Announcement

Collapse
No announcement yet.

testing vizio L32hdtv10a

Collapse
X
Collapse
 
  • Page of 1
  • Filter
  • Time
  • Show
Clear All
new posts
Previous template Next
    #1

    testing vizio L32hdtv10a

    I have a vizio l32hdtv10a that doesn't turn on fully. i plug it in and without pushing the power button, the power light turns green. I also can't turn it off without unpluggin it. I have noticed that the remote 3.3v signal that turns the power supply on fully is not existant, it shows no voltage whatsoever. I have already pretty much determined that the main board is bad. What i'm really trying to figure out now is, 1. is my power supply working properly? and 2. is my lcd inverter board working properly? I tried supplying my own seperate 3.3v signal to the remote pin on the power supply. It seems to show healthy voltages on all pins. the 24v pins are showing proper voltage, the 5v pins are showing proper voltages, and the 12v pins show proper voltage. But my main question is, if i get power supply to turn on fully with everything hooked up properly, shouldn't the backlight atleast turn on? whether there is a faulty main board or not? or does the mainboard somehow control the backlight and let it turn on? I'm showing voltages going to the lcd inverter board but none of the lights are on, and only one half of the lcd inverter board seems to have power flowing. some help would be appreciated, i'm almost at my wits end with this thing. I don't want to have to order more parts than i need.
    Tags: None
    #2
    Re: testing vizio L32hdtv10a

    Originally posted by p_trice View Post
    I have a vizio l32hdtv10a that doesn't turn on fully. i plug it in and without pushing the power button, the power light turns green. I also can't turn it off without unpluggin it. I have noticed that the remote 3.3v signal that turns the power supply on fully is not existant, it shows no voltage whatsoever. I have already pretty much determined that the main board is bad. What i'm really trying to figure out now is, 1. is my power supply working properly? and 2. is my lcd inverter board working properly? I tried supplying my own seperate 3.3v signal to the remote pin on the power supply. It seems to show healthy voltages on all pins. the 24v pins are showing proper voltage, the 5v pins are showing proper voltages, and the 12v pins show proper voltage. But my main question is, if i get power supply to turn on fully with everything hooked up properly, shouldn't the backlight atleast turn on? whether there is a faulty main board or not? or does the mainboard somehow control the backlight and let it turn on? I'm showing voltages going to the lcd inverter board but none of the lights are on, and only one half of the lcd inverter board seems to have power flowing. some help would be appreciated, i'm almost at my wits end with this thing. I don't want to have to order more parts than i need.
    First, stop and take a breath once in a while. The single long paragraph is overwhelming.

    Next, pictures help us help you. A single picture taken from directly above the main board would be appreciated.

    Vizio had a problem with U33, a 1117 class (AS1117, LM1117, etc) LDO regulator on several of their TVs. Before you get too excited, see if there is a U33 on the main board. Your symptoms do not match exactly. Or I misread what you were trying to express in the flood of words.

    The inverter is controlled from the main board. Signals to turn it on and set the brightness are sent late in the start-up sequence.

    PlainBill
    For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

    Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

    Comment

      #3
      Re: testing vizio L32hdtv10a

      sry for the long paragraph, i was just trying to be descriptive and thorough about the problem i am having. I'm not sure where U33 is located on the main board. I have looked and looked but most of the letters and numbers are too small for me too read. I tried to attach a pic of main board but it won't upload for some reason. So your saying that the lcd inverter won't turn unless instructed by the main board or? So if i replace the main board, will the tv work properly again?

      Comment

        #4
        Re: testing vizio L32hdtv10a

        You know this is the 2nd time PlainBill and others have told you to check U33.

        From your previous thread ...

        https://www.badcaps.net/forum/showthread.php?t=17312

        Note the picture restrictions/instructions/limitations below.
        --- begin sig file ---

        If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

        We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

        Please do not post inline and offsite as they slow down the loading of pages.

        --- end sig file ---

        Comment

          #5
          Re: testing vizio L32hdtv10a

          i have looked and looked, i can't find U33. could someone point out to me where in this picture u33 is?
          Attached Files

          Comment

            #6
            Re: testing vizio L32hdtv10a

            Originally posted by p_trice View Post
            i have looked and looked, i can't find U33. could someone point out to me where in this picture u33 is?
            Not on that picture. I can barely count pins on the LDO regulator, let alone component IDs. You may have a different main board.

            If you look at the picture, near the top center is a symbol consisting of an interlinked LF (probably indicating Lead Free). Just below that symbol is some text, to the right of the text is an LDO regulator, it probably has a part number of AS1117. Note that pin 1 is on the bottom, the middle pin and the tab are identical. U33 (if it exists) will be identical to that. There is another IC in an identical package about 1/3 of the way up from the VGA input (blue) connector.

            With the main board and power supply screwed in place, the TV plugged into an AC outlet, and power on, measure the voltage on the three pics of each IC in an identical package. Report the results.

            PlainBill
            Last edited by PlainBill; 12-14-2011, 07:40 AM.
            For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

            Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

            Comment

              #7
              Re: testing vizio L32hdtv10a

              yea, my camera is kinda crappy. sry for the blurry pic. I tested with voltmeter and found no voltages whatsoever on any of the pins for the components u mentioned. And I am pretty much certain that this board has no U33. I looked for hours.

              Comment

                #8
                Re: testing vizio L32hdtv10a

                Originally posted by p_trice View Post
                yea, my camera is kinda crappy. sry for the blurry pic. I tested with voltmeter and found no voltages whatsoever on any of the pins for the components u mentioned. And I am pretty much certain that this board has no U33. I looked for hours.
                Have you checked for fuses on the main board?

                PlainBill
                For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

                Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

                Comment

                  #9
                  Re: testing vizio L32hdtv10a

                  yes, there is one fuse on the board. I checked it with a test light, it is in working order.

                  Comment

                    #10
                    Re: testing vizio L32hdtv10a

                    Originally posted by p_trice View Post
                    yes, there is one fuse on the board. I checked it with a test light, it is in working order.
                    Then without better quality pictures I can only suggest you buy a replacement main board.

                    PlainBill
                    For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

                    Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

                    Comment

                    Previous template Next
                    Working...
                    X