UN46EH6000 does not turn on and no LED

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  • R_J
    Badcaps Legend
    • Jun 2012
    • 9514
    • Canada

    #21
    Re: UN46EH6000 does not turn on and no LED

    in a word, Yes. transformers do not pass dc, it gets switched at a high frequency around 100khz

    Comment

    • Plane Nuts
      Senior Member
      • May 2019
      • 52
      • Canada

      #22
      Re: UN46EH6000 does not turn on and no LED

      Getting ready to order the part, and the main fuse, should I be getting slow blow or fast acting? I don't have access to the fuse to see the actual number on it.

      Comment

      • R_J
        Badcaps Legend
        • Jun 2012
        • 9514
        • Canada

        #23
        Re: UN46EH6000 does not turn on and no LED

        What's marked on the board? is it T6.3AH/250v That is a slow blow (or time delay) fuse, a fast blow likely would not last.

        Comment

        • Plane Nuts
          Senior Member
          • May 2019
          • 52
          • Canada

          #24
          Re: UN46EH6000 does not turn on and no LED

          It has been a while but finaly got around to replacing the ICM801 as suggested in previous posts, and I am back to square one, TV does not turn on. here is the new status:
          Red LED light flashes once every 7 seconds

          1 B13V Tested 0.4v
          2 PWM_DIM Tested 0v
          3 B13V Tested 0.4v
          4 B13V Tested 0.4v
          5 Vamp Tested 0.4v
          6 BLU_on/Off Tested 0v
          7 Vamp Tested 0v
          8 GND
          9 GND
          10 GND
          11 B5V Tested 0v
          12 A5V Tested 5.2v
          13 B5V tested 0V
          14 Power on/Off Tested 3.2V

          Here is what I get at ICM801 between (-) of rectifier BD801S and the pin:
          1 (VDl) 394v
          2 (AR) 1.7v
          3 (RT) 1.7v
          4 (CS) .01v
          5 (SG) .005v
          6 (PG) .004v
          7 (Lvcc)14v
          9 (Hvcc) 220v (meter is all over in AC and DC mode)
          10 (Vctr) 220v (meter is all over in AC and DC mode)
          Also note it gets burning hot!!

          at TM801S on cold side I get the following(pins top to bottom as in picture on back side):
          4? 5.4v
          7? 0v
          5? 0v
          3? 5.6v
          8? 0v
          9? 0v
          also continuity between 3&4, 5&8, 9&7

          At Vdrv (exiting DM852) I get 12V

          After all of this not sure which direction to go,

          Comment

          • Plane Nuts
            Senior Member
            • May 2019
            • 52
            • Canada

            #25
            Re: UN46EH6000 does not turn on and no LED

            bumping up this thread to try to get to the bottom of my issue.

            Still trying to find out why I am not getting the B5V and B13V. Looking at the schematic I believe the B13V is what will activate the FET QM854, to let A5V through to become B5V.
            so chasing the 13V I get 0V at TM 801 pin 9 and 5 even though the other side of the individual coils I get 5.4 V at pins 8 and 7. disconnecting the common leg on DM855/855 there is no change.

            where does Vdrv go to?

            testing FET QM854 I get the following
            S to D in res mode .3 Meg and in diode mode .4 ohm
            and reversing leads:
            D to S in res mode 1.7 Meg and Open in diode mode

            S-G in res mode 86K in both directiions
            S-G in diode mode .6 one way and open the other.

            I hope with this info I can find a direction

            Comment

            • Plane Nuts
              Senior Member
              • May 2019
              • 52
              • Canada

              #26
              Re: UN46EH6000 does not turn on and no LED

              To Follow up, I have found the issue as to why I was not getting the needed voltages, and unfortunately it was self induced, when I removed the capacitors to test them, CM813 got misplaced and was not re-installed so the coil was not being powered properly

              Comment

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