board and checked using methods 1 and 2. i cant get any ohms (infinite) on the emittor/collector side. using my dmm to emitter/collector and analogue to anode and cathode.

                      Comment


                        #12
                        Re: hyundai no image

                        " using my dmm to emitter/collector and analogue to anode and cathode." How do you have the analog meter connected to the LED side, which probe of you analog meter has positive polarity, the red or the black probe, and your analog meter may not have voltage or current to provide forward bias to turn on the LED inside the Opto. Did you verify that you you do have 5V and 12V on those filter caps, if the opto is bad you will no longer have regulation for the circuit to maintain 5V/12V output.
                        Never stop learning
                        Basic LCD TV and Monitor troubleshooting guides.
                        http://www.badcaps.net/forum/showthr...956#post305956

                        Voltage Regulator (LDO) testing:
                        http://www.badcaps.net/forum/showthr...999#post300999

                        Inverter testing using old CFL:
                        http://www.badcaps.net/forum/showthr...er+testing+cfl

                        Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                        http://s807.photobucket.com/user/budm/library/

                        TV Factory reset codes listing:
                        http://www.badcaps.net/forum/showthread.php?t=24809

                        Comment


                          #13
                          Re: hyundai no image

                          i would seriously recommend you DONT power that monitor up till you resolder all the joints that look cracked or have a visible shadow-ring around them!

                          Comment


                            #14
                            Re: hyundai no image

                            Hi all, i don't think the look of that opto tend to bad since there's no brown around it on the pcb, the dirt on it can be a laquer/flux residue, very common on pcb's.. stj i don't see any cracked joint, Jason you can measure high voltage transformers outputs in ohm and compare them or report here, test also those 2 8pin ICs on the back as mosfets or doublemosfets for shorts (chek first their datasheet). If you don't understand make a turn on this message board you can fast learn something more.

                            Comment


                              #15
                              Re: hyundai no image

                              Originally posted by Davi.p View Post
                              Hi all, i don't think the look of that opto tend to bad since there's no brown around it on the pcb,
                              the pcb wont brown if it goes fast because of something else.

                              Originally posted by Davi.p View Post
                              stj i don't see any cracked joint,
                              there are loads of cracked joints on both boards - look again!
                              specially on connectors and large parts like transformers.

                              Comment


                                #16
                                Re: hyundai no image

                                OK may have got sidetracked with the opto but not ruled out as a problem
                                Try this
                                No power to the board Meter on Ohms 2000 test S1 to S2 and S3 to S4
                                as marked on pic
                                Attached Files
                                Please upload pictures using attachment function when ask for help on the repair
                                http://www.badcaps.net/forum/showthread.php?t=39740

                                Comment


                                  #17
                                  Re: hyundai no image

                                  On power board i see 5-6 only suspectable dry joints in the psu primary zone, a picture like this can be clear enough due to reflections and shadows..
                                  Last edited by Davi.p; 07-27-2014, 06:05 AM.

                                  Comment


                                    #18
                                    Re: hyundai no image

                                    i must have a better monitor and video-driver/renderer.

                                    Comment


                                      #19
                                      Re: hyundai no image

                                      Resolder the joints and see if it will stop buzzing and the lamps stay on, if not, check the transformer resistance to see they are within the range of each other. I think its time to use the test lamps, otherwise you can spend lots of time on the board if the problem is the bad lamps, buzzing sound can come from bad wiring at the end of the lamps.
                                      Never stop learning
                                      Basic LCD TV and Monitor troubleshooting guides.
                                      http://www.badcaps.net/forum/showthr...956#post305956

                                      Voltage Regulator (LDO) testing:
                                      http://www.badcaps.net/forum/showthr...999#post300999

                                      Inverter testing using old CFL:
                                      http://www.badcaps.net/forum/showthr...er+testing+cfl

                                      Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                                      http://s807.photobucket.com/user/budm/library/

                                      TV Factory reset codes listing:
                                      http://www.badcaps.net/forum/showthread.php?t=24809

                                      Comment


                                        #20
                                        Re: hyundai no image

                                        i can confirm the opto is not bad. i had another one i found in an old tv. and i did the analogue and dmm testing method on that pdf. analogue was getting around 10 ohms and dmm got 43k, for both.

                                        i'll resolder some of the joints and check resistance and let you know.

                                        Comment

                                        Working...
                                        X