RCA LED55C55R120Q no backlights

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

    RCA LED55C55R120Q no backlights

    I have an RCA LED55C55R120Q that I picked up from my local recycling center. It was in the original box and is in really good condition. It turns on with no backlights. This is what I have tested so far:

    I can see an image on screen with a flashlight.

    I get 3.3 at bl_on and adj pin and it stays steady.

    At LED + pins I get 132v when I turn the TV on but that quickly drops, eventually reaching less than a volt.

    I am guessing I probably have bad LED's but wanted to be sure.
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    • Moreno83
      Badcaps Legend
      • Jun 2014
      • 2008
      • The Netherlands
      #2
      Re: RCA LED55C55R120Q no backlights

      I think i need to move to the states , all people bring their broken tv's to the recycling center/dump haha.

      It probably has a bad led that pulls the voltage down. Tv turns on so good chance that the psu is good.
      I only repair Panasonic plasma tv's! Currently owning a TX-P55VT50 and still searching for a ZT60!

        Comment

        • SLK001
          Badcaps Veteran
          • May 2014
          • 264
          • USA
          #3
          Re: RCA LED55C55R120Q no backlights

          Yes, it is a bad LED or two. IIRC, the white background in the LED "chamber" is stuck down with double-sided tape. Use a hairdryer to soften the glue while you remove it to get to the strips.

            Comment

            • SHADOW3277
              Senior Member
              • Jun 2014
              • 123
              • United States
              #4
              Re: RCA LED55C55R120Q no backlights

              Thanks for the confirmation on the LEDs.

              Moreno83 - You wouldn't believe what I find at my electronics recycling center. I picked up a 50" Toshiba Smart TV a few weeks ago that just had a bad cap. Popped in a new one and it has worked perfectly since.

                Comment

                • vinceroger69
                  Badcaps Legend
                  • Mar 2012
                  • 6714
                  • uk
                  #5
                  Re: RCA LED55C55R120Q no backlights

                  i wish we had electronics recycling center s in the uk i could get some project sets to work on then do you have to pay the recyclying centers in the us

                    Comment

                    • budm
                      Badcaps Legend
                      • Feb 2010
                      • 40746
                      • USA
                      #6
                      Re: RCA LED55C55R120Q no backlights

                      Originally posted by SHADOW3277
                      Thanks for the confirmation on the LEDs.

                      Moreno83 - You wouldn't believe what I find at my electronics recycling center. I picked up a 50" Toshiba Smart TV a few weeks ago that just had a bad cap. Popped in a new one and it has worked perfectly since.
                      Do you have to pay for the TVs?
                      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

                        • Malachi
                          Badcaps Legend
                          • Dec 2015
                          • 1077
                          • Usa
                          #7
                          Re: RCA LED55C55R120Q no backlights

                          I've looked for electronics recycling places near me and I can't find any.

                            Comment

                            • SHADOW3277
                              Senior Member
                              • Jun 2014
                              • 123
                              • United States
                              #8
                              Re: RCA LED55C55R120Q no backlights

                              I usually pay around $5 per tv. If I have to take the tv back, say its too expensive to fix or cant get the part, ill strip the good parts and then pay another $5 to drop the tv back off.

                                Comment

                                • Malachi
                                  Badcaps Legend
                                  • Dec 2015
                                  • 1077
                                  • Usa
                                  #9
                                  Re: RCA LED55C55R120Q no backlights

                                  Do these places have a name? I've tried to google electronic recycling centers but not really finding anything.

                                    Comment

                                    • SHADOW3277
                                      Senior Member
                                      • Jun 2014
                                      • 123
                                      • United States
                                      #10
                                      Re: RCA LED55C55R120Q no backlights

                                      I have several recycling centers in my area, most didnt take electronics. I found one that did and just asked the guy in charge if if I could buy stuff from them.

                                        Comment

                                        • allsmith
                                          Senior Member
                                          • Aug 2012
                                          • 179
                                          • United States
                                          #11
                                          Re: RCA LED55C55R120Q no backlights

                                          I go to a transfer station,and have found quite a few...actually just brought home a 46'' sanyo led today...busted screen of course but be good for experience...Maybe harvest the led's for a project

                                            Comment

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