Westinghouse DW39F1Y1 no backlight

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  • PeteTait
    Newer Member
    • Jan 2014
    • 41
    • United States
    #1

    Westinghouse DW39F1Y1 no backlight

    So i read some of the other Threads for this TV and tried to follow. I attached 2 pictures if i need more i can get them. I have no Backlight. I Tested the Female connector to the LEDs and nothing was shorting to ground. I Tested Voltage on the connector on the PWS board and had the 26-28 volts standby and Here is what i found different that i havent heard anyone say anything about. When i powered it on to test voltage i got the 80v right away but then it steadily started going down the longer it was on. What do i look for next?
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    • dskall
      Badcaps Legend
      • Oct 2016
      • 2905
      • usa
      #2
      Re: Westinghouse DW39F1Y1 no backlight

      Well for me if it has an image on the screen and no backlights I go straight to bad leds. But I guess it's best to go through all the tests first
      I assume no responsibility for any stupid suggestions I might post.

        Comment

        • PeteTait
          Newer Member
          • Jan 2014
          • 41
          • United States
          #3
          Re: Westinghouse DW39F1Y1 no backlight

          Should i have a constant voltage from the connector on the PWS board for the LEDs? Not one that is decreasing? i just wondering if i need to look at something other then the LED's

            Comment

            • budm
              Badcaps Legend
              • Feb 2010
              • 40746
              • USA
              #4
              Re: Westinghouse DW39F1Y1 no backlight

              28VDC at stansdby is the input Voltage feeding the Voltage Boost converter that boost the Voltage up to higher Voltage drive the LED string, you only has one LED string in this TV.
              If there is no load due to open circuit in the LED string the output Voltage will go up pass the safety trip point then it will shutdown so all you will see at the LED connector is the input Voltage which is the 28VDC.
              It will help to pin point the problem if you have the LED tester to test the LED string.
              At this point it looks like you have open circuit in the LED STRING, according to shopjimmy, it uses 3 LED strips.

              http://www.shopjimmy.com/catalogsear...house+DW39F1Y1
              Last edited by budm; 06-26-2017, 09:46 AM.
              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

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