50H5G no backlight

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  • SHADOW3277
    Senior Member
    • Jun 2014
    • 123
    • United States
    #1

    50H5G no backlight

    Have a Hisense 50H5G no backlight. Can see a picture with a flashlight.
    I have 2v on the red wire and 0 volt on the white wire going to the LEDs.

    PWM2 is 3.2v and SW is 2.8. IS SW BL_ON and is that voltage high enough?

    From the top down
    19v (16v)
    19v (16v)
    0v (GRD)
    3.7v (STBY?)
    12v (12v)
    12v (12V
    2.8v SW
    3.2v PWM2
    0v (GRD)
    0v GRD)



    Main filter caps on PS is 380v
    Attached Files
    Last edited by SHADOW3277; 11-06-2017, 11:16 AM.
    Tags: None
    • Andrew F. Ali
      Badcaps Legend
      • Jan 2014
      • 2450
      • Trinidad & Tobago
      #2
      Re: 50H5G no backlight

      What brand of TV is this...LG perhaps??....Any way it would seem you have failed backlights.

        Comment

        • SHADOW3277
          Senior Member
          • Jun 2014
          • 123
          • United States
          #3
          Re: 50H5G no backlight

          Sorry. It's a hisense. I thought it was the LED's before I opened it but there are no voltages to the LEDs from the PS.

            Comment

            • Andrew F. Ali
              Badcaps Legend
              • Jan 2014
              • 2450
              • Trinidad & Tobago
              #4
              Re: 50H5G no backlight

              Put the BLACK lead of your DMM on the chassis (GND) and the RED lead on the V+ on the backlight jack. Turn on TV and see if the voltage goes HI 9190Vdc) and then drop LO (2.0Vdc).

                Comment

                • SHADOW3277
                  Senior Member
                  • Jun 2014
                  • 123
                  • United States
                  #5
                  Re: 50H5G no backlight

                  It starts out at 0 when turned on it goes up to 2v and no higher

                    Comment

                    • budm
                      Badcaps Legend
                      • Feb 2010
                      • 40746
                      • USA
                      #6
                      Re: 50H5G no backlight

                      We need good clear straight shot pictures of the whole backside of the TV showing all the boards and then straight shot pictures of the top and bottom side of the power supply board.
                      Never stop learning
                      Basic LCD TV and Monitor troubleshooting guides.
                      http://www.badcaps.net/forum/showthr...956#post305956

                      Voltage Regulator (LDO) testing:
                      http://www.badcaps.net/forum/showthr...999#post300999

                      Inverter testing using old CFL:
                      http://www.badcaps.net/forum/showthr...er+testing+cfl

                      Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                      http://s807.photobucket.com/user/budm/library/

                      TV Factory reset codes listing:
                      http://www.badcaps.net/forum/showthread.php?t=24809

                        Comment

                        • SHADOW3277
                          Senior Member
                          • Jun 2014
                          • 123
                          • United States
                          #7
                          Re: 50H5G no backlight

                          Here are the other pics.

                          Here is the PS at SJ. http://www.shopjimmy.com/hisense-171...upply-unit.htm
                          Attached Files
                          Last edited by SHADOW3277; 11-07-2017, 06:43 AM.

                            Comment

                            • SHADOW3277
                              Senior Member
                              • Jun 2014
                              • 123
                              • United States
                              #8
                              Re: 50H5G no backlight

                              Bump. Purchased a used PS and I am still only getting 2 volts off the PS to the LED's.

                                Comment

                                • Andrew F. Ali
                                  Badcaps Legend
                                  • Jan 2014
                                  • 2450
                                  • Trinidad & Tobago
                                  #9
                                  Re: 50H5G no backlight

                                  I already told you that you have failed backlights.....

                                    Comment

                                    • SHADOW3277
                                      Senior Member
                                      • Jun 2014
                                      • 123
                                      • United States
                                      #10
                                      Re: 50H5G no backlight

                                      Originally posted by Andrew F. Ali
                                      I already told you that you have failed backlights.....
                                      You said bad LEDs.

                                      I said I didn't have voltage to the LEDs from the PS.
                                      You said to check again to see if the voltage jumped when turned on.

                                      I said it didn't.

                                      Then I heard nothing else.

                                      Even with bad LEDs shouldn't there be voltage from the PS to the LEDs?

                                        Comment

                                        • vinceroger69
                                          Badcaps Legend
                                          • Mar 2012
                                          • 6714
                                          • uk
                                          #11
                                          Re: 50H5G no backlight

                                          maybe worth watching
                                          https://www.youtube.com/watch?v=Cnr5NdxV5gU

                                            Comment

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