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screen too dark after power supply replacement

after replacing the power supply in my vizio tv, everything works, but the screen is too dark... and theres a faint crackling noise that i think is coming from both backlights

im assuming ive plugged something in backwards, or perhaps the new power supply i got was bad?

im not sure where to turn now

i cant find the model number but the serial number is:


thanks in advance for any answers

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@lorielavender why did you have to replace the power supply to begin with? what happened to your TV? what have you checked thus far?


i pulled the tv out of a snow bank a couple years ago, someone had thrown it away cause one of the back lights didnt work... so i replaced the board that runs it and it worked fine for a few months... then the power supply died (nothing worked but the vizio logo)... so i got a new one of those (maybe it was used) and that got me to where i am now... picture too dark and a faint crackling sound coming from the back lights

i thought the problem was that i had reversed the plugs to the backlights... but i tried switching them and i get the same results


thanks for the schematic

it seems everything is plugged in right...

i had to reset the settings (options menu) to get the backlight adjuster to come up in the picture menu... very strange... but now that its there, adjusting it doesnt seem to do anything

about the only thing i can think is it must be a bad power supply, not sending enough power to the backlight inverters


Sounds like your power board is not doing something right. Take a look at the MOSFETS and the transformer. See if you may have a corroded or loose solder joint. The concern I have is that you get the "crackling sound coming " at the backlights. Since it is a LED backlight there should be no sound even if there are power issues.


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@lorielavender could very well be a bad or incorrect part. See if the attached image will help to verify that you connected things right. This shows the disassembly so things will be in opposite order for the reassembly

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lorie will be eternally grateful.
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