T-con or Main board Fault in LED TVs

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  • Ahakim
    Member
    • Apr 2013
    • 64
    • USA

    #1

    T-con or Main board Fault in LED TVs

    I must say I'm new with LED TV repair...
    First: What's different from LCDs besides Backlighting?? What does the absence of backlight mean in most cases of LED TVs? (sound good...)
    Can someone explain how the LEDs (in the four edges of the panel) are mounted in the circuitry and powered? Are they in series? What are the voltages involved, led driver board ?
    secondly:

    Is there a way to quickly detect weather a fault in Led TVs (such as " Backlight ON but NO Picture") is in the T-con or the Main board without replacement. 50 per cent of cases encountered in LED Tv sets (at least by me) are problems with above symptoms!
    Any repair guide for this type of TVs??
    Thanks.
    Last edited by Ahakim; 11-09-2015, 04:21 PM.
  • ReeceyBurger123
    Never Give Up !
    • May 2014
    • 7325
    • Britain

    #2
    Re: T-con or Main board Fault in LED TVs

    The only difference between conventional Lcds and Led tvs is the backlight.

    Most common cause of sound no picture on Led tvs is failed Led bulbs however I have seen failed drivers cause no backlight.

    Edge lit Leds will all be different on where the Led strips are located some on the top, some on the bottom, some have 1 set of Leds some have 4.

    Leds in Tvs are wired in series like christmas lights, so one out all out !

    Each Led uses about 3v 10ma in tvs so when they are all in series depending on the ammount of Leds a few hundred volts will be going through them and each Led will drop its respective voltage.

    The Led driver creates the high voltage for the Leds.
    Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

    https://www.facebook.com/Telford-Tel...7894576335359/

    Comment

    • ReeceyBurger123
      Never Give Up !
      • May 2014
      • 7325
      • Britain

      #3
      Re: T-con or Main board Fault in LED TVs

      I will try and find a thread which shows how to test a Tcon and Mainboard. Also very common issues on Led Lcd tvs with backlight no picture is the actual Lcd screens failing which is unfixable but thats not conclusive you will need to diagnose before hand to be sure.
      Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

      https://www.facebook.com/Telford-Tel...7894576335359/

      Comment

      • mattstolte
        Badcaps Veteran
        • Dec 2013
        • 612
        • usa

        #4
        Re: T-con or Main board Fault in LED TVs

        Interested in this above thread as well

        Comment

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