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Haier Inverter board PSU/CCFL question...

Hello,

I'm in the process of repairing a Haier L30CV6 flat panel TV. I thought there was a problem with the inverter board, as the unit remains powered on but the CCFL tubes only flash on for a second, then remain off. However, having replaced the inverter with a known working one, I still have the original problem.

Can anyone tell me if all the CCFL tubes light if only briefly, then can I presume none are faulty? Also, should the 24v rail be 24v, as it's currently reading 25.3v?

Any suggestions much appreciated please :-)

Thank you,

Ian - UK

Posted by on

  • iansmusical
    iansmusical Jan 12, 2009

    Hi Daniel,

    Many thanks for your help. Can I query if you're sure one of the CCFL tubes has died, on the grounds that overvoltage protection on the OZ960 IC (inverter board) is not active?

    Thank you, appreciated.

    Ian - UK


  • iwilson7
    iwilson7 Mar 08, 2014

    I had a TV that lit the CCFLs for just a second or so and then go dark after powering on. It was one bad CCFL. Blew up (lightning strike?) a bulb. Replaced one bulb never went dim again. First LCD TV I ever "fixed".

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Change the lamps unit will work fine.
regards,
daniel

Posted on Jan 12, 2009

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