TC-40A420U

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  • natron734
    New Member
    • Mar 2017
    • 2
    • USA

    #1

    TC-40A420U

    Hey all,

    I have this TV that's ideal. It's a Panasonic TC-40A420U. What I love about it is that it's 42" and perfect size for a spot on the wall. And it's NOT a "SmartTV". I just want it to take a signal and show it to me.

    My problem: (and for those who don't want to gag on TLDR stuff...)
    I turn it on and the screen displays for a sec, and then shuts off. Power LED flashes repeatedly. Yes, there's a pattern. Yes, I've found some related service info from "sibling/cousin" models MFG'd around that time. No, the info has not led me to the root cause which I suspect is a board SMD component, resistor, trace, or other. I have two power boards, and two signal boards. TNPA6029 (pwr) and TNP4G565 3 A (Main/signal board)

    just wondering if anyone has, or has access to any deeper info than what a moderate deep dive internet search can provide.

    I am able. I have multimeter, microscope and o-scope access.

    Just looking for info or advice

    THANKS IN ADVANCE - and I mean that. I appreciate, I know what it's like.

    Have a great day!
  • nomoresonys
    Badcaps Legend
    • Jan 2013
    • 12196
    • U.S.

    #2
    You have about a 2014 model, likely bad backlights, get yourself a backlight tester if you don't have one, they are very useful. You will get more accurate help with good focused straight on pictures. One of each board and one of the whole back as to see how everything is connected.

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