General - Backlight LEDs Q.

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  • stav242
    Senior Member
    • Jan 2014
    • 61
    • United Kingdom
    #1

    General - Backlight LEDs Q.

    I have a single faulty LED on a backlight strip of this Technika 32" 32F21B-FHD TV.

    as a bit of a trial, i thought i would try stacking a salvaged LEDs cut out from other scrap TVs - but it seems the LED brightness and colour vary on the others... and with the diffuser back on its quite noticable that the new LED is not the same as the others, too bright or blue tint.

    is there any info out there on what SMD LED types are used on specific models - or how to identify the SMD LED part code easily. ?

    in the long run, i would rather replace the SMD LED on the strip for 50p than have to fork out £20 a time for a complete new strip. - often more than the 32" Tv is worth.
    i replaced one as a test, fiddly, but possible.

    i found this post but only discusses the size related to the product number (which is helpfull)
    https://www.badcaps.net/forum/showth...hlight=SMD+LED

    - alternatively, the SMD LED rolls of 100 are about £6 - i could always buy a few different types and try my luck...
    Last edited by stav242; 01-05-2022, 03:54 AM.
    Tags: None
    • diif
      Badcaps Legend
      • Feb 2014
      • 6978
      • England
      #2
      Re: General - Backlight LEDs Q.

      Trial and error or a spectrometer. Whilst it is cheaper to replace single LEDS, all of them will have the same life, if you're selling these with warranty, there is a very good chance they will return.

        Comment

        • ducky29
          Badcaps Veteran
          • Dec 2015
          • 370
          • Europe
          #3
          Re: General - Backlight LEDs Q.

          You will waste a lot of time and patience if you choose to remove the lens, replace led, glue back the lens. You will need at least 2-3 hours from start to finish.
          Also packages are different, there are 3528 3030 3volts, 6volts, etc etc, you might find it difficult to find the correct replacement.

          I bought this https://www.aliexpress.com/item/32474591848.html for 10$ in 2017 and I have only used about 50 on clients who would only have 1 or 2 faulty leds and would not accept the qoute for full array.If you have the same led as I listed above I can send you as much as you want as long as you pay for shipping.
          I don't think its worth your time. Based on my experience it better to replace the whole set and you are good to go for at least 2-3 years.
          But its up to you, if you have the time and skills to do it then go ahead!

            Comment

            • stav242
              Senior Member
              • Jan 2014
              • 61
              • United Kingdom
              #4
              Re: General - Backlight LEDs Q.

              im just doing it for a hobby... so happy to spend more time on it and keep the costs down.

              i found a ebay seller who quotes the SMD LED types suitable for particular manufacturers... a bit closer than guessing..

              https://www.ebay.co.uk/sch/tvrepairledtester

              eg..

              100pcs 3528 2835 3535 8520 7020 SMD Lamp Beads For LG LED TV Repair
              100Pcs 3537 3535 2828 3228 5630 7032 SMD Lamp Beads for Samsung LED TV Repair
              100Pcs 7020 SMD LED Lamp Beads 6V For Philips Skyworth LED TV Strip Repair

                Comment

                • alfatv
                  Badcaps Veteran
                  • Sep 2020
                  • 353
                  • Canada
                  #5
                  Re: General - Backlight LEDs Q.

                  Originally posted by stav242

                  as a bit of a trial, i thought i would try stacking a salvaged LEDs cut out from other scrap TVs - but it seems the LED brightness and colour vary on the others... and with the diffuser back on its quite noticable that the new LED is not the same as the others, too bright or blue tint.
                  This is doable, you need to get LED tester, then compare original and target LED for voltage, current and color.
                  Another check is for LED size and footprint.
                  Also often worn out LED's are blueish and don't match original color.

                    Comment

                    • stav242
                      Senior Member
                      • Jan 2014
                      • 61
                      • United Kingdom
                      #6
                      Re: General - Backlight LEDs Q.

                      Update.
                      Ordered some 3030 and some 3528s.

                      Tested existing led current on both the new ones compared to existing

                      and used a simple Lux metre all on my phone to guage brightness...

                      Using both current and lux, it was enough to match up a replacement 3528 led to the existing ones on the strip.

                      Much cheaper and more sustainable then replacing the while strip.

                        Comment

                        • neilc6
                          Badcaps Legend
                          • Nov 2015
                          • 1550
                          • Canada
                          #7
                          Re: General - Backlight LEDs Q.

                          LED failures aren't random. They wear and have limited life just like light bulbs. Replacing single LEDs isn't worth it since the remaining LEDs will eventually fail. I had two TVs recently come back which were repaired with used strips and the backlights turned down. One came back in about 8 months (owner couldn't wait for new strips so I replaced with used and ordered new strips for him to hold onto - LG 42LN) and second came back shy of 2 yrs (Sharp 50LB). Don't bother with RCAs any more since they have low resale value and can't get new strips.
                          Last edited by neilc6; 01-10-2022, 02:44 PM.

                            Comment

                            • jimbofz
                              Badcaps Veteran
                              • Apr 2013
                              • 537
                              • uk
                              #8
                              Re: General - Backlight LEDs Q.

                              any idea why sharp leds have 10 volts across them not 3v or 6v?
                              model LC40LE600E

                                Comment

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