RCA LED46C45RQ backlight but no picture

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  • dynikus
    New Member
    • Mar 2016
    • 7
    • United States

    #1

    RCA LED46C45RQ backlight but no picture

    Hey guys, so my neighbor gave me an RCA LED tv, but there's no picture when I turn it on. I've tried some googlefu to find out what the problem most likely is, and everywhere said it's most likely the t-con board, so I ordered a new one and made sure the part numbers matched, but it didn't fix the problem.
    As far as I can tell, there aren't any blown capacitors on any of the boards, and the fuse on both the new and old t-con seem good, so I'm not sure what I should check next.
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    Last edited by dynikus; 03-05-2016, 10:41 PM.
  • CapLeaker
    Leaking Member
    • Dec 2014
    • 8034
    • Canada

    #2
    Re: RCA LED46C45RQ backlight but no picture

    there are a few things you can do:
    Check that you have power on both sides of the fuse on the TCon. Unplug one of the ribbon cables between TCon and the LCD panel, turn the TV on and see what happens. Then do the other side.
    Get an oscilloscope and probe the LVDS while turning on and off the menu all the time, or risk buying a new main board, hoping the LCD is good.
    Then you could "freeze" the eeprom on the main board (can of air upside down) and turn the set on. Check if there is a replacement eeprom available at SJ (there is). Make sure that your symptom is noted there.

    Comment

    • dynikus
      New Member
      • Mar 2016
      • 7
      • United States

      #3
      Re: RCA LED46C45RQ backlight but no picture

      Voltage is the same on both sides of the fuse. I didn't notice anything happen when either ribbon cable was unplugged.
      Don't have an oscilloscope and don't think I'll be buying one, but would it be plausible that the LVDS cable is bad? or would the problem most likely be with the main board?
      and what does freezing the eeprom do?

      Comment

      • CapLeaker
        Leaking Member
        • Dec 2014
        • 8034
        • Canada

        #4
        Re: RCA LED46C45RQ backlight but no picture

        At this point we don't know if video is actually coming from the main board or not. If there is something coming from the main board, then check the TCon, etc... The LVDS cable itself being bad? Not really. So buying a board at this stage is not so hot, since you don't know which one to buy, unless you just throw money at it and cross fingers that it will fix it.
        The are some TVs that have trouble with the eeprom going bad. By freezing it and turning the TV on I'll give it a 75% chance to turn on, if that is the problem.

        Comment

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