Philips 32PFL3008H/12 bad backlight

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  • d4vidb
    New Member
    • May 2018
    • 2
    • Slovenia
    #1

    Philips 32PFL3008H/12 bad backlight

    Hello, I'm repairing Philips TV which has Vestel 17IPS19-5p power supply. So far I replaced 400V MOSFET, diodes and MP3394 and TV started to work again but with very low brightness and I only see the picture in the dark room.
    Voltage across the LED is around 50V which is not enough I guess?
    What should I check? Capacitors are OK, so I don't know what else to check.
    Tags: None
    • ngth82
      Badcaps Veteran
      • Jul 2015
      • 541
      • USA
      #2
      Re: Philips 32PFL3008H/12 bad backlight

      Please post clear pics of the boards.

      What happens if you test the backlights with a backlight tester?
      What is the voltage output of the LED driver pins?

      I ask because i've seen LED strips that appear much dimmer compared to the strip next to it. Some of the LEDs have probably gone bad and requires a lot more current to get them to full brightness. Time to replace the LEDs or get a new panel strip.

      -Thomas
      -Thomas
      I'm a hardware engineer focused on networking equipment for my day job. I void warranties and fix consumer electronics for fun.

        Comment

        • snowfun
          Member
          • Aug 2012
          • 21
          • Portugal
          #3
          Re: Philips 32PFL3008H/12 bad backlight

          hi,
          I have a silimar case and my fault was ic driver MP3394, the voltage was low and image very dark.
          You need make a test with the led bars first 50v is low (for example: in 32" tv backlight have 2 bars with 11 leds , well 11x3v =33 x2 = 66v



          Regards.

            Comment

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