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Need help fixing a vizio sv421xvt

  1. Aug 8, 2012 #1
    The vizio logo lights up yellow but the tv screen stays black. I opened it up the on board fuse seems fine and none of the caps are blown on it. The neighbors house was hit by lighting. The tv worked before the storm but not after.
  2. jcsd
  3. Aug 8, 2012 #2
  4. Aug 8, 2012 #3
    Could it be fixed?
    without replacing the board?
  5. Aug 8, 2012 #4
    To be slightly technical, the reason it is currently not turning on is due to the powersupply not telling the main board to turn on, or the main board ignoring the powersupply.

    This might sound quite strange but its a definite way to tell, any burnt plastic smell from inside means something has been fried, if its the power supply that smells horrific replace that (unlikely due to the yellow light coming on) if there is a part on the main board that smells horrible you may just need to get that part fixed.

    Most likely its where the power supply connects to the main board.

    sorry that im not of much help.
  6. Aug 8, 2012 #5
    r4z0r84 is there any picture that you can show me so that i know what i'm looking for?
  7. Aug 8, 2012 #6
    Do you think because the neighbor got struck that the tv stopped working?
  8. Aug 8, 2012 #7
    Yes i believe the lightning strike has effected your TV, first off i would turn off your TV have it unplugged for a good hour try to turn it on a few times while its not plugged in.

    this sometimes fixes problems where the capacitors are over charged due to power surges (only going off this as it fixed a few problems i had with an old computer)

    In terms of where to look on the inside, around the top right where the power button is located, and in the lower middle left where the power cable is plugged in, i lost my computer to an electrical storm once, as i did not have any surge protectors it went straight to my pc and ~BANG~ it was destroyed, sounds quite similar to what has happened with your TV minus the BANG as your power supply sounds to be working (yellow light works) i had to replace my power supply and my PC was fine, my pc would not turn on much like your tv, although yours is getting power so it would mean the board has been fried. but yeah try to just unplug it as stated above see how you go it may or may not work but it surely cant do any more damage.

    If there is no visual damage or distinct burnt plastic smell, it may just be the end of the main boards life only saying this due to others having the same problem but without any power surges, in hind sight no one should run any type of electrical equipment without surge protectors. as lightning can destroy close to anything electronic due to the extremely high voltage.
  9. Aug 8, 2012 #8
    i wish there was a way to capture lightning to power homes :(
  10. Aug 8, 2012 #9
    Creating something that can withstand a lightning bolt, and harness its energy reminds me of Telsa, AC batteries would need to exist before we could harness any of that energy sadly but i do agree and wish the same. :cry:
  11. Aug 9, 2012 #10
    Interesting ac battery is this because lightning is ac?
  12. Aug 10, 2012 #11
    Yup, and you cant store AC power haha
  13. Aug 10, 2012 #12
    well that sucks :(
  14. Aug 10, 2012 #13
    Most all damage has no visual indication. Nobody can make an honest suggestion without first defining what the incoming and the other outgoing electrical path was. Once you know that, then anyone can also say why you have that electrical spike inside the house. You had damage because the electrical spike was permitted inside. And because it found an excellent path to earth, destructively via your TV.

    A lightning strike far down the street is a direct strike incoming to all your appliances and all your neighbor's appliances. Are all damaged? No. Once inside, it went hunting for the best path to earth. In your case, the TV.

    Often, a damaged part is the outgoing path. Others use assumption to 'know' that damage was the incoming path.

    Cable and telephone wires are required to already have best protection. AC electric only has protection if you properly earthed a 'whole house' protector. So a likely damage path was incoming via AC. Outgoing on parts most likely damaged (HDMI port, coax cable connection, etc).

    Lightning is a microsecond event. High power and low energy. If anything can store that energy, then the same item would block or absorb surges. Nothing can block or absorb that microsecond current. Which also says why protectors too close to appliances also do not claim to protect from that type of surge.

    AC batteries are easily created. Simply a DC battery and bridge rectifier. Same concepts also convert AC mains to DC voltages. And convert AM radio signals to audio signals. But no battery can absorb energy in microseconds.
  15. Aug 10, 2012 #14
    Thanks Weston is it worth fixing it or selling it for parts?
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