JVC LT-40C550 PSU Backlight Fault

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  • jdawg99
    Member
    • Sep 2022
    • 11
    • United Kingdom
    #1

    JVC LT-40C550 PSU Backlight Fault

    Hi Guys,
    Wonder if I can get some advice on this please. The fault is a noticeable darker screen on one half of the TV. I have checked both arrays and they seem fine. I have swapped the led outputs on the PSU and proven it's not the LED's. There is a bad output voltage on one of the ports but seems almost like some kind of grounding issue or something. From TV chassis I get 60+ Volts on the positive of each string but if I measure across the bad one (tested on both arrays) I only get 2 ish volts. If I measure from TV chassis ground to the negative I get 32v. I have done a little video to show what I mean

    https://www.dropbox.com/s/gz4yisxm48...10011.mp4?dl=0


    The PSU is a TV3902-ZC02-01(F)) and the IC I am measuring on is a ob3368ap.

    Thanks in advance
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