No announcement yet.

Help diagnosing broken LCD

  • Filter
  • Time
  • Show
Clear All
new posts

  • Help diagnosing broken LCD

    Anyone willing to help me figure out what is wrong with my LCD? The backlight doesn't come on and there is no voltage out of the step-up transformer. I could probably get most of the circuit drawn up, and do some test points, but I don't know exactly what everything does. I haven't taken those classes yet. It would be much appreciated.

  • #2
    C'mon people I need a savior here! I'm sure you all know the urgency when doing without your mp3 player and GPS.


    • #3
      u need to tell us what kind of LCD is it, where r u drawing power from things like that. i am sure once we have the info to determine the problem we will attemp to provide a solution


      • #4
        Ok well it is a sharp screen with some other electronics. The deal is a capacitor within the power supply circuit for the backlight blew. I replaced it. There is no voltage coming out of the step-up transformer to the backlight. I assume the screen is fine but the backlight is not. I would like someone to tell me how to test this transformer, which has 5 inputs and 4 outputs, I assume because the level of brightness of the backlight is variable. There are switching elements that control how many of these are connected to voltage. The transformer is glued with hot glue to the PCB. That's all I will say now. If you know someone that can help me with this or if you can, please let me know.


        • #5
          Have you checked all fuses, fuesable resistors, etc? When capacitors blow, there is usually other damage...

          Aaron Cake
          London, Ontario, Canada

          Player: Cyrix 200, 32MB RAM, 10.2Gig Quantum HD, Onboard EtherNet/Sound/Video, Custom Lexan Case, Arise DC-DC, Win95 Kernal w/Custom Player
          Car: '86 Mazda RX-7 w/Basic Performance Upgrades
          Player: Pentium 166MMX, Amptron 598LMR MB w/onboard Sound, Video, LAN, 10.2 Gig Fujitsu Laptop HD, Arise 865 DC-DC Converter, Lexan Case, Custom Software w/Voice Interface, MS Access Based Playlists
          Car: 1986 Mazda RX-7 Turbo (highly modded), 1978 RX-7 Beater (Dead, parting out), 2001 Honda Insight
          "If one more body-kitted, cut-spring-lowered, farty-exhausted Civic revs on me at an intersection, I swear I'm going to get out of my car and cram their ridiculous double-decker aluminium wing firmly up their rump."