Lg 32le4900 no video,sound and backlights

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  • mattd_robinson
    New Member
    • Nov 2020
    • 8
    • United Kingdom
    #21
    Re: Lg 32le4900 no video,sound and backlights

    Yes, 923 ohms with the positive test lead on collector and the other one on emitter. I get nothing if I test the other way round. Q8003 base is indeed reading as 0V. What do you reckon?

      Comment

      • dick_barton
        Badcaps Legend
        • Aug 2015
        • 6643
        • Wales
        #22
        Re: Lg 32le4900 no video,sound and backlights

        At this point I would be suspecting Q8001 as faulty. 0v on the base should give 12V on its collector. This would switch on Q8003 which results in dropping the voltage at the gate of the mosfet Q8004 down towards approximately 1.8V.

        Also the reistance you measured is very low.
        Willing to help but I'm no expert.

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