Coby LEDTV5028 sound no picture

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  • jstiene
    Senior Member
    • Feb 2013
    • 148
    • USA

    #1

    Coby LEDTV5028 sound no picture

    Hello.

    I have a Coby LEDTV50278 50" LED TV. When I turn it on, the backlight and picture (HDMI input video menu) appears for one second on the screen and then the backlight goes out. Sound works fine. I picked this up as a new TV returned, so it was basically never in service (out of warranty). I noticed this TV has an LED Driver board. Is that where I should start? I was wondering if anyone has done any repairs on this particular model.

    Thanks for any help in advance..
    joe
  • budm
    Badcaps Legend
    • Feb 2010
    • 40746
    • USA

    #2
    Re: Coby LEDTV5028 sound no picture

    You need to find out if the main board is sending the BL_ON signal to turn on the backlights or not first, and then some voltage testing on the connectors.
    Also:
    https://www.badcaps.net/forum/showthread.php?t=39740
    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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