Troubleshooting LCD inverters: what makes them fail?

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  • jpm
    New Member
    • Aug 2009
    • 3

    #1

    Troubleshooting LCD inverters: what makes them fail?

    My Dell D610 Display started to go bad - it was purplish when starting up, then one day it blacked out. I was able to revive the display for a while by pressing the lid-close switch, but then finally it became unusable.

    I removed the inverter and tested it in an older D600 display and it worked fine. I pulled the D600 inverter and put it in the D610, and my display is usable, but something is still wrong with it. There's a very high pitched sound coming from the inverter. I also still get the purple tinge for a couple of seconds when it first turns on.

    So I'm suspecting that the inverter isn't the root cause, and that if I leave things as they are, I'm going to be replacing inverters every few weeks/months.

    Could the CCFLs cause this problem some how? I thought if the CCFL failed, the display wouldn't light up at all.

    If it's not the CCFL, then could the power to the inverter be the problem, or something else?
  • kc8adu
    Super Moderator
    • Nov 2003
    • 8832
    • U.S.A!

    #2
    Re: Troubleshooting LCD inverters: what makes them fail?

    bad lamp.

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    • EGuevarae
      Badcaps Legend
      • Nov 2008
      • 1336
      • USA

      #3
      Re: Troubleshooting LCD inverters: what makes them fail?

      Originally posted by jpm
      My Dell D610 Display started to go bad - it was purplish when starting up, then one day it blacked out. I was able to revive the display for a while by pressing the lid-close switch, but then finally it became unusable.

      I removed the inverter and tested it in an older D600 display and it worked fine. I pulled the D600 inverter and put it in the D610, and my display is usable, but something is still wrong with it. There's a very high pitched sound coming from the inverter. I also still get the purple tinge for a couple of seconds when it first turns on.

      So I'm suspecting that the inverter isn't the root cause, and that if I leave things as they are, I'm going to be replacing inverters every few weeks/months.

      Could the CCFLs cause this problem some how? I thought if the CCFL failed, the display wouldn't light up at all.

      If it's not the CCFL, then could the power to the inverter be the problem, or something else?
      Purple/Pink hue is a sign of a lamp in its final hours. Pitched sound can be voltage arcing from a broken end of the lamp, or an inverter saying that it is being overloaded by a faulty CCFL. Change the CCFL as KC suggested.
      There are 10 kind of people in this world: those that understand binary, and those who don't.
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